If you have purchased parts from Jim Carter Truck Parts to restore your truck, we are ready to accept your photos and narrative about your restoration. Please click here to submit your photos along with your story about your truck restoration and or repair project. Sorry, we can only take on 12 per year for Featured Truck of the Month.
With the introduction of the new 1955 GMC Blue Chip trucks. (Chevrolet used the name “Task Force.”) The GMC Truck Division made their statement with changes that were different in many ways than their Chevy competitor. Much of the sheet metal was identical to Chevrolet but there was just enough changes that allowed them to be a market and stand alone!
The new 1955 GMC trucks sometimes had their own independent dealers but more often their pickup line was marketed by GM car dealers such as Pontiac or Buick.
The stepside pickup beds were almost identical to Chevrolet but the tailgate displayed the famous GMC logo. (A nice advertising touch to show the follower, the pickup in front was a pure GMC.) To standout even more, the hood, grill, hubcaps and dash were much different than Chevrolet. The seat springs and frame were the same but the appearance of the cloth and vinyl gave a different appearance. Even the 6 cylinder and V-8 engines were different than Chevy! The GMC Truck Division would say “Our pickups are certainly a step above the competition.”
Through the transmissions, differentials, and brake systems were mostly the same as the Chevrolet, their engines were very different. It appears that GMC would not share this most important part from their competition.
The 1955 six cylinder was 270 cubic inch. This was the same engine that had been optional in their first series 1955 trucks. (One of GMC’s greatest in the engine category.)
In regards to a V-8 engine it appears GMC was not prepared when they discovered Chevrolet had developed a small V-8 engine. (Yes, GM had a V-8 but it was 2 very large unit used in off road equipment and commercial highway vehicles. Too large for ½ to 2 ton trucks.)
Now what? GMC did what they had done in 1938 with a similar situation. The borrowed Pontiac’s engine! They could now boast, they had the largest V-8 in a pickup truck.
Just in case, you have an interest in the Advance Design original brake system, this might catch your attention.
For ½ and ¾ tons, in the left corner of the cab floor, is the foot operated park brake. Here, the lever extends vertically up through the floor so the driver’s foot can lock the rear brakes when keeping the truck in a stopped position.
To prevent outside air from entering the cab GM used a rectangle boot cover preventing any leaks. To secure the boot, a metal plate with a long center slot attaches to the floor. The attached photo shows this as GM installed it.
A different metal plate is required when there is no foot brake. On 1 through 2 ton trucks the total hole is covered with the same plate but no center hole. Interesting! It actually then becomes a just blank-out plate to cover the now unused hole.
One of our good customers, Scott Phaneuf of Hatfield, MA recently purchased a NOS (New Old Stock) GM tool bag with all the correct tools. It was found in a San Diego dealership back storeroom. Somehow it had not been thrown away over these many years.
In earlier years canvas tool bags were with the vehicle when new at no extra charge. Later they became an extra cost option and this design is our feature item. As the quality of clear vinyl improved, they could now use this material as part of the tool bags.
Photos show the pouch, the enclosed tools, and the original cardboard box that kept the total package. The part number 987322 was for customers that had bought most all General Motors cars and trucks between 1957 through 1962.
To keep General Motors truck costs down, Chevrolet and GMC ½ through 2 ton shared many components during the late 1930’s through the 1950’s. However, when it came to the grille, the focal point of the truck, changes had to be very noticeable.
The truck designers were limited in creating a new grille as both makes would still have the same front fenders and hood. For these limitations, the designers actually did quite well. They almost made them able to be exchanged from one make to another. On the 1941-46, only the small filler panel between the grille and fender top had to be slightly modified.
The attached photos show how two grilles can be different and yet fit in almost identical sheet metal areas of the trucks.
This 1940 GMC 1 ½ ton had been retired along with its original owner, a farmer near Grand Rapids, Michigan for many, many years. It had been placed in a barn with badly damaged fenders, grille and related front items. The bed was beyond repair. If it was not for the sentimental value to family members, years later, it would have been sent to the crusher. A younger family member aware the truck was hidden in a barn began to consider updating it and making it roadworthy. The big plus was a pair of New Old Stock front fenders and running boards stored on the bed. This gave him the incentive to start on grandfather’s farm truck. It was a surface restoration but still became expensive. The bed was rebuilt at almost $900.00. Installing the new front fenders, finding a chrome grille and bumper surely added to the expense.
A second owner purchased the truck about 1993, however, he never did any further restoration. It sat for 10 years. Maybe this is the reason why it went up for sale. The big restoration money was yet to be spent.
The current owner is Mike Reese of Kempton, Pennsylvania. He bought it on-line in 2003 because he loved the appearance of the front end and cab. He became committed to make it look like new!
He already owned a 1951 Chevy fire truck and a 1951 Chevy 2 ton short wheel base dump truck (he still uses it for occasional gravel and dirt hauling) so he was very aware of what was ahead of him. However, he needed a lighter weight less massive older GM truck for driving to more distant truck shows and being more a part of the fun.
Mike did the final steps of the restoration, taking three years of evenings and weekends to complete. Total cleaning, painting the original Pimpernel Scarlet, all new rubber, correct interior, many mechanicals restored, etc. It was all done to exact 70 year old specifications. Finally, it became just like the Michigan farmer saw it when he bought the truck from the GMC dealership in 1940.
It’s now a head turner everywhere Mike takes it. People just stand and stare at the workmanship. They are looking at what they have only seen in black and white photos of the 1940’s.
After the first year of driving it on lesser traveled roads, Mike finally made one hidden change. He replaced the original 228 cubic inch six cylinder with a completely rebuilt 1956 270 engine. The outward appearance is identical. The two engines even used the same overhaul gasket set. Now the truck had a different personality. He could drive it on freeways to distant truck shows. He still keeps it about 60mph as the truck is still held back due to the original 4.56 ratio differential. He has not been able to find a higher ratio ring and pinion without making a major change that requires different wheels and he refuses to have a different design wheel on the front and rear. We offer our congratulations on this thinking.
One of the items that really stands out on this 1940 flat bed at all shows is the original GMC bed. Most display aftermarket beds, however Mike’s is pure General Motors. The two tall curved front panels (like a half barrel) are a true example of a truck that was ordered with the correct GM bed.
Mike Reese and his 1940 are often seen at Pennsylvania weekend truck shows; however his furthest was the American Truck Historical Society 2011 annual convention in South Bend, Indiana. Distance driven: 630 miles one way. This national club’s 2012 convention was in West Springfield, Massachusetts. This was 250 one way miles.
He never misses the world famous annual Macungie, Pennsylvania truck show 30 miles away. This year there were 600 participants on display. No judging, just lots of fun and memories.
Mike’s 1940 is quite an eye catcher at shows. He almost always receives a trophy or at least honorable mention. Yes, a home family room has many awards that prove this statement.
Mike Reese can be contacted by email— email@example.com
Attached are some pictures of the correct 1947-1955 GM panel truck seats. The right side was a factory option. This would be special ordered if the owner was planning on two passengers. Though they have been recovered with cloth instead of factory “leatherette”, they are correct in all other ways. What is interesting is how GM made the optional right side seat to fold up against the dash. This was necessary to allow easier access to merchandise up front. No need to unload freight to get to the front storage area. It appears the seat frame and floor is painted the original grey color. A thin sheet of insulation is placed between each of the body supports. This was to lessen road noise and slow some heat from entering the cab on hot days. Another interesting feature on panel trucks; the single horizontal oak board on each side of the interior helps prevent damage to the exterior sheet metal walls. If a stack of transported items tipped while the panel truck was making a corner, there was less chance of dents being placed on the sides. Note the long metal lid over the floor box which is under the factory optional right seat. This is only provided in the panel truck and canopy express bodies. It kept the driver’s papers in a neat compartment so they did not slide or blow across the floor.
Though things were shared between GMC and Chevrolet trucks, General Motors made sure many items remained very different during the early years. GMC preferred very few things to be similar to Chevrolet. Their customers needed to see an almost stand-alone truck with the higher price of the GMC.
One very obvious difference is the change in taillight and bracket. There is no comparison to Chevrolet. The massive GMC stamped steel one piece bracket combined with a redesigned 4 inch taillight makes the pair a “one of a kind”. They do not interchange with Chevrolet during these years.
Finding some of these parts during a total 1936-46 GMC pickup restoration has become difficult. The bracket is now produced, however, if that happens the taillight will be a big project to get. The light is not being reproduced.
Hint: This taillight was also used on Chevrolet, Buick, Oldsmobile station wagon tailgates from about 1949 through 1952. Therefore, you will see more lights than GMC brackets at swap meets.
IMPORTANT NOTICE: The 1936-46 GMC taillight brackets are now available for this 1936-46 pickup truck.
My 1955 GMC 100 was locally purchased in 1995 immediately after buying the ’62 Airstream which resided for decades in a Minnesota field. As these trucks were designed, developed, and built to be work trucks, this one would continue to be so. A few months were spent designing the Jimmy so that it could be a strong, safe, and reliable hauler to pull the Airstream, a kind of Wanderlust Hotel, anywhere in North America at anytime, weather permitting.
The Jimmy’s frame was excellent, the body mostly good, but all the external and much of the internal trim had been stripped and was gone. My other vehicles at the time were working GMC pickups as were their predecessors, but the ’55 would be a special work truck capable of safely running with the big dogs while towing. All sheet metal but the cab came off, and all electrics were replaced as was every moving and non-moving part (except the nylon odometer worm gear which just broke…who knew?).
The Blue Chip GMC pickups were low volume production and very, very few reproduction parts are available. Most of the difficult to find original replacement parts were scored from Old Chevy Trucks with Jim Carter personally pulling trim items from one of his Missouri yards (it is a rare circumstance to work directly with a company’s owner for help, not once but many times). One of the key and very tricky safety items is the telescoping side view mirrors which came from a Chevy/GMC tractor of the same generation (1955-59). These were cut down and chromed so that vehicles behind the Airstream could easily be seen while using the original door mounting holes.
The rebuild took two years before undergoing a flawless 1300 mile test drive to MN to retrieve the Airstream, another two year project. Since 1999, the GMC has averaged 13,000 miles/year, a testament to a great working truck.
At the beginning of the 1941 Chevrolet and GMC truck body style, the parking light assembly was placed on top of the headlight bucket. This was the first time both were placed on the fender as a pair. All worked well together. To save tooling costs, GM chose to add a pre-existing assembly from the year before on the 1940 Pontiac car. No changes were made from this Pontiac park light assembly except its long sheet metal top was now painted and not chromed.
Overseas during World War II, when civilian front fenders were used on GM military trucks (instead of the more famous flat fender ‘army truck’ style) General Motors created a parking light that emitted a small strip of light to be seen at a shorter distance.
Beginning in 1942 and continuing through mid 1947 (when this body design was discontinued), GM used a much less expensive park light housing on civilian trucks. A one piece stamped metal cover was attached to the headlight bucket for a fraction of the cost as in 1941. This also used a smaller less expensive glass lens.
Therefore during this 6 ½ year truck production (1941-Mid 1947) the same headlight buckets were on Chevrolet and GMC trucks. The difference was their hole punching which adapted to changes in parking light assemblies.
What a rare occurrence! At the 2011 America Truck Historical Society Convention in South Bend, Indiana, we found both a 1936 and a 1937 restored GMC truck with the correct grill — each at different booths. You can go to every truck show for many years and never see even one. Therefore, we just had to get a few photos and make some comments. After all, this may never happen again.
The 1936 grill consists of seven vertical .3′ wide hollow chrome bars all the same size. The length is 25 1/4′. The notches in the receiving die cast pieces (hold the verticals in place) in the top and bottom are the same for each bar.
By 1937-38 there was a change in the center vertical bar. It became wider. It changed from .3′ in 1936 to .625′. It was also tapered back to align with the positioning of the other side bars. The overall length was shortened to 24′.
The notches in the die cast top and bottom receiving pieces are therefore different due to the width change in the center bar. They may look the same on the outside but are not where they attach to the vertical bars. See photo. Chrome was not used to add to the appearance. These bars were painted silver.
What a unique invention. When you have a 1947 through 1959 single rear wheel 3/4 or 1 ton GM truck and need more pulling power, this is the answer. American ingenuity at its best!
This new steel center hub extension includes eight long bolts to reach the original wheel studs. This holds the factory wheel in place and then provides a threaded end for the original eight lug nuts which are holding another matching wheel.
The buyer of this aftermarket kit just had to be sure his new outer tire was the same height as the original inner tire.
Pictures and data from Scott Golding, Stratton, NE.
During the early years, most roads were not paved and the quality of tires was far from that of today. Thus, tire repair was very big business. It was necessary for vehicle manufacturers to provide the easiest access to the often needed spare tire. Part of driving a car or truck was knowing how to change a tire.
On the 1936 and older pickups, the tire storage space was limited. GM chose to place a dip in the front fender and a 29″ vertical rod from the frame rail to the cowl for the tire and wheel support clamp. A long nut is threaded to the top of the rod and tightens a curved metal over the tire. No the pickup did not use the chrome “T” handle on the car.
In viewing restored ½ ton pickups at shows it is amazing that most use the chrome die-cast “T” handle that came new on passenger cars. Not correct! The pickup uses a hexagon securing nut. It is designed to be turned by the lug nut tire tool usually stored under the seat cushion.
Why the difference is unknown. We assume the “T” handle nut is more convenience to turn. The car driver would get less dirt or grease on clothes or hands during a tire change, plus the car was usually on smoother roads, not on the rough surfaces of a farm field or back roads that might loosen the securing nut.
Replacement hard parts for most of this side mount system are not being reproduced. Originals usually must be restored. The rubber grommet that protects the cowl and fender metal from the side mount hardware the securing nut and 29″ support rod are available from Jim Carter Truck Parts along with a few other older GM truck full stocking dealers.
INTERESTING: The Chevrolet 1/2 ton (1934-1936) placed the support well in the right front fender. The 1936 GMC (first year for their 1/2 ton) it was in the left front fender. The support hardware is the same. Just another way of the two marquis showing their individuality with limited expense.
Pickup inside view. Not quite like a Chevy car.
The 29″ vertical rod is at an angle, too far through the cab mounted support. Shown is the top dark threads where this retaining nut fits.
We just couldn’t resist placing this approximately 1956 Opel as this month’s feature truck. Did you actually think General Motors discarded the famous Advance Design 1947-55 truck cab tooling? To get a little more use of the tooling, it was modified in the late 1950’s as a German Opel truck. Remember the small Opel car imported in the 1960’s and sold in Buick dealerships? They displayed the same lightning bolt emblem as the trucks.
Look closely at this pickup. It has Advance Design all over it!
Its owner is Jan van Bohemen in Germany. It started as a larger work truck, however he wanted a pickup so he made the bed and rear fenders to get the look he wanted. Very impressive!
For your information…more data on the later-use of the Advanced Design Tooling. Not only did they use this tooling in Europe but it was an assembly line produced truck in Brazil. Click here to see Brazil’s version.
When it was new, my GMC was a water truck on the Altoona PA fairgrounds. It sat under a big oak tree for many years until the second owner bought it. It didn’t have license plate on it until the 1970’s. The second owner did a basic restoration and painted it in the same colors and scheme as it was when new. He also put two speed GMC rear end in it, shortened it, and made a fifth wheel out of it. I bought it in about 1998 with 12,500 original miles, a gas ration sticker from WWII in the window and the second owner claimed the original tires which at first I didn’t believe but now I think he may be correct. My future plans are to do a more detailed restoration and install a 302 GMC engine and five speed transmission to make it more usable while keeping the original character of the truck. I will keep the tires, engine, trans and rear end so it can be returned to stock. Since I bought the truck I have only come across five of these 38 COE’s. Jim Raeder
The 1967-1972 – What’s That Noise? Gaining speed after you turn onto the highway, your GM truck (1967-1972), moves toward a cruising speed equal to the surrounding traffic. As your engine reaches about 2,000 rpm you suddenly hear a low hum up front. It does not stop as the truck speed increases. If you lower the windows, play the radio, or turn up the fan blower, this hum is not so noticeable but it is still there. How will you locate this noise source when the truck is stopped?
No problem. Others have researched this mystery noise, discovered the source, and stopped it. Who would have thought the culprit is the hood springs? It appears that on many GM trucks of this body style, the two coil hood springs develop this hum (like a tuning fork) as surrounding air speed increases. The sound becomes magnified as it transfers to the large sheet metal hood.
This noise is easily stopped by filling the coils of the hood springs with a towel or carved piece of foam. To produce what a difference this makes, tap your hood spring with a hand tool and listen to the echo. It does not occur when the coil is filled with material.
In recent years seeing the unusual Chevrolet Longhorn or similar GMC Custom Camper (1968-1972) has become a very rare occurrence. These oversize pickups, with 8 1/2 ft. bed floors, were built for work and thus there is a very limited survival rate. Most seen today started life as they were advertised carrying a vacation camper. They were usually more taken care of during their beginning years and the camper protected their wood bed from weather. Later in life, their heavier rear suspension caused them to be used more as a work truck.
The creation of this large pickup relates to GM’s trend of keeping down costs on what they suspect will be a low volume vehicle. With limited parts investment and by using pre-existing components, this new model was born in mid 1968.
The chassis had already been in existence since the beginning of the body style in 1967. It’s 133″ wheelbase was used under the 1967-1968 1 ton stepside pickup with leaf springs. Most of the components of this new Longhorn fleetside box had also been used on the earlier pickups. To create this new longer fleetside bed, GM simply produced a pair of six inch vertical bed extensions to place between the pre-existing sides and front bed panel. This filled the gap created in front of the bedsides when the 127′ wheelbase chassis was extended to 133 inches.
An expensive metal floor was not a part of this new longer fleetside pickup. A traditional wood plank floor with metal bed strips kept GM’s cost at a minimum.
To draw attention to this larger pickup, the Chevrolet division included ‘Longhorn’ die cast chrome letters secured at the rear of the sides. GMC’s designation was ‘Custom Camper’ and these letters are on each door above the chrome handle, not on the bedsides. To make it a little confusing, GMC also used these Custom Camper emblems in the same location on their heavier 3/4 ton, 127″ wheelbase pickup, with leaf springs. This shorter long bed could be obtained with either a wood or metal bottom bed.
When the optional deluxe upper trim was ordered on this long bed, it’s new six inch extension was placed to the rear of the bed. The resulting trim joining point was therefore not in line with the vertical bed extension joint at the front.
By altering suspension components both the Chevrolet and GMC 133 inch wheel base pickup could be ordered with either a ¾ or 1 ton rating. These special trucks were available from mid year 1968 through 1972. They were not continued with the introduction of the new 1973 body style.
Upper trim joint at rear of bedside. (above)
The Following is reprinted from the May 1969 issue of Motor Trend
Article byV. Lee Oertle
Why would anyone lay down $4,549.45 for a slick-looking pickup truck, even if they do call it the Longhorn? That kind of money will buy a Chevrolet station wagon, or an Impala or an SS Chevelle. That question nagged me the day a Chevrolet official handed me the keys and turned me loose in a new Longhorn pickup. When I asked a Chevrolet truck salesman the same question a few days later, he replied:
‘You’re talking about a window-sticker price, buddy. The actual base of a Longhorn pickup is $2,738 plus destination charges. The rest of it is locked up in accessories and quite a bit of optional equipment. Look at the list ‘ air conditioner alone is $392.75. Then the Turbo Hydra-Matic adds another $242.10, and the Custom Sport Truck package jacks it up another $247.50. And then; At that point, I waved him away, ‘Yeah, yeah ‘ I got eyes. I just didn’t read the fine print.’ I said, testily.
The salesman’s lips tightened a little. ‘The time to read fine print is before you buy ‘ not after.’
Good advise. Further down the sticker price list I noted that power steering on the Longhorn was $113.50. Another stopper was the $80.40 for a spare tire and wheel. On a deluxe pickup, I sort of, well, expected that a spare tire and wheel would be standard equipment. But then, I hadn’t really done my arithmetic. A quick refresher course proved that of the original sticker price of $4,549.45, a staggering $1,811.45 of it covered extras, accessories and options. Freight, license, sales taxes, carrying charges on the loan and insurance might easily push the final tally over the brink of $5,000. That’s an expensive neighborhood no matter where you live, and if anyone is tired of reading about the prices before he hears about the performance, he’ll know how I felt when I finally got behind the steering wheel.
As I rolled off the Chevrolet lot, the salesman parted with the words, ‘who buys the sticker price, anyway?’ I suppose that’s true.
From the moment a shopper takes his first walk around a Longhorn, he’ll know it’s not just another pickup. As a matter of fact, he’ll notice that it’s a longer walk. The wheelbase is up to 133 inches on this model and the cargo box is a full 8 ½ feet in length. For those not familiar with pickups, the standard pickup (any brand) has an eight-foot cargo box. The extra half-foot was added by shoving the regular cargo box along the frame ‘ and then by inserting a short panel at the forward end of the box where it intersects with the cab.
Why all the noise over a slightly larger pickup? In order to understand the significance of this, remember that any change to basic dimensions on a truck involves tremendous expense and/or ingenuity on the part of cost-cutting engineers. It’s bigger, yes, but the clever way the job was done probably hasn’t increased its construction cost very much. The next logical question would be, why? Why a longer wheelbase, for example? Anyone knows that the longer the wheelbase trucks require more turn-around space.
But, looking at it from the Chevrolet viewpoint, a longer wheelbase also improves the ride, offers a more stable platform, and makes a much better carrier for all kinds of loads. This obviously affected Chevrolet’s judgment. For instance, a suburban home owner will like the big cargo box for hauling a variety of material. The tailgate drops down to provide about 10 ½ feet of load length platform.
In case anyone wonders about how the suspension system can handle the extra length, here is the message printed in Chevrolet literature on the subject: ‘Because it’ll be carrying larger loads than other pickups, it’s been especially engineered for extra support and better balance all along its 133 inch wheelbase. Its rear suspension, for instance, is built around tough two stage leaf springs for steadier going and surer handling.’ (Coil spring front suspension teams with the rear leaf springs.)
The Longhorn is available with five different engines and several different transmissions. Our test truck was equipped with a 396 cubic inch V-8 rated at 325 horsepower. (the other engines include the standard 250 cubic inch 6, a 292 cubic inch 6, a 307 cubic inch V-8 and a 350 cubic inch V-8.)
The Longhorn bench seat is a firm, comfortable, non-slip type that gives the driver a feeling of command. It is neither too high for comfort nor so low that shorty-drivers have to stretch their necks. The instrument panel includes a tachometer, speedometer and functional oil and temperature gauges.
Start the engine and a muffled growl, low and strong, comes lightly through heavy cab insulation. Step on the accelerator and the Longhorn instantly takes hold. While 325 horsepower doesn’t sound too exciting in a passenger car, in a pickup it can be hairy under a lead foot driver. Lightly loaded, the Longhorn still hangs on tight right up through the gears. Surprisingly, there was little wheelspin except on wet streets after a rain.
I had no stop-watch with me but I know that the Longhorn will probably be the first pickup up a steep hill. Meant more for power than speed, the 4700-pound Longhorn nevertheless comes on strong in situations where it really counts. A pickup with a smaller engine, for example, often has a difficult time entering freeways. But the Longhorn gets right out there despite a ton of hay riding the cargo deck. In the hands of an amateur an empty pickup would be a handful. Crank it on too fast, too often, and the rear wheels will chirp or slip-grab as they try to deliver traction faster than the lightly-loaded rear tires can bite the pavement.
Our particular test truck had the optional three speed Turbo Hydra-Matic transmission. As far as I’m concerned, no other transmission makes sense with this combination of truck, engine and load ability. Shoving a stick-shift unit into the Longhorn makes about as much sense as hitching up an elephant to a pony cart.
Underneath, our test unit was wearing a Maximum Traction differential and an axle ratio of 3.07:1. Chevy rates this combo good up to about 7000 pounds. For loads over 7000 pounds, they suggest the optional ratio of 3.54:1. Though we didn’t tote anything exceptionally heavy, we found the 3.07:1 ratio an excellent choice for normal driving.
In this department, the Longhorn gets unusually high marks. It has a square-cornering ability few sedans can match and a sure-footed stance that keeps it straight when braking or lane-changing. By adding just 200 or 300 pounds of weight near the rear of the box, the pickup handles even better. )Extra weight cuts down on wheelspin.) Overall, the Longhorn is a solid-feeling pickup that any driver will appreciate.
There’s more than enough power for any load situation. The 396 is currently the largest engine available in a factory pickup (in any brand). The Longhorn should make a great carrier for a half-dozen trail bikes, for towing a boat, or for hauling a rented coach now and then. The luxury interior and comfortable cab will probably lure many new buyers away from station wagons and sedans. If you haven’t tried the new breed of pickups, you’re missing a most versatile family vehicle. The Longhorn is a smooth newcomer that undoubtedly will spark a host of imitations. It offers the longest wheelbase and largest cargo box of any two-door pickup, plus larger engines than competitors. As for the price? Well, like the man said: ‘Who pays sticker price, these days?’
Lest anyone suspect that I’ve been on the Chevy payroll, I have a few reservations about the Longhorn. For one thing, window glass on the driver’s side liked to slip sideways and climb up outside the channels every now and then. My guess is that the glass is a little too small for the track, or the channels were misaligned. On cold mornings, I’d climb into the cab and then, with one breath, all the windows frosted over. The longhorn is one of the few truck-cabs I’ve tested that would not clear up with the vent-windows cracked open. Steamy vapor clung stubbornly to the inside of the windshield. The only way to clear it away was to turn on the defroster full force, roll down one window, or both. On a cold morning, neither method pleased us very much.
From a purely personal viewpoint, I found it strange that Chevrolet would spend so much on interior design, but so little on panel coverings. The cab ceiling and much of the door panel areas were bare metal. Now, in a work-duty pickup that might be practical. Metal is more durable than plastic coverings, obviously. But in a class-type pickup, which the Longhorn most definitely tried to be, I found it objectionable. (There, it’s off my chest.)
We hope the following information on Axle, Transmission and Model identification will help many of you with your questions. Accuracy was a concern as we compiled this information. Because GM made so many scheduled as well as unscheduled changes, there is much discussion about these changes.
The following is used by permission from Pickups and Panels Magazine and artist Bryant J. Stewart
½ ton El Camino (6 cylinder)
½ ton El Camino (V-8)
½ ton Custom El Camino (6 cylinder)
½ ton Custom El Camino (V-8)
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup
¾ ton longbed step/fleetside pickup, panel, Suburban, 8′ stake
1 ton longbed step/fleetside pickup, 9′ stake rack
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup, panel, Suburban
¾ ton longbed step/fleetside pickup, panel, Suburban
½ ton El Camino (6 cylinder)
½ ton El Camino (V-8)
½ ton Custom El Camino (6 cylinder)
½ ton Custom El Camino (V-8)
½ ton Blazer 4×2 (1970 only)
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup, panel, Suburban
¾ ton longbed step/fleetside pickup, panel, Suburban, 8′ stake
1 ton longbed step/fleetside pickup, 9′ stake rack
½ ton Blazer 4×4
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup, panel, Suburban
¾ ton longbed step/fleetside pickup, Suburban
½ ton El Camino (6 cylinder)
½ ton El Camino (V-8)
½ ton Custom El Camino (V-8)
½ ton Blazer 4×2
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup
¾ ton longbed step/fleetside pickup, Suburban, 8′ stake
1 ton longbed step/fleetside pickup, 9′ stake rack
½ ton Blazer 4×4
½ ton shortbed step/fleetside pickup
½ ton longbed step/fleetside pickup, Suburban
¾ ton longbed step/fleetside pickup, Suburban
Disclaimer: This truck I. D. information is correct and complete to the best of our knowledge and is only to be used as a guide. Pickups ‘n panels and/or the National Chevy/GMC Truck Association, and Jim Carter Truck Parts, make no guarantee of accuracy, and disclaim any liability incurred in the use of this information.
These years are the ‘last of the breed’! Due to the increasing popularity of the new G-series van, panel truck sales had continued to suffer since the mid 1960’s. By 1970, General Motors panel truck production came to a halt. GM did not even wait until the end of the body series in 1972! This ‘enclosed body on a pickup truck chassis’ (used over 50 years) was now history.
If you ever see a 1967-1970 Chevrolet or GM panel truck, tip your hat. You are looking at one of the few survivors that were once seen everyday in residential neighborhoods making deliveries.
The first year of the 1967-1972 series of trucks had various characteristics that were unique to just that one year. For the perfectionist, 1967 GM trucks are always a challenge. Because the 1967 GMC trucks sold in smaller numbers finding one with most of its original components is unusual. Even rarer is locating a GMC Super Custom. Trucks at that time were still considered more for work than pleasure, so few put the additional money in the extra trim.
The 1967 GMC Super Custom in these photos is one of the better examples of this top of the line model. This pickup is owned by Martin Trefz in Lake Lotawana, MO. It was repainted the original red several years ago and unfortunately had its wheelwell and side trim removed at that time. Most everything else except the non original wheels remain factory installed.
The 1967 grille stands out as different than other GMC’s in this six year series. From 1968 and newer the GMC letters were placed on the nose of the hood and not stamped in the grill.
On the deluxe models, the unique one year only “Custom” die cast emblems were displayed on the front fender. These are now very rare and were often removed during a repaint or minor restoration because of surface pitting and lack of new replacements.
Of course, as with other 67 makes, there are no side marker lights. Federal regulations made these necessary in 1968 and up. Thus, fenders on 1967 are one year only.
During this first year, only the deluxe cabs had upholstered door panels instead of bare metal. Instead of vertical pleats as the Chevrolet CST, the GMC Custom runs their pleats horizontally. This was the final year that both of these makes used the same arm rests that had been on GM trucks since 1964.
Like the 67 Chevrolet, this year GMC, did not have chrome edges on the dash cluster. The coloring is reversed from the Chevrolet on its plastic dash cluster. The outer edge and inner rings are black. The flat surface is charcoal gray. The metal glove box door is matching colors.
Even on this Custom model, the outside mirror arms are body color, not chrome. The steering wheel is deluxe only because of the clear plastic horn button. Below its clear surface is a chrome disc with GMC letters, just try to find a horn button like this at any swap meet.
Because it is a custom, it comes with a big rear window. The other 1967’s have a much smaller glass here. Stainless trim surrounds both the front and rear window. The wing vent assemblies are trimmed in stainless, not black as on the other models.
One very unique feature on both Chevrolet and GMC in 1967 is the chrome wing vent handles. They are a carry over from the 1960-1966 series. The stud assembly attaching these handles wraps around the wing glass edge. There is not a stud hole in the glass as in 1968-1972. Therefore, this glass is a one year only item.
Even on the Custom (and the Chevrolet CST) the horizontal chrome strip on the hood edge and the front fender tips did not come out until 1968.
GM step beds during 1955-1966 are almost the same. They even use identical tailgates. Thus GM did not find it necessary to change the rear bumper stamping during these 12 years. However, there is one important difference which distinguishes the 1955-1959 from 1960-1966 rear stepbed bumpers.
During 1960-1966 GM placed two stamped square holes (not in 1955 through 1959) on either side of the center dip below the license plate. This is because the later series had their license plate bracket attached to this bumper, not to the rear bed cross sill as in the earlier 1955-1959
On the task force body style, 1955-1959, the GMC hoods began quite different than Chevrolet. Beginning in 1955 a large opening, 5.25″ x 25″, was used to hold a set of die cast GMC letters attached to a decorative grill.
In 1957 this grill was removed in place of a perimeter ring. Why the less attractive ring was added is a question. Possibly this grill held leaves and restricted some air intake or maybe it was a change just to be change. There was no hood opening in these last two years of this series.
By 1958-1959 GMC and Chevrolet shared the same design hood with only trim differences.
As per GM, accessories during the 1930’s through mid 1960’s were the extra cost items sold and installed by the approved dealer. The truck was prepared for these during production so the dealership could later add them with less effort.
As much as possible GM would punch holes, attach removable plates, press in dimples, etc. to help the dealership in placing the accessory in just the right position. Several accessories using the pre-placed holes or dimples in these early Chevrolet and GMC trucks are the right side taillight bracket, fresh air heater, radio, front bumper guards, cigarette lighter, arm rest, glovebox light, and windshield washer.
Options were added at the factory. They were more difficult to install by individual dealerships and were therefore placed on the vehicle during production. This included items such as a chrome grille, 4 speed transmission on 1/2 and 3/4 ton chassis, double action shocks, tinted windows on 1953-55, two speed rear axle on larger trucks, double action fuel pump, hydrovac power brake, etc.
Of the many differences between the Chevrolet and GMC 1/2 ton during the early years (1936-54), the GMC offering of a long bed pickup box was one of the more noticeable. Only GMC provided this option. To obtain this extra bed length on a Chevrolet, the buyer ordered a 3/4 ton.
This difference existed with the first GMC pickup in 1936 and continued through the end of the Advance Design series in 1955. Possibly the reasoning for this was the horsepower difference between these two marquis. The base 216 six cylinder Chevrolet engine provided 92 hp. The standard 228 GMC six boasted 100 hp.
To get the approximately nine inch extra GMC chassis length not only were the two frame rails longer but the drive shaft was extended. GMC engineers did this by developing an extension which was the connecting length between the standard short bed closed drive shaft and the rear of the transmission. None of this interchanges with a Chevrolet and both makes use a totally different drive shaft design on their 3/4 ton series.
The adjacent photo shows this unique connector link installed in its GMC. A 7 3/8 inch steel jack-shaft is surrounded by a cast iron housing (it is still a closed drive shaft) and includes an extra u-joint, bearing, and seal. Though, a strongly built drive shaft system, this portion becomes the long bed 1/2 ton’s weak link after 50 years of use and abuse. Without a doubt this link has performed almost flawlessly beyond the miles expected by its designers. However, it does have its long term limitations. The many prior miles, lack of regular maintenance, and occasionally overloading the truck makes the failure of an original in today’s world a definite possibility. Watch for sources for the rare replacement parts in this connector link just in case. Otherwise surprise damage in this area can keep your GMC 1/2 ton long bed out of service for quite some time.
Prior to the mid-1930’s, the two truck divisions of General Motors, Chevrolet and GMC, were mostly independent companies. If you wanted a 1-1/2 ton and smaller truck, Chevrolet (since 1918) could provide the model just right for your needs. If you needed a 2-ton and larger, GMC was the division to contact. They had been a large truck specialist even before 1920.
A gradual overlap began in mid-1936 with the introduction of the new “low cab” body. GMC brought out a line of light trucks in direct competition with Chevrolet. They were to give their struggling GMC dealerships additional sales during the Great Depression by fulfilling their customer’s light duty hauling needs. These new trucks shared most sheet metal with Chevrolet as well as transmissions, front suspension, wheels and differentials. A few minor changes were the grille, hood sides, lettered tailgate and hubcaps; however, the major difference was the engine.
We have heard from several sources that this first GMC 1/2 ton pickup was always a long bed of 126”. The short bed 112” was not available until 1937.
At that time GMC did not produce a small engine that could fit their new light duty trucks. Their totally new small six-cylinder overhead valve power plant was still three years away. The solution was to use a pre-existing engine from one of the General Motors other divisions. They adopted the 213 cubic inch six-cylinder flat head (valves in the block) engine from Oldsmobile. Its power, size and reliability in cars made it the best choice and replacement parts were already available from the Oldsmobile division.
This proven engine in combination with the new low cab body proved successful and allowed GMC to begin gaining ground in the small truck market.
This 213 full oil pressure insert bearing engine (updated by Oldsmobile in 1937 to 230) was main source of power during the early years of smaller GMC trucks, 1936-38. One exception was in the half-ton pickup in 1938. For this model and year only, GMC now used a different smaller flat head six-cylinder. It came from the Pontiac car division and it even has the Pontiac Indian head symbol cast in the right side of the engine block. It had 223 cubic inches. The 230 was retained on GMCs larger than 1/2-tons.
Few of these light duty GMC survive today. They not only experienced the usual heavy work jobs as trucks, but with World War II new truck shortages meant few GMCs were set idle in storage. After the war, most were worn down to where it cost more to repair them than using them to make a down payment on a new truck. Thus, the majority were lost to the crusher.
1937 GMC, Drawing by Bryant Stewart, Farley, MA.
1936 GMC T-14
(Photo compliments of Patrick Kroeger at firstname.lastname@example.org)
Not to be used without written permission.
In contrast to 1954-1955 Chevrolet trucks, the same year GMC had a position in the dash for an optional gauge. It was here that larger GMC’s had a tachometer or vacuum gauge installed. The 1/2, 3/4 and 1 ton GMC’s usually did not require these engine gauges and a blank-out plate is normally found there. An option here in these smaller trucks is a spring wind clock. It was produced by General Motors and installed at their GMC dealerships.
1954 GMC dash with clock installed (above)
To save production costs, GMC used the clock that was already on the 1953-1954
Chevrolet car. In this way, their investment was limited to a chrome adapter ring that fit in the opening that held the blank-out plate.
This chrome ring has recently been reproduced and is available from most full stocking dealers including Jim Carters Truck Parts. Restorable 1953-1954 Chevrolet car clocks are found at most any medium size automotive swap meet.
The following is from a 1954 GMC accessories catalog. Their wording tells the 1954 story in a full page ad.
Prior to the 1960’s, trucks were used as work vehicles. On Friday nights, most were parked for the weekend and the family sedan was the transportation vehicle.
It was a conservative era when you bought only basic necessities. A $5.00 grocery purchase was more than most could carry. Finding white wall tires on a truck (even a car) would have been a rare sight, indeed. Very few cars, except for most luxurious models, would have had white walls even as an option. It should be remembered, that most roads, except highways and those in the main part of town were gravel, dirt, or sprayed annually with tar.
Of course, a dealer would have been happy to install aftermarket white wall tires, if the customer made a specific request. For a price, the dealer would provide any option to keep a satisfied customer and make a few dollars.
On GM trucks, white walls became a factory option in mid-1955, partially because of the introduction of the Chevrolet Cameo and GMC Suburban carrier and also due to more roads becoming paved. These very deluxe pickups, as well as several of the other well appointed 1/2 tons justified a white wall tire for those wanting it all!
Almost none of these deluxe models would have been given their second set of white wall tires. By then, the pickup was older and being used more as a hauler, not for appearance.
The 1947-1955 Chevrolet and GMC came from the factory with left mirror arms on left hand drive trucks. This was particularly important if the truck was to have a large bed that covered the rear window.
To keep sale price low, the right mirror arm was an accessory (dealer installed). It was very important that the dealer place the mirror just right so the actual mirror was viewed by the driver through the lower right corner of the windshield.
To prevent dealer mistakes, GM placed an inner panel in all trucks covering the area were the two holes would be placed. This panel had factory holes, showing the mechanic where to drill. Thus, two exterior holes could always be in the proper place. Yes, the glove box liner would be removed to make room for the drilling.
Chevrolet linkage-type power steering is now available optionally on Series C10, 20, 30 models. This was formerly a dealer installed item. The equipment consists of a hydraulic pump, power cylinder, control valve, relay rod and hoses.
The power cylinder is mounted to the frame and is connected to the control valve through the hoses. The control valve is mounted on the steering drag link between the knuckle arm and the steering arm and it serves to control the flow of pressurized power steering fluid to either side of the power cylinder piston. This in turn pushes or pulls the tie rod as required for easier steering.
Power steering helps to combat driver fatigue and aids maneuverability. It also dampens road shocks and vibrations at the steering wheel and provides extra comfort and ease of handling.
With the introduction of the new small block V-8’s in 1955 Chevrolet trucks, modified sheet metal was created to help in cooling. The new truck design came standard with the proven 235 inline six cylinder but when an optional V-8 was added, cooling modifications were necessary.
The short length V-8’s cooling fan was too far from the radiator and could pull air from above and below the engine and less through the core. To prevent this, all V-8 trucks came with an upper and lower metal baffle plate to help better pull air through the radiator.
These metal plates have become very difficult to locate in recent years. The lack of these two plates on (restored?) V-8 trucks are usually a strong indication the vehicle has been converted from an original six cylinder. The mechanic was either not aware these plates existed or had no idea of where to locate them.
During 1958-1959 the shroud was redesigned. It became a more traditional metal circle as is found on more modern vehicles. This allowed even more air to be pulled through the radiator core.
The following photos show original Chevrolet radiator cooling sheet metal from 1955-1957 V-8 trucks. The dark lines on the drawing relates to how these plates fit in the original vehicle.
We often get requests for a formula to make the Advance Design pickups more freeway friendly. Their original ring and pinion gears were created to make the truck’s six cylinder work well with a load and also keep up with the 1950’s traffic on gravel roads and two lane paved highways.
Though a higher speed reproduction ring and pinion was introduced several years ago, some owners still ask for another alternative to get in the “fast lane”. One method has been used successfully for several years and requires most parts from local salvage yards. Obtain the Borg-Warner 5 speed overdrive transmission from an S-10 pickup. It must come from an earlier model with a mechanical speed sensor (on the side of the case). It can not have the more high tech electronic speed sensor as used on the later S-10 pickups with computers.
This transmission will bolt against the original bellhousing of a 1948 and newer (a nice surprise). The clutch shaft which extends out of the front of the transmission is usually too long to allow the ears to bolt flat and secure to the bellhousing face. Therefore, if this occurs, shorten the tip of the shaft about a half inch and all will fit together. This is a must. Otherwise you can even break off a transmission ear when you begin tightening the four attaching bolts.
The ears that attach the transmission to the bellhousing are usually drilled for a metric bolt. They will need to be enlarged for a standard 1/2 inch bolt as is threaded into the bellhousing.
The V-8 Camaro 5 speed transmission is also similar to the S-10. It is said to not be as low geared and this makes it more desirable. The Camaro shift lever is too far back for the 1948-59 pickup. The bench seat is in the way. To correct this, use the S-10 tail shaft housing and case top cover. This will allow the vertical lever to come through the original floor in the correct position.
The input shaft of the 5 speed will have either 14 or 26 splines. Therefore, the clutch disc must match the transmission and not the 10 splines from the original 1948-1959 truck.
The attractive S-10 boot is still available from GM and the shift knob of choice is from a late model 5-speed Jeep. It screws on perfectly and looks great! The S-10 shifter clears the seat cushion and looks like it was installed by GM.
The next step is the differential. An open drive shaft style will be necessary to match up with the 5-speed but this is a subject for an totally different technical article.
The result of this change is lower RPM’s and speed to keep up with traffic flow on most modern highways.
The Trials and Tribulations of Installing a GMC 302 engine into a 1950 3/4 ton Chevrolet Pick Up
by Joel Baumbaugh
Background: About 5 years ago I “upgraded” the engine in my truck from a 216 to a 235. Lately I have felt that I wanted/needed a little more torque (especially while the bed is full of something heavy) and while one option was to rebuild and re-cam my 235 and another was to install a Chevy 350/400 (or 700R), the “popular” literature said that I could also install a GMC 270 or 302. Just to be “different”, I decided to go the latter route.
The Source: I wanted a “running” engine that I could just drop in with a minimum of trouble. The engine I found for my project was a 1959-1962 GMC engine from a School Bus. The bus had been converted into a “camper” and had then caught on fire and burned beyond repair. At first glance, the outside of the engine looked kind of rough. I checked the compression (all cyls. were at 160 lbs./sq.in), looked at the plugs (all light brown), listened to it run (no strange noises) ‘ the oil pressure was 55-60 lbs./sq.in. at idle and the rocker arms/valve area was pretty clean of sludge. Short of pulling the pan, this was as far as I could go. I bought it, brought it home and cleaned it up.
Problems/Solutions: The engine had a LOT of bus-type accessories that I did not want/need. The “massive” front Crank Pulley (the damper pulley assay) had a three-groove pulley ‘ “way” too long! After careful measurement I found that I was able to replace it with a single groove pulley off of a 235 (I replaced the front seal at this time). The water pump shaft was “very” long as well and sported a 2-groove pulley. I removed the pulley and ground/cut the pulley shaft back. The water pump on this engine did not seal against the block and/or head. This one was bolted to a thick steel plate which held a tensioner (for a double groove pulley) which weighed about 30 lbs. (weight I did NOT want) and was bolted to the front of the block. I found a rear plate (and gaskets) for the water pump from a place here in town that rebuilds water pumps. Bolting the water pump directly to the block saved me another ½ inch in engine length. The owner also sold me a flange to press on to the shaft so that I could bolt a new water pump pulley onto the pump (the original Chevy is shaft diameter is ½ inches and the 302 is 3/l8 inches). To find a pulley which would align with the bottom crankshaft pulley required a number of trips to local junk/wrecking yards. I finally found one that was the perfect depth (I’m not sure if it was originally from a Chevy or not). I had to enlarge the center hole to make it fit the GMC shaft.
The 302’s “bus” generator weighed about 80 lbs. I found that the 235’s generator mounting flange’s bolt-holes fit perfectly! However, I “did” need to reverse it and then elongate the mounting holes so that I could slide it forward to align the generator pulley groove with the crank and water pump pulleys.
The carburetor that came with the engine was a joke. It even had a governor on it. I had the option to purchase a better 2-barrel carburetor or to step up a little bit and buy a 4-barrel manifold. I did the latter. I had a (gasp) Ford ‘Autolite’ carburetor in my garage (about 400 CFM) from a ‘289’ which I bolted up to the manifold and it works GREAT! – Especially with the stock low-performance camshaft. I also at this time “upgraded” my carburetor linkage. I went to an off-road dune buggy place and purchased a new accelerator pedal and a push-pull cable. Configuring the carburetor linkage from the stock pedal to the new manifold/carburetor would have been a nightmare otherwise.
Radiator: The 302 engine “is” 1 1/2 to two inches longer than the 325 (which is longer than the 216). This means that the radiator no longer fits into its original location. I tried to modify the radiator mount to put the radiator inside. Don’t even try. The radiator needs to mount on the front of the mount. This means that you will have to borrow your neighbor’s “Saws-All” with a metal cutting blade and cut away the top and front cross bracing on the radiator support, the lower front wind deflecting metalwork at the bottom (behind the grill) and drill 6 new holes in the mount for the radiator. The upper support that contains the hood latch will need to have a rectangle cut in it to fit the top of the radiator in it as well. I now have about 2 inches clearance between my water pump pulley and the radiator. I use an electric thermostatically controlled (pusher) fan in front of my radiator. It’s quieter, doesn’t rob the engine of power (better mileage) and the water pump may last longer without the fan blades. Note: My friend and neighbor has a 1951 GMC. I have measured his engine compartment. From his bellhousing to the radiator flange he had 4 more inches to play with, so I’d bet that he originally had a longer GMC engine (he runs a Chevy 235 now), and that he could make the conversion to a 270 or 302 without any cutting being necessary.
Front Mount Yes the 302 engine “is” 1 1/2 to 2 inches longer than the 235. The front mount on the Bus’ 302 was a weird set-up which caused the engine to sit at an angle (like a Chrysler slant 6). This saved some height in the bus’ engine compartment. However, after removing the bus setup spacers, I found that the two bolt holes on the mount (on the bottom of the timing cover/block) were at right angles to the block and aligned perfectly with my truck’s original 216 mount so I was able to exchange them and everything was level ‘ no oil pan removal required! I then drilled two (new) holes through the truck’s cross member, put in longer frame-mounting bolts and added some extra rubber padding (cut from a truck mud-flap) to keep the mount from rubbing on the frame and so far its worked ok.
Rear: The bus engine I purchased was coupled to an automatic transmission. That meant that it had a flex plate (that the converter bolted to) instead of a flywheel. The flex-plate (with the old ring-gear) was MUCH larger than the flywheel I would need. I found a flywheel from a GMC 270 that fit. Although the flywheel’s diameter and the number of teeth are the same as the 1955-1959 Chevrolet, the crankshaft bolt pattern is different between the GMC’s and the Chevrolet’s. The flywheel bolts are different as well (1/2 inch dia. instead of 3/8’s”). Although I tried using an impact wrench, a gorilla on steroids must have put on the old flywheel bolts. I broke a socket and finally had to remove 3 of them with a chisel. The 3/8″ GMC flywheel bolts are not available ANYWHERE. I went to an industrial bolt supply place and bought six more grade 10 bolts. I had the heads machined thinner (like the originals) as otherwise they protrude into the pressure plate/clutch plate area and will cause binding problems. I then carefully shortened the bolts (watch those threads ‘ I put a tap on the inside of the bolt and then backed it off to remove the burrs) to match the original length as they otherwise hit the block behind the flywheel (close tolerances here…).
The pressure and clutch plates and throw-out bearing match those of a Chevy 1955-1959 10- inch set. The 302 had a roller bearing pilot bearing instead of a oillite bronze bushing. I replaced it with another roller bearing and the transmission (its a Saginaw off of a 1969 Camaro) fit in just fine.
I used my original bellhousing off of the 1950 Chevy. The old GMC one was slanted to match the front motor mount. The starter location in the GMC bellhousing was for a larger diameter flexplate and would not work. The GMC starter had the wrong number of teeth to work on the 10″ flywheel. The starter which (I found) works, was a 12 volt 9 tooth (for a 164 tooth flywheel) from a 1955 Chevrolet and works great.
Oil and Water lines: There is an oil line on the front of the block up to the head. This supplies the oil to the rocker arms. Leave it alone. I tied (T’d) into it and put on a 100 PSI oil pressure gage as my Chevy gage only goes to 30 lbs. This engine NEEDS an oil filter. If you block off the oil supply line on the driver’s side of the block you will not get ANY oil pressure in the engine. I “T’d” into the pressure side and connected up my original oil pressure gage (it’s a stretch, but it reaches). Yes, it’s always pegged on 30 lbs., but gives me a warm fuzzy feeling when I look down. The head has an external water line that goes to the thermostat housing. Leave it alone. You can put a “T” in and hook up your temperature gage (with an adapter), but I put mine further down on the block (there’s a fitting there), because it was always showing “cold” on the gage. Be careful of that temperature gage line. It cost me close to $50.00 the last time I had to replace it. The radiator hoses clamped right up although the GMC diameter on the lower radiator hose is one step smaller.
The 302’s distributor had a governor on it and was centrifugal advance only. The bottom of the distributor was different than the Chevy, but my Chevy distributor “guts” bolted right in. I was able to put in a spring kit (the GMC centrifugal advance springs were so thick that they could have been used for front struts on a Honda) and I now have vacuum advance as well.
The GMC fuel pump leaked so I replaced it with a Pep Boys electric fuel pump. I couldn’t find a replacement anywhere locally, so I guess I’ll have this one rebuilt for a “spare”.
I had a split cast-iron exhaust manifold on the Chevy 235. I “may” get a header for this motor in the future, but in the mean time I had the muffler shop split the 302’s three-inch header pipe into the two existing exhaust pipes.
And, how is it?
Well, pretty good. I have a LOT more torque. This means that I can get up to freeway speeds without wishing for bike-pedals for a little more push. I have 36″ tires on 6″ Chevy rims on the back so I’m only turning 2,800 RPM at 60 mph. The larger tires had made the truck a little “logy” getting started with the 235 ‘ now it “steps right out” from a light. I haven’t checked the gas mileage yet. I was getting 17 mpg City and 20 mpg highway with the old 235. I’d guess that I’ve lost about 2 mpg with this engine/carburetor combination.
Future When this old engine is due for a rebuild, I’ll probably buy some “lighter” pistons and a little hotter (than stock) cam. The pistons will help the engine “rev” faster, be easier on the bottom end and will probably result in higher gas mileage due to their weight difference and the higher compression. The cam will help volumetric efficiency and give me a little more torque and higher end. Of course I’ll have everything balanced ‘ IMHO it’s worth the extra money.
I hope that this story helps someone else. Remember the 270 and 302 are “basically” the same engine so I imagine that your situation will be pretty similar to mine no matter what you find. It took “6 hours” using hand tools to remove the old engine and 4 days to put back in the new.
Since the project above, I decided to rebuild the 302 as it was burning a little oil. I bored the cylinders out .125 thousands (it’s now 320 cubic inches), put in a “Patrick’s” M4F camshaft, and put in “Venolia” 10.5×1 forged pistons. I had everything balanced of course. I had to find and purchase another head as the old one had a crack in it (hence the oil burning). When I got the new (used) head, I pulled out the valves and cleaned/smoothed up the intake and exhaust ports/passages which were pretty rough castings, and then put in new late-model exhaust valves (I went to 1.5″) and hardened seats for unleaded gas, and I’m using Chrysler “440” valve springs. I’m now running a “Holley” 600 CFM carburetor (vacuum secondaries) with “Fenton” cast-iron headers. When first started up on a dyno (and not really broken in yet) it recorded 286 hp and 362 ft/lbs torque; not bad for a “street” engine; At this time I also put in a T-5 GM transmission from a ’91 V-8 Camaro (the V-8 transmission has better bearings to handle the torque) with a tail-shaft from a S-10 Pick-up (the shifter was almost in the same place) – so now I have a 0.74 overdrive. At 75mph (a fender-slapping speed for the old pick-up) I’m only turning 2,100 RPM; I had a new driveshaft made as the transmission yoke splines on my old one looked worn.
So far, I’m pretty happy with my set-up. Happy “wrenching” everyone;. ..jb
This is my latest project a 1937 GMC 1/2 ton pickup. Not exactly original but a personal preference. The previous owner had owned the truck for over 30 years and finally parted with it. It had been restored many years ago but was in need of a lot of repair to shoddy bodywork and I have added many upgrades. So far the frame and drive line are in place and currently doing the body work. I plan on doing all the work myself. Have not selected a color as of yet. Leaning to either black or a metallic red . The truck has a 350 chevy with a B & M blower with 2-4 barrels (and it all fits under the hood) , 350 turbo trannie, 12 bolt rear, mustang II front suspension and a 4 link in the rear. Should be an head turner when finished.
Though the major cab and fender sheet metal change began in mid 1947 (Advance Design), both the Chevrolet and GMC trucks kept their same proven six cylinder engines as used in prior years.
The base engine in GMC light trucks was the 228 cubic inch inline six cylinder introduced in 1939. This overhead valve unit had a full pressure oil system with its rod and main bearings lubricated from drilled lines within the crankshaft. Their high oil pressure is reflected on the dash gauge reading 0-50 pounds.
This family of engines during the Advance Design years also produced the 248 and 270 cubic inch units. The cylinder diameter in their main difference. They all share the same overhaul gaskets, water pumps, oil pans, distributors and side plates. On GMC, not Chevrolet, the cubic inch is the first three digits of the stamped serial number on the flat surface behind the distributor.
Chevrolet’s six cylinder used during most of the Advance Design years was very different from the GMC. Its standard 216 cubic inch engine was a result of continual improvements since the first Chevrolet six cylinder began in 1929. The 1940’s 216 truck engines were almost identical to that in the Chevrolet car. Therefore, millions of 216’s were on the road by the beginning of 1947. Their basic design and easy maintenance made them one of the greats in lower priced vehicles. When used on the roads of that era, they provided dependable service both on the farm and in the city.
The 216 engine was the standard power plant in the 3000 and 4000 series trucks. Its big brother, the 235 was optional on the 4000 series and standard on the 5000 and 6000 series. It is almost identical to the 216 but the increased displacement gave the needed extra power to work trucks. The 235 truck engine was not used in pickups, however, was matched to the Powerglide transmission cars with some modifications between 1950-53.
These 216 and early 235 are designed to operate without oil lines drilled in the crankshaft to lubricate their bearings.
The early 235 should not be confused with the more famous later 235 full pressure engine first introduced in Powerglide Chevrolet cars and the Corvette in 1953. During this transition year trucks continued to have the lower pressure design. By 1954 the full oil pressure 235 became the standard of the Chevrolet fleet. It was modified for trucks by using solid valve lifters in place of the hydraulics in cars. The camshaft gear was changed from fiber to aluminum.
The door window is cranked up tight in the cloth channel and off you go on your daily errands. Suddenly, the glass begins to slowly lowers as you drive over side roads or contact a rough surface. In comes cold air, rain, and wind! Even the window handle turns. What’s this all about? Do you tape the window closed or wire the handle so it will not turn?
You have a window regulator spring problem! This large 2″ diameter round spring has either broken or become disconnected.
With no spring tension on the regulator, the weight of the glass creates the lowering of the support arm and window. Sorry, there is no good fix other than removing the regulator from inside the door. The picture below shows this circular Clock spring. It must be large to hold the weight of the glass panel.
Even if you prefer an original vacuum wiper motor for these years rebuildable cores have become very rare and most New Old Stock units are just not obtainable. Even new ones have their lubrication dry after 70 years.
For those that won’t except a slow moving or non-working used vacuum unit, an alternative does exist. New electric motors are now on the market in both 6 and 12 volt styles. The above photo shows a new unit before installation.
You will no longer need the original inside wiper cover plate with the indention. Replace it with the included non-indented style which gives a smooth finish.
The electric wires can be run inside the windshield post to a switch of your choice under the dash.
These kits can be obtained from Jim Carter Truck Parts at 1-800-842-1913.
During the early years of auto and truck design, most vehicles came with their windshields capable of tipping outward. This helped poorly insulated cabs to be more bearable during hot weather. Extra outside air would be forced into the cab and replaced some of the hot air radiating from the bare sheet metal firewall.
This idea was good but not without a few problems. Unfortunately, air movement depended on the speed of the vehicle. The faster the driving, the more air circulation. Too bad for the driver in stop and go city traffic during a hot summer day.
In GM trucks, water leaks into the cab developed as the rubber edge seal began to age. The under dash crank-out gear assembly (1936-46) was not easily reached and therefore almost never received lubrication. The gear would wear and later most became non-usable. It was then necessary to close the windshield frame permanently and the cab lost a major method of getting air flow on hot days.
The system was expensive to produce! A pair of swing hinges, a crank-out assembly, and two windshield halves added to production costs.
This windshield vent system was stopped with the introduction of the 1947 Advance Design cab. The two piece windshield now became permanently sealed. An insulated interior fire wall pad was standard. A left side cowl vent intake door forced outside air over the drivers feet and lower legs. (Of course, this was also when the truck was moving.)
A top cowl vent door (also on earlier trucks) now had a screen to prevent entry of insects. Thus, this was the end of the swing-out windshield. They were a great help on hot days when the vehicle was moving, but inevitable gear wear began a new set of problems for later years.
NOTE: During World War II, the military using civilian cabs on their larger trucks had no patience for this crank-out assembly. They wanted no malfunction in the open position while being in a Russian or German winter. They even placed the windshield hinges on the roof for less complicated repairs in the field.
Therefore, the military went back to the swing out windshield frame design that opened manually by the driver. This system was used on all 1936 and older High Cab Chevrolet trucks, Model A Fords, and so many other early automobiles that needed more ventilation. See Photos.
During 1939-40 Door window breakage on truck cabs became a problem. As the cloth fabric in the door window channel became worn, the large and now loose fitting side windows were susceptible to cracking when the door was slammed. Complaints from dealers resulted in an improvement on 1941-46 doors. A one piece metal frame was placed around the edges of the top and sides of the glass and the breakage was greatly reduced. To make room for these new metal frames, the glass on the 1941-46 doors was now slightly smaller.
Therefore, the 1939-40 door glass and 1941-46 with metal frame will interchange in total in all 1939-46 doors. The smaller 1941-46 door glass can not be used without it’s frame or it will not seal into the cloth channel at the top of the window opening.
With the introduction of the new Cameo in 1955, GM added their most deluxe features as standard equipment. This “Boulevard Pickup” was to stand out above all others.
The wheel covers were not like that on the more standard pickup. To save tooling costs on this limited production model, GM used the wheel cover on the 1955 Chevrolet Belair car. Both vehicles had 15″ wheels so the top of the line car wheel cover was chosen for the new Cameo.
1955 Wheel Cover (above)
The same procedure occurred in 1956. The Cameo carried the 1956 Chevrolet Belair full wheel cover, not the same design as 1955.
1956 Wheel Cover (above)
The big change in Cameo wheel trim occurred with the 1957 model. This was the first year for the 14″ wheels on the passenger car. The Belair cover was no longer a fit for the Cameo 15″ wheels. GM’s answer was to chrome the standard white 1/2 ton hub cap. To add more to the appearance, a Cameo trim ring was created to cover the outer edge of the wheel.
1957 1958 Hub Cap and Trim Ring (above)
With the limited Cameo production in 1958, the same wheel trim was used this final year.
The 1955 year was the first for factory installed whitewall tires. It made an excellent combination with the wheel trim. This is another major change in the GM deluxe 1/2 tons looking less than work trucks. The 15″ wheels remained the same during the four years of the Suburban Carrier. GM just chromed the small standard hub cap. No wheel ring was used as standard equipment, however the wheel was given a contrasting light color.
During the early years of GM truck production, many examples exist which relate to their vehicles being designed more for work. Changing a trim part for appearance reasons was usually secondary if it resulted in unnecessary expense. Often parts were used that had already been on GM automobiles. This eliminated expensive new tooling costs and kept GM truck prices in line with the competition.
An excellent example of this type thinking is shown with the 1957-1960 hubcaps. Even though the 1960 pickup was a totally redesigned vehicle, GM carried their older hub cap on this new pickup. The reasoning goes back to keeping truck prices low. The 1960 1/2 ton wheel was to be the last carrying the inside spring clips to secure the hub caps. As truck hub caps were used several years, it was not likely a new 1960 design would be created for only one year. GM held off from using a redesigned hub cap until 1961 so that it would fit on the new non-clip wheel. To stay with tradition, this new 1/2 ton cap was then used three years.
To keep the 1960 3/4 and 1 ton hub cap appearances similar to the 1/2 ton, GM again retained the earlier style. This occurred even though the larger truck inside clip split rim wheel design was basically unchanged between 1946 and the late 1960’s.
Chevrolet and GMC each had their own different hub cab design during this time, however, they both changed styles at the same time. A full Chevrolet or GMC wheel cover was unavailable for the deluxe 1957-59 truck models. GM simply chromed their standard caps that were otherwise painted white. An optional chromed GM wheel ring could be added on the 1/2 ton series in 1957-1959 Chevrolet but not during 1960. These trim rings were stock on the 1957-1958 Cameo but dealer installed on other 1/2 tons.
In 1960, a full wheel cover was introduced on the Deluxe 1/2 Ton Package. Actually, it was from a 1956 Chevrolet Belair car and 1956 Chevrolet Cameo. Once again, GM used this stamping from five year old tooling and saved production costs.
1960 Wheel Covers (above)
Stainless Steel on the Deluxe 1/2 Ton Pickup. 15″ Wheels only.
1957-1959 Wheel Rings (above)
Chromed steel wheel rings that blend with optional chrome hub caps to give appearance of full-chrome wheels. 15″ wheels only.
During the 1940’s through 1950’s placing pin stripes on automobile wheels occurred on most all brands. It was an inexpensive touch that added a little flair to the appearance of a new wheel. The stripe could be added quickly with a machine on a rotating wheel. The factory didn’t need a human as on the body stripes.
GM was no exception. They had been striping most new car wheels for almost 10 years. Beginning with the 1947 Advance Design trucks, this striping even was used on ½ tons that had the deluxe package (not the standard models). This extra was continued through the 1947-1955 body style.
The attached photo shows a used original never repainted 16″ 1/2 ton deluxe wheel. Note how perfect the 3/4″ stripes are applied. With the addition of the small chrome hub cap, the wheel drew attention
Problem: Slop in the shift pattern on 1947 Chevrolet & GMC 3 speed transmissions.
On the first year of the 1947-55 Advance Design trucks, their 3 speed transmission was a carryover from the prior years. It remained a floor shift unit, not a column shift as 1948 and newer. When shifting into 2nd gear finds your knuckles contacting the glove box door, repairs are needed and available.
Chevrolet did not plan on these 3 speed transmissions to be in use over 50 years so repairs in this area were not often discussed by GM. You can fix it anyway!
Remove the flat plate with the shift lever from transmission by taking out the 4 retaining bolts. (Be sure to replace this plate with cloth or cardboard so no foreign object falls inside.) Take the shift tower from the flat plate top by removing four retaining bolts. The shift lever and its 2 1/4 inch tension spring can now be taken from the tower.
Inside the top of the tower is the worn brass bushing causing most of the shift lever slop. A replacement with tension spring can be obtained from Jim Carter’s Truck Parts and most of their full stocking dealers.
Sorry, exchanging the brass bushing will not solve all the problem. The long horizontal pin, through the shift lever ball, needs to be replaced. The pin will probably be worn on each end and needs replacement.
Using a drill bit is a good option for a new pin. If a 1/4 inch drill bit easily moves into the shift lever ball, move up to the next size. (Maybe as much as 9/32 inch drill bit). Use it to drill the hole oversize, then use this same drill bit as the new pin. After drilling, remove the drill portion on the bit, and you have a nice hardened pin! Note: do not cut the drill bit until you know the exact length needed. Get a correct size by turning the shift tower upside down and measuring the distance between the two notches to the tower walls.
The term artillery wheel is a nickname adapted from a scalloped type wheel often seen on US military vehicles in World War I. The similar appearance at a distance to GM’s scalloped steel wheels quickly gave them the name artillery.
On GM trucks, this style was first used during 1934-36 as a stock six bolt 1/2 ton 17 inch wheel. It was much stronger than the existing wire style wheels due to it being less susceptible to bending when hitting a large pot hole or sliding against a curb.
Though this 17 inch unit was discontinued on 1/2 tons for 1937, a redesigned 15 inch artillery began as GM’s stock wheel on that year’s 3/4 ton truck. It was stronger and wider but was still a non-split rim design. This remained the GM 3/4 ton wheel through 1945. By 1946, six bolt wheels on trucks were limited to 1/2 tons. The 3/4 ton would now have 15 inch 8 bolt split rims which remained stock into the 1960’s.
Today, we sometimes see 1947-59 GM 1/2 tons equipped with these early 15 inch artillery 3/4 ton wheels even though they were not placed on factory trucks after 1945. To many, they provide a unique appearance on the later 1/2 tons and will still hold the trucks current hub cap.
About 10 years after the introduction of GMC’s new inline six cylinder engine in 1939, General Motors issued a ‘Product Service Bulletin’ in regards to a recommended improvement on the 228, 248, and 270. It appears the manufacturer discovered a weakness that shortened the life of the engine timing gears. This recommendation was made for enlarging the oil supply hole leading to the meeting point of the two gears. The attached dealer bulletin was issued January 31, 1949.
This is especially interesting considering over a million GMC trucks with these engines had been built prior to this. The number includes the five years of military large trucks that were used during WWII under very abusive off road conditions!
From 1934 to 1959 GM 1/2 tons came from the factory with a tie rod assembly that extended side to side to almost touch the front wheels. With everything stock, the tie rod sits about 3/4 inch from the inside of both original six hole wheels and all fits just right.
A problem exists when someone attempts to add a more modern wheel. For example, the mid 60’s and newer 4×4 wheels have this 6 hole bolt pattern but their width causes them to contact the end of original long tie rod. Changing from the approximate 4-1/2 inch original to at least a 6 inch width just won’t work.
Solutions for adding a more sporty wheel are very limited with the original suspension. One almost unknown method is to replace the original GM multi-piece tie rod ends with the more modern knuckle ends introduced in the 1960’s. There are currently available and are 3/8 inch shorter on the outer end giving that much extra room for a slightly wider wheel. (It is not recommended that flat washers be placed over the stud between the wheel and drum as this can cause breakage.)
This GM six bolt pattern is also shared with several Japanese pickups. Some very attractive more narrow aftermarket wheels have been produced for their imports in past years.
What an unusual seat on the 1967-68 Chevy/GMC pickups! It was standard equipment on the “top of the line” Chevrolet CST and GMC Super Custom pickups.
The seat consisted of two bucket seats and a much smaller center cushion referred by many as a Buddy seat. It allowed for a third passenger or the back cushion could be lowered horizontally to give an oversize arm rest. When you lift the lower cushion there is a large storage area. All are covered with pleated vinyl. Yes, three pair of seat belts were included.
The three cushions contained extra foam and better springs to give the owner a more comfortable ride. These seats were part of a more deluxe cab that had not been available in prior years. We have no documentation that they could even be special ordered on the larger 1 ½ and 2 tons.
GMC Super Custom Interiors offer the ultimate in comfort and style, including plush bucket seats with vinyl covering and matching center seat concole. The GMC Super Custom also includes appearance and comfort options from special horn button to carpeted floor.
One series of the famous “drop out” GM differentials was used between 1946 and 1972 on 3/4 and 1 tons. The complete assembly (often called a pumpkin) will interchange during these years with no alteration.
The highest gearing in this series is the 4.10 ratio and is found in most 1967-72 3/4 tons with automatic transmissions. Therefore, those “low gear blues” often associated with 3/4 and 1 tons during the late 1940’s and 1950’s can be greatly improved with no visible exterior changes. Originally these older trucks had a ratio of 4.57 in the 3/4 tons and 5.14 in the 1 tons.
Once a 4.10 pumpkin is located (usually in a local wrecking yard) it is a basic interchange requiring little more than new gaskets and gear grease. Your truck’s personality is now changed!
This interchange will fit perfectly if the “complete” pumpkin is used. The 1963-1972 carrier is necessary and it will be part of this total assembly. The change-over will not work if you only use the ring and pinion.
The only negative to this changeover is if you are hauling a ton of gravel up a mountain road with the original smaller six cylinder!! In this example a lower geared differential is best.
For those not requiring the original seat cushions on their 1955-59 Task Force truck, a roomy comfortable substitute is available. This unit is from a 1988 body style Chevrolet or GMC truck and is almost a bolt-in.
The legs or side brackets on this newer seat comes attached to the cushions from a used truck and sets nicely by the floor edge of the 1955-1959 cab. It almost looks factory installed! Yes, the cushion edge will slightly touch the doors but cause no closing problems.
The result is a much softer seat and a definite increase in distance between your “middle” and the stock steering wheel. Almost no interference with the in cab fuel tank.
When you notice your head, tail and dash lights are often dim, sometimes even flicker on a rough road, check your cab to frame ground cable
Because the 1967-1972 cab and radiator supports are seperated from the frame by rubber mounts. GM used a small mount woven wire ground strap that by-passes one cab mount. This insures electrical flow even if the cab mount bolts become rusted and electrical current can not flow properly.
You must be under the cab to see this by-pass cable. Yes, GM planned for the trucks later years when rusty mounting hardware caused the lights to dim
Locating a pair of seat cushions for the 1939-46 truck has become very difficult in recent years. These early trucks increased popularity is the main reason for the shortage. Even when a pair of cushions are located the asking price often does not justify the purchase because of the age damage to the springs and frame of the lower cushion.
It is this lower cushion that has received the most wear in its 60 years. In a salvage yard the door or window left open for even a year allows rain water to soak the seat padding and hasten the damage.
As your hunt continues, here is a practical substitute that fits the cab well and gives the appearance of a re-upholstered original. Locate the common rear seat (not the middle) in a 1984-90 Dodge Caravan or Plymouth Voyager mini-van. You can even pull the factory levers on the back and the seat is quickly removed. Most salvage yards have many extras and their pricing should be under $50.00. You will even get the seat belts!
With less use of this rear seat in the van, you can find one with no tears or permanent stains.
The next step is cleaning. Simply place it in the bed of your late model pickup and find a coin operated wand car wash. The hot soapy water will make the cloth covered cushion like new for less than $5.00. Leave it in your truck for a few hours until the water drip stops. Then place the cushion where it can dry. In about 24 hours, the job is done! The padding is closed cell foam and does not absorb water.
You won’t need most of the lower metal attaching brackets. Remove them and attach the remaining metal and cushions to your trucks original seat riser. Here is where you can be creative but it is done and the remaining metal will not be visible.
For the perfectionist, the cab tapers inward as it reaches the cowl. Thus, the two doors are slightly closer to each other at the front in a standard cab. This new van cushion will touch the front of the doors because of this taper. If you don’t like this contact with the door, an upholstery shop can place a taper in the lower cushion to parallel the inside door panel. A small portion of the foam edge can be removed from the front sides of the lower cushion.
Continue to search for the original 1939-46 seat cushions. In the meantime, you have very comfortable clean cushions with seat belts. Most people will think you had your originals reupholstered.
The following article and pictures were received from Brett Courcier. He personally used this type seat and is very satisfied.
My name is Brett Courcier. I live in Fremont Nebraska. I own a 1946 Chevy pickup street rod. I wanted to take a few pictures of how my seat fit in my truck. I was trying to find a seat for my truck. I found a Plymouth Caravan minivan rear seat. It fit great. I cut off the latching pieces that go in the minivan floor and welded on a piece of 2″ square tubing to the front legs and a piece of 1″ square tubing to the rear legs. The pictures show them. My upholsterer added lumbar support to the lower back area and also added 2″ in heigth to the back of the seat. The seat comes with three seat belts and folds forward from the back of the cab. We added a full length pouch across the back of the cab for storage. I hope the pictures show enough for you. If you have any questions please contact me.
402-727-7127 or e-mail email@example.com
We just had an email showing another excellent seat for a 1939-46 Chevy / GMC cab. This photo is of a rear seat cushion from a 1990 Ford mini van. Nice fit. This person found a top of the line leather seat in a local salvage yard. A good cleaning made it a very nice inexpensive seat that fit really well!
The Chevrolet and GMC left commercial taillight used during 1947-1953 is an excellent example of GM’s conservative thinking towards trucks. The number one purpose for trucks was work! Therefore, if a part had been very successful on a prior body design, it just might be adapted later as a part in some new styling. Savings were in production costs and tooling. The results were still a good practical part for a working vehicle.
This type of thinking it shown in the Advance Design 1947-1953 pickup taillights. The same light assembly had not only been in use on trucks since 1940 but the red lens and chrome bezel was first used in all taillights on the 1937-38 Chevrolet passenger cars.
With the introduction of the new 1947 body style, this same six volt light continued to be used. It was now turned 180 degrees, so that the clear license light lens was at the bottom, and did not shine upward as in prior years. This allowed for a smaller taillight bracket with low mounted license plate. On earlier models the high positioned license caught the wind. This plus the use of trucks on rough terrain often caused bracket failure. With the left light illuminating the license plate, the optional right taillight did not have or need this lens opening.
Because the same lens was used on the 180 degree reversed taillight in 1947-1953, the red lens letters were now upside down. This was not a problem to GM as trucks were for utility purposes. Changing the lens tooling just to make the cast letters show upright was not a consideration. The red lens sold by authorized Chevrolet or GMC dealers normally had STOPRAY block letters at the top and either GUIDE letters in script or “STIMSONITE” in block letters at the bottom. In 1949 GM changed the red lens from glass to plastic. This thinner material reduced overall weight and gave a brighter red when light passed through. The various aftermarket lens manufacturers also followed GM’s procedure. Even their lens lettering is reversed when placed on the 1947-53 trucks. It appears they also designed this lens with the 1937-1938 car in mind.
The light on the pickup and larger truck has a rectangle shape with dimensions 4 inch high x 2 1/2 inch wide. An authentic 1940-1953 GM light bucket will have the block letters GUIDE-MADE IN USA stamped on the back. These letters are not visible when attached to the factory taillight bracket. In 1947-1953 the 1/4 inch block letters STOPRAY were stamped in the top of the light bucket. These letters, prior to 1947, had been stamped in the area at the rear of the license lens on the opposite end when the bucket was reversed. In this way “STOPRAY” is always seen on the top in this series of taillight. The running light bulb (illuminating both the license and red lens) is three candle power. The stop light bulb, positioned behind the center of the lens, is 21 candle power. The bezel was chrome over the black bucket until copper shortages occurred in 1952-1953 due to the Korean War. The bezel then became black.
One minor change in this design over its early years was the reversing of a very small water drain hole in the lens retaining bezel. Engineers knew this water escape hole would be needed for drying and to drain moisture from within the bucket as the cork bezel gasket began to deteriorate within several years. This drain hole was centered in the bottom of the original light bezel; however, between 1947-1953 when the light was reversed, the bottom drain went to the lower right. This was due to an internal securing bracket welded the middle of the bezel and preventing there being a place for a center drain hole.
This taillight as used on pickup and larger trucks is mostly unprotected from the elements when located beside or under the bed. Tests quickly showed that some type of seal would be necessary in the hole where the two light wires from the bulb exited the taillight. As a modern rubber seal had not been perfected, GM skillfully came up with a solution. An approximately 2 ft. long, 5/16 inch diameter cloth woven black lacquered tube was inserted one inch into the bucket taillight wire hole. The inside end was flattened on the two wires with a heavy metal staple. This prevented the loom from being removed, protected the wires, and prevented water from entering the housing.
With the total redesign of the step bed in 1954, the six volt taillights were also changed. They became round four inch diameter units with one light bulb having two filaments of three and twenty one candle power. The lens retaining bezel was chrome plated on the more deluxe truck, painted black like the bucket on the standard models. The clear license lens was in the bottom of this bucket to illuminate the plate below. With the optional rear bumper on pickups, the license plate moved to the middle of the truck and the taillight did not have the lower lens window. As before, the right light was an option.
The 1947-55 taillights on the panel truck, suburban, and canopy express (single unit bodies) had no similarity to those on the pickup and big trucks. On panel trucks a single light was placed near the center of the left “barn door”. The lens retaining bezel was chrome with dimensions of 3 inch high by 4 1/2 inches wide. A decorative stainless two inch wide strip on top of the housing has the stamped letters GUIDE R17 T. A single socket in the housing holds a double filament bulb of 3 and 21 candle power. The license plate bracket is secured to the rear of the bucket and allows illumination of the tag below the light. During these Advance Design years, this panel truck lens and chrome bezel were also used on the rear fender of the Harley Davidson motorcycle.
The canopy express and suburban bodies also displayed a single taillight with suspended lower license. It was attached to a cast metal swing bracket on the center of the tailgate. This bracket plus a special vertical connecting rod made up an ingenious design. When the tailgate was opened to its horizontal position, the taillight and license would swing 90 degrees so that it could still be seen by the following traffic. This round taillight was normally black with a 4 3/4 inch diameter chrome lens retaining bezel. Inside are two sockets holding individual bulbs of 3 and 21 candle power. Block letters on top state GUIDCOLITE STANDARD. To save costs GM adapted this light from a prior application. It had been the GMC pickup taillight from the late 30’s through 1946. During these Advance Design truck years the light was also found on General Motors station wagons through 1952.
As the 1950’s progressed, there were increasing requests for a right tail light. This was a GM dealer installed option to be placed on new or pre-owned vehicles. On pickups it was easy! The option included a right side light and bracket closely matching the standard left assembly.
Adding a turn single option today 1947-1955 single unit body created problems for GM designers. Neither the single factory taillight on the double door or the center unit on the tail gate were in a good position to be matched with a second live assembly. GM solved this by offering a turn signal kit containing two matched taillights. These were dealer installed beside the vehicle belt line near the doors and above the edge of the tailgate. These small bullet shaped lights were actually from a 1939 Chevrolet passenger car. It appears GM dusted off the ten year old car taillight tooling and kept expenses on this option to a minimum. The letters “DURAY” are stamped in the top of the painted housing. The chrome bezel retains a 2 5/8 inch diameter red glass lens. Due to a small water drain hole, there is a right and left on these turn signal lights.
NOTE: It is interesting that both the pickup truck and the tailgate lights, each developed during the late 1930’s, continued with separate bulbs and sockets for each filament. The door mounted oval panel truck light, introduced in mid 1947, was provided with a more modern double filament bulb in one socket.
A redesigned parklight assembly was started with the introduction of the 1947 GMC advanced body style. It was placed in the front fender 3-1/2 inches below the headlight ring. A 2-5/8 inch diameter bezel held a domed glass lens to its housing by two barrel screws.
The unit was not meant to be a combination turn signal and parklight assembly and held a 3 candle power single filament 6 volt bulb. As with other car and truck parklights prior to 1968, it did not operate when the headlights were on.
This round lens and chrome ring soon found other uses. They were placed on the parklights of Chevrolets new Corvette sportscar between 1953-1962! The ring also held a different lens to the rear of certain GM cars when they had the optional backup light assembly.
During 1952-1953, GMC used an enlarged parklight assembly only different than the 1947-51 unit in size. Dimensions were increased to 3 inches diameter to give more light area. It fit in the same front fender location and the securing ring was now painted white as was most other 1952-53 GMC trim during the Korean War shortages.
This larger glass was shared with several larger GM cars as their parklight lens. The same rings, however, were chromed. These chrome rings were also used to hold a different clear lens on several GM cars for their back up lights.
Though items were shared between GMC and Chevrolet trucks between 1936 and 1946, General Motors made sure many parts remained very different during the early years the GMC preferred very few things to be similar to Chevrolet. Their customers needed to see an almost stand-alone truck with the higher price of the GMC.
One very obvious difference is the change in tail lights. There is no comparison to Chevrolet. The massive GMC stamped one piece steel bracket combined with a redesigned 5-inch tail light makes the pair a “one-of-a-kind”. They do not interchange with Chevrolet during those year.
It was not until the new body style in mid 1947 that the two brands shared tail lights. When the larger GMC’s 5-inch light was discontinued on trucks in 1947, Chevrolet introduced it on their 1949 through 1952 station wagons and early GMC buses. It was placed in the center of the gate and was the only factory light on the vehicle.
Even though 1936-1946 taillight was used for so many years, it is becoming very difficult to find. Most GMC pickup restorers use the reproduced Chevrolet rectangular design and only a few GMC perfectionists are aware that there is a difference.
A shop in the US is attempting to remake this bracket; however, if this happens the tail light will be almost as big of a project to find. It is not being reproduced.
Hint: This tail light also was used on Chevrolet, Buick Oldsmobile Station Wagon tail gates from about 1949 through 1952. Therefore you will see more lights than GMC brackets at swap meets. See Photos
During the mid 1960’s, most still considered pickups work vehicles. The manufacturer designed them as haulers and few people owned them as their only family vehicle. However, a slight change was beginning with truck buyers as Americans began to have more disposable income. GM and other truck producers were aware that extras on work vehicles were finding more buyers. Each year additional pickups with deluxe equipment were ordered.
This 1965 GMC 1/2 ton is an example of this trend. Though it obviously had been a work truck, it’s optional deluxe features still remain intact. Looking at the trim shows how GMC designers were careful in adding expensive trim.
To keep cost down they placed chrome on the hub caps and grill of their base model pickup. The stainless windshield trim is identical to that placed on the Chevrolet deluxe cabs. The long anodized aluminum side trim is also Chevrolet. One exception: GMC did not use the narrow shorter side trim as found on Chevrolet fleetsides that ran parallel to this longer piece. See photo comparisons.
Most aluminum cab trim is very basic in design. Straight pieces butted together kept GMC’s cost low. Only the chrome plated die cast emblem with the word “Custom” shows extra design effort.
The curved door window trim did require extra tooling but was made of anodized aluminum. Note this aluminum window trim as it runs parallel a few inches from the windshield stainless. The use of two different materials on trim so close is very unusual.
The 1967 Chevrolet and GMC trucks are noted for numerous one year only features. As the year progressed, engineers made several changes they felt were an improvement over this first year design.
For reasons unknown, dash knobs were redesigned. The following pictures show the correct 1967standard knobs with 1.23 inch diameter serrated edges. Compare these with the 1968-72 knobs having 1.4 inch diameter and smooth edges. Pictured here are several of the deluxe style having the center silver paint. Most did not have this silver addition.
With increased prosperity in the USA during the 1960’s the demand for more extras on cars and trucks was high. Manufacturers followed this trend with additional features, at least on their top of the line models.
GMC followed this movement even though their product was mostly for work related duties. While sharing much sheet metal with Chevrolet, they certainly did not want to look like their competitor so GMC designers made a point of adding no deluxe features to the new ‘Custom’ truck that would relate to Chevrolet.
What must have been a limited budget is reflected by the inexpensive trim on their new custom cab. The post behind the doors uses three pieces of straight anodized aluminum butted together to fill the space.
What looks like an amateur creation was truly a factory design. It almost appears they needed paint divided strips for their two-tone paint option! A more expensive piece is the curved side window trim with the unusual groove to fit into the door lines.
For their custom cab GMC chromed their pre existing white grill, V-6 hood side emblems, bumpers, and hub caps. Thus, their design and manufacturing costs were lessened. Even the stainless windshield trim was already available from the Chevrolet division. A new small chrome Custom emblem on the door post is an exclusive GMC only part. (This die cast emblem was also used on the rare deluxe model GMC Suburban.)
The remaining GMC ‘Custom’ feature appears to be the paint scheme when two-tone colors were ordered. Here designers seemed to have gone to excess. No copying Chevrolet here! There must have been a 20 minute meeting on the telephone in 1964 to decide which color went on which metal body panel.
The accompanying photos are from a 1964-66 GMC Custom ½ ton pickup that was seen parked along the street. The owner was not available for comment.
The wear on the original paint and trim give no doubt that it was an untouched factory GMC. Its pure condition deserved ‘a second take’ and the following pictures were a result.
Note: Even on the Custom GMC pickup, the large back cab window was optional. Many did not want the extra sun on their neck or in the cab during hot summer days. Therefore, this deluxe cab was ordered with the small rear glass.
During the early 1960’s GM’s majority of truck buyers chose the base truck with few dealer installed options. It was ending an era of very limited disposable income among the average US citizen.
General Motors saw the trend toward more extras on trucks and began to offer visual extras such as two tone paint, side trim, and upgraded interiors.
Though there were limited takers, both Chevrolet and GMC offered full length stainless steel side trim during 1960-61. Note: Cab and front fender trim are the same on both makes. It is the fleetside bed trim that is a different length. On the Chevrolet, the rear “C” side piece requires this trim to be shorter than the GMC. See images below.
Between 1954 and 1959 the dash cluster of GMC trucks were given a circular opening for a dealer installed clock or tachometer. These trucks left the factory with a blank-out plate to fill this opening. With most GMC’s this plate always remained in place as an option was rarely added.
The enclosed photo shows both plates used during the period. We are requesting help to identify the years each were used. Contact us for your opinion at www.oldchevytrucks.com
With the new Fleetside bed design in 1958 the Chevrolets placed a chrome emblem on the bed side with the word “Fleetside”. However, GMC referred to this new bed as a “Wideside” to not copy Chevrolet. A Wideside emblem was never created, thus the GMC bedsides are without letters. (The horizontal bedside trim is a 1959 option).
During the mid 1950’s, V-8 engines began to gain popularity. Many became an option in full size cars and trucks that normally were provided with a six cylinder. When this occurred, most vehicles were given a body emblem advertising that the larger power plant was under the hood.
1955-1957 (above left) | 1958-1959 (above right)
GMC trucks were no exception. During the 1955-59 body style, two different shapes of V-8 emblems were used. Both die cast designs were attached to the front fender below the GMC letters. The above picture shows these V-8 emblems and the different GMC letters that appeared above them. If the truck came with a six cylinder, only the letter emblem was used on the fender. Today, as many older trucks are given modern V-8 engines, the original V-8 emblems have become almost impossible to find. The demand for these rare emblems has far exceeded their availability.
These are some very rare photos. It is quite unusual to find 1947-1953 Chevrolet and GMC 1/2 ton bare frames together. Here, you can cmpare the differences in the front cross members.
As the GMC six cylinder is a few inches longer than the Chevrolet, engineers designed two different front engine cross members. In building the truck frame for the assembly line a different cross member was added depending if it was to be in a Chevrolet or GMC factory.
This is why re-builders of GM trucks today develop immediate problems when they exchange 6 cylinder engines between the Chevrolet and GMC. The two makes may look about the same in any year, however the power plant causes changes not only in the frame’s front cross members as well as sheet metal in this immediate area.
GMC bumper guards during these years were standard equipment and stamped from the same heavy gauge metal as the bumper (a different style and lighter gauge metal were dealer accessories on Chevrolet light trucks).
A slight change in design was made at the end of the 1956 year. A more decorative pointed end was given the guards during 1957 through 1959.
These chrome hood ornaments were exclusively tooled for GMC trucks and have no similarity to the Chevrolet style. They are made up of three attached die cast pieces to create the finished product. Their slim base secures to the center of the hood divider strip.
These were dealer installed GMC accessories. As trucks at that time were mostly for work responsibilities, few owners had an interest in appearance options. Thus, these hood ornaments were rarely seen on trucks when new. Locating new or restorable unit 50 years later is almost an impossibility
By 1954, the Korean War shortages were history. More trim and chrome plating began to show up in trucks and cars. The Chevrolet and GMC truck divisions both introduced a deluxe model for their pickups during mid-year 1954. Hopes were to appeal to the emerging buyers with more disposable income.
The deluxe model of these two trucks shared most of the same sheet metal, however special unique items kept each individual! One of these exclusive items was used only on the top of the line GMC pickup. This was the bed-roll reflector. It was never placed on Chevrolets or the basic GMC pickup.
In today’s world this extra is almost impossible to locate. Not only was it on the deluxe GMC’s but few of these top of the line models found buyers. Most still thought of trucks as workers and ordered the basic vehicle. This reflector is on the very end of the bed roll and it is exposed to being damaged while backing.
To save tooling costs, GMC designers borrowed the red reflector lens from the 1953 Buick taillight. Unfortunately, the stainless ring (riveted to the bed roll) is exclusive only to the rare deluxe GMC pickup.
During the Advance Design years, 1947-55, Chevrolet and GMC each changed their grille designs twice. GMC made the change at the end of the second year and Chevrolet made the change at the end of the seventh year.
Possibly to save tooling cost GMC, not Chevrolet, always used the same grille on all truck sizes in any one year. As Chevy used a similar but slightly larger grill on their 1 1/2 and 2 ton. GMC did not change the size on trucks between 1/2 and 2 tons.
In 1947-48 GMC used a three bar heavy gauge chrome steel grille. Actually, it was for the heavy weight for the 2 tons but fit in the 1/2 ton by using a smaller grill surround.
The big grille change for GMC was in 1949 when it was made as a four bar design. To the non truck enthusiast, it looked somewhat like the earlier years which is probably what GMC designers planned.
Current GMC grille reproductions are often sold as 1947=55. Actually they are the four bar type for 1949-55. The 1947-48 GMC owners get a surprise due to the modifications needed to fit the later reproduction grille into their early housing!
Between 1947-1953 the Chevrolet 1/2, 3/4, and 1 ton grilles were made from the same tooling. However, the paint colors and some with chrome plating made a difference. For the perfectionist, the following data will help you build a correct grille during your restoration.
The standard grille has inner and outer bars the body color. Horizontally, a pin stripe is run on the edge of the five outer bars. It is the same color as the cab stripe.
1949 to Mid 1951
Standard grillexs have outer bars the body color without a horizontal stripe. The inner back splash bars are Waldorf white.
Mid 1951-1953 (Korean War Years)
Outer bars on standard grilles are the body color as prior years. The back splash color changes to Thistle Gray (light gray) to match the newly introduced gray hub caps and bumpers due to Korean War shortages.
The deluxe grill has the five outer bars in chrome. The four inner bars remain the cab color.
Chrome grills for these years are plated on the outer bars. The back splash color remains the same white as the painted grill.
Mid 1951- 1953
Chrome grill bars were not available due to Korean War copper shortages. Thus, these grills are the same on deluxe and standard trucks.
Vertical Bar Supports
1947-1953 Both Painted and Chrome Grilles
The two outer vertical bars touch the fenders and are therefore their color. Unfortunately, the reproduction grilles are easily recognized at shows because the owners have not often painted their outer bars fender color! The three smaller inner vertical bars are semi-flat black. This prevents them from being easily seen when viewing the vehicle at a distance.
NOTE: We see no reference to chrome outer bars being offered during the 1947-53 Chevrolet Advanced Design years.
Used only the first 1 1/2 years into this body style, these GMC grilles stand out for their different shape and very heavy duty construction. Because of it’s weight this assembly, it sets on the frame and is given extra support by a pair of steel rods extended at an angle to the frame rail. See photo.
The grille has three horizontal bars and uses a heavier gauge metal than the four bar grille introduced in 1949. This same unit is found during 1947 and 1948 in all 1/2 ton through 2 ton GMC trucks.
On these early 1/2, 3/4, and 1 ton trucks the splash apron from the grill to the bumper is even different. The front bumper is the most unusual. It is rounded much like an automobile and has three bumper bolts on each side. They all have the small grill guard on the 1/2 and 3/4 ton.
Some suppliers of 1947 – Early 1955 bumpers and grilles state they are all the same. But, they are not. The 1947-1948 stands alone!
1947-1948 “3” Bar (above)
Note the 3 bumper bolts. The center secures the front splash apron and securing braces. The other two are used by the dealers to attach GMC accessory larger grille guards to the bumper.
The big news for GMC in 1936 was the introduction of their first 1/2 ton pickup. Though GMC now shared cabs with Chevrolet trucks, the visual exterior differences were mostly noticeable in front of the hood.
The GMC grill was totally redesigned and did not resemble the Chevrolet truck. This unique grill was modified little between 1936 through 1938 but the top grill ornament was changed with each of these years.
Watch for these ornaments at swap meets, antique shops, and older vehicle trade shows. They are extremely rare! Even locating the real thing for the following photos was very difficult.
The first year for the newly designed GMC 1/2 ton (cab shared with Chevrolet trucks) and the last year for the exterior radiator cap. This example of flowing artwork rivals even nicer automobiles of that year.
The hood must be raised to reach the hidden radiator cap but a fixed die cast logo (similar to 1936) remains the focal point at the top of the grill.
GMC extends the smooth front hood hold down upward several inches and eliminates the die cast letters. This chrome extension (not like Chevrolet) can be just as rare as the early style. Once off the truck at a salvage yard, it soon becomes mixed with scrap iron because of no identifying GMC letters.
Many of the tech articles on this web site emphasis’s the subtle ways that truck parts were made economically by GM. Truck often received Chevrolet car items that were used the year before. Sometimes even other GM brands sent their older items to be placed on assembly line trucks.
Of all the ways GM saved money on truck parts, none is more unique than the savings on 1/2 ton hub caps. Chevrolet pickups used the same baby moon style hub cap from 1940 through 1955. The skins and basis are the same. A relative inexpensive addition was simply changing the lettering or emblems on the outer brass skin. They required a change in tooling, not expensive for a company the size of the Chevrolet Motor Division. The stamping department just kept making the same base and skins. The skin surface stamping changed as was required by the design department each year.
Check the following pictures. The base hub caps are all the same. Some of the car hub caps are the same as the trucks. Even GMC trucks decided to use these caps between 1947-55. After all, just placing the three GMC letters on the skin added much savings to the company’s bottom line.
1940 Chevrolet 1/2, 3/4 ton and car (above)
1941-1946 1/2 ton, 1941- 1945 3/4 ton, and 1942 -1948 car (above)
Companies outside the Chevrolet Motor Division have always produced replacement parts for the aftermarket industry. Manufacturers begin reproducing non-original parts very soon after a new vehicle is introduced.
A problem occurs on decorative trim such as hub caps. Here, Chevrolet (and other manufacturers), display their logo to attract positive attention. To reproduce a Chevrolet hub cap, non-GM companies have at times altered the bow tie logo. In this way, they have avoided legal action by GM and market a hub cap that was close to the original. Their hope is that most people would not notice the small changes. These caps were usually produced in the 1930’s ‘ 40’s and marketed through auto parts stores or by mail order.
In today’s world, these caps have become very rare as few collectors use them on their vehicles. GM has now given approval for reproducing these obsolete correct logo caps and most collectors want the real thing. The few remaining ‘counterfeit’ caps have a place on your garage wall with their unique history.
The 1939-1940 Chevrolet and GMC grilles may look the same when they are seen separately, however they are not! By sharing fenders, hood top, headlight stands, etc. , the grilles overall dimensions had to be the same. To keep each marquee individual, GM made the grilles different. When the two are compared side by side, what a difference!
Though at quick glance, the GMC grilles of these two years may seem the same, however, look close. Changes at the top show slight differences. The die cast assembly at the top of the 1937 grille gives the impression that the vertical grille bars extend through the emblem. They don’t! It’s an illusion and is die cast. The hood ornament above repeats the GMC letters.
The 1938 doesn’t have the upper die cast vertical bars. They even eliminated the GMC letters on the hood ornament.
All these emblems are extremely rare. If they have the GMC letters they usually go in a hobbyist collection. If they don’t have the GMC letters, most people don’t know what they are once separated from the truck in a salvage yard and they go to the iron pile.
The placement of rear axle bumpers by GM on 1/2 tons proved to be an important feature. Owners can often load cargo over recommended weights, their shock absorbers may lose their resistance, and there is the existence of uneven road surfaces. All this can make axle bumpers very important.
During the hauling of freight, these bumpers occasionally stop metal to metal contact between the frame rails and the axle housing. GM placed them just above the rear axle. See photos.
1947-1953 1/2 ton (above)
In 1954 GM increased the depth of the 1/2 ton pickup bed from 15″ to 18″. To do this they lowered the frame rail arch above the rear axle. This shortage of space caused the bumper to be placed at the side of the frame but still above the axle.
Leaf spring width on 1/2 ton pickups remained at 1 3/4 inches until the introduction of the two inch width on the Task Force 1/2 tons in mid 1955. The early narrow springs worked well considering the engine horsepower and weight limitations of the 1/2 tons. The two inch springs became standard equipment on the rear of the 3/4 ton in 1946 but their fronts still remained the smaller size. This is because the increased weight carrying ability of the 3/4 ton is mostly felt in the rear. Only 1 ton and heavier were totally without the 1 3/4 inch springs.
With the abuse given pickups in the early days (poor roads, overloading, and almost no lubrication), the springs have held up well. Most mid 1955 and older 1/2 tons continue to operate with their tired original narrow springs.
In today’s world a new variable exists that puts even more demands on these small springs. It is the increased horsepower of later model engines. No problem if these trucks, converted to more powerful engines, are driven as if they still have their original six cylinder. However, problems arise with jack rabbit starts with or with a heavy freight load. Most of these Advance Design 1/2 ton’s with transplanted V-8’s have had their original closed drive shafts replaced with open systems. The replacement axle housings are clamped to the 1 3/4 inch rear springs. When heavy acceleration is forced on these modified trucks, the axle housings try to rotate due to the extra torque. Much of this movement is held in check by these narrow springs. They just weren’t designed for this. Breakage and permanent bending can occur.
Don’t push your 1 3/4 inch rear leaf springs beyond their limits. If you demand fast acceleration with your V-8 1/2 ton, convert to later model 2″ or 2 1/2″ springs. Check specialized suppliers, including Jim Carters Truck Parts (part # HP580), for add-on kits.
It was during these years that General Motors began offering more style to their pickup truck line. Though most still considered a truck as a work vehicle, a growing segment of pickup buyers were being strongly influenced by trim and accessories that even rivaled many automobiles.
For the first time on GM fleetside pickups, decorative trim became available on the tailgate of their middle and upper level models. Even on the basic gate that had no trim, the stamped letters were given a contrasting color. During all of 1967-1972, the middle and more deluxe series gates carried three upper strips making one line running the width of the gate. These three strips were the only tailgate trim offered for 1967-1968. During 1969-1972, an additional horizontal strip (66 3/4′ long) was attached to the lower gate edge but only on the middle series fleetsides.
It was on the top of the line 1969-1972 pickup that Chevrolet went all out in tailgate appearance. On the 1969-70 CST and 1971-1972 Cheyenne, the lower trim strip was replaced with a very attractive wood grained horizontal band at the center. Though it covered the basic Chevrolet and GMC stamped gate letters, the band carried its own chrome die cast letters over the wood (vinyl) decal.
The following photos show both the three styles of trim on the 1967-1972 fleetsides. Note the lower narrow strip is not placed on the gate with the wood band. Tail light rings or bezels are designed to harmonize with the tailgate trim. The 1967-1968 CST light trim is different than the later design.
The main cross grill stamping making up the 1967-1972 GMC grilles may at first appear the same but they definitely are not.
The more noticeable difference is the large GMC letters stamped in the center of the 1967 grille (one year only). Therefore, these three letters are not placed on the hood front as during 1968-1972. Between 1967-1970, the vertical center bar (3″ x 10″) is slightly raised above the outer edges.
This vertical center bar on the 1971-1972 GMC grille is slightly depressed between its outer edges. This depression is painted satin black. At a distance, it gives the appearance of a split grille with two equal halves.
During the first year of this new body design GMC’s top of the line was referred to as the “Super Custom”. An unusual piece of chrome die cast trim was added to this model in the center of the front fender this year. (not on Chevrolet) It is identifiable in the GMC Master Parts Book as: Group# 10.095, Part# 3903748/
It is now very difficult to find and probably will never be reproduced.
NOTE: This factory drawing shows the now rare full wheel covers, on the Super Custom.
The straight axle ½ ton GM pickups (1959 and older) were built tough! They served their purpose as the best in work vehicles for over 30 years. Other than an occasional kingpin replacement, they were almost ‘bullet proof’.
In today’s world, the reasons for owning an older truck, has generally changed. Most have been retired from work responsibilities and have become ‘fun trucks’ driven with care on smooth streets. Hauling merchandise is far down the list of their use.
The resulting demand for a smoother ride and better braking is the reason for many suspension options available from supply houses. For those willing to compromise on originality for an easier ride, one of the most proven and less expensive upgrades is the front suspension of the AMC Pacer. The price is right and the results are excellent. This coil spring rack and pinion front suspension assembly gives passenger steering and ride qualities.
A specialized adapter plate (available from the catalog on this web site, HP127) allows for the connection to your ½ ton truck. Instructions explain parts to remove from the Pacer assembly before the plate is welded in place. The total assembly is then bolted to the truck front cross member. No cutting on your truck! You can even trim the Pacer coil springs to get a lowered level on the total vehicle.
The adapter plate is not expensive. The main project is locating a good Pacer front suspension. This AMC vehicle was produced between 1975 and about 1982. The later years even had disc brakes.
Mechanical components on trucks were usually kept for many years by GM. Unless an improvement was needed, there was no need to change a proven design.
An excellent example of this is the rear ½ ton axle bumper. The design was used from 1929 through 1946 on Chevrolet and GMC ½ tons. A rubber bumper is held down on the rear axle housing by a metal cover with two ears. These ears are firmly secured by the two u-bolts that connect the leaf spring to the round axle housing. If the truck is overloaded or the shock absorbers are worn, the rubber bumper prevents metal to metal contact between the axle and frame rail.
Two of the attached photos show an original used retainer with bumper in place. The black bumper (now reproduced) is how the rubber part looks when new.
Suburbans ‘ people haulers on a 1/2 ton truck chassis. Not designed for truck freight, the successful Suburban was created to move people. They quickly gained popularity among the military, as crew haulers for companies, and for small rural school buses.
By the 1960’s, GM began to expand their Suburban market to attract families. To many this would be a great heavy-duty family car. A more deluxe Suburban model was introduced. The exterior trim and well appointed interior defiantly showed this model was not for commercial use.
These pictures of a 1962 top of the line GMC Suburban show the unique trim that was placed on this model. It is for GMC only ‘ not Chevrolet. Though Chevrolet shared the same body and some chassis parts; trim, interior, and colors were different so each brand could be individual.
Look closely and see how the GMC brand kept their cost of side trim to a minimum. Other than the curves around the front door windows, straight pieces of aluminum trim make up the package. The more obvious economy steps are on the rear quarter panel. Note vertical and horizontal trim strips simply butt together. They also act as paint divider strips for the two-tone paint combination of the GMC. The die cast chrome ‘custom’ emblem in the same as on the GMC pickup.
This is an excellent example of a very original GMC Suburban interior. The woven green seat material is as it was 40 years ago. The right jump seat swings up and forward to gain access to the rear. Note how the middle seat is shorter so that the passengers can walk to the rear.
Today, even finding a 1960-1966 GMC Suburban is rare but locating one with this deluxe custom package is almost impossible.
With the introduction of GM’s new truck body design in mid 1947, a delivered package became available on both Chevrolet and GMC. World War II was in the past, employment was high, and many American truck buyers were willing to pay a little extra for more options on their new vehicle purchase.
GM’s sales department recognized this as an opportunity to fill a need and sell a few more vehicles. A deluxe truck would look good in a dealer’s showroom and the market existed for nicer trucks.
Prior to this new body style, GM truck cabs were the same from the factory. Dealers installed the few extras provided by the manufacturer.
The new deluxe cab for the Advance Design trucks cost GM little additional in comparison to the standard design. Most items were already extra cost options or standard parts that were modified. The deluxe package included the following:
Five Window Cab. This was the largest expense. The Two corner windows required a different roof panel to be attached to the lower half of the body. The center rear window was the same.
Chrome Grill Bars. The option was also available for the base pickup. It was created by polishing and plating the five painted bars. This came only on 1/2, 3/4, and 1 ton.
Stainless Steel Door Window Trim. The factory dies that formed the painted standard trim could also stamp stainless steel. The outer was polished. The inner was left a satin finish to reduce glare from the sun.
Stainless Steel Windshield Trim. This was only on the deluxe cabs. Painted trim was not on the base cab. Therefore, GM had to create dies to produce it, give a high polish, and provide a modified windshield trim was still painted on deluxe models.
Right Inside Sunvisor. This was already a dealer accessory on the standard cab. The attaching holes were even punched on all cabs and covered with the non-punched headliner cardboard.
Left Arm Rest. A dealer accessory on the base cab, therefore holes are stamped in both doors at the factory. They are hidden with the cardboard upholstery panel on standard cabs. No extra tooling here!
By 1951 material shortages due to the Korean War conflict were effecting the automotive industry. Shortages of at least copper and stainless greatly raised raw material prices. To prevent a shut down of assembly lines due to no product, GM discontinued the deluxe option.
From late 1951 through 1953, the Chevrolet and GMC deluxe cab had no bright work. It retained the sunvisor, left arm rest, and corner windows, however most chrome and stainless were gone. It was not until 1954 that the trim was retuned to the deluxe cab.
The enclosed photos are of a 1951 Chevrolet 1/2 ton deluxe cab owned by David Bosley of Felton, PA. His grandfather purchased the truck new so David recently restored it just the way it was bought in 1951. Even the bed boards are painted! The door vent shades are a non-GM option but available in the early years. The other trim items are either part of the deluxe package or are options provided by the Chevrolet dealer.
When looking closely at the black 1954 Chevrolet speedometer face, a small 1/8 inch diameter round hole will be noticed at the top and bottom.
Owners of 1954 trucks will always be acquainted with the top hole. This emits red light to notify the driver that the high beams are on.
Most are not even aware of the existence of this lower hole. Look closely. It’s always on the 1954! It is placed there to emit a flashing green light when the optional turn signals are added. Prior to this model, the GM trucks add-on turn signal head was clamped to the steering column. With the turn signal on, a small light would blink in the head.
In 1954, the optional turn signals became ‘built-in’ the column below the steering wheel. The blinker light became a part of the dash like later vehicles.
When the factory or the dealer added optional 1954 turn signals, the little hole with green tape inside was ready for the new dash bulb. This one flasher light would blink if the signal was to the right or left.
On first glance, most people assume that both Chevy and GMC gauge clusters are fully interchangeable and are the same except for perhaps the minor difference with Chevy oil gauges topping out at 30 psi versus GMC gauges maxing out at 60 psi. But that’s quite a bit short of what the actual differences were originally! There are actually no less than five distinct differences in the same year gauge clusters when taken from same size trucks. Below you will see two examples of late 1951 to 1953 gauge clusters; one on the left from a Chevy truck, and the one on the right from a GMC truck. Before you start jumping up and down about the tan background brown letter gauges in 1951, realize that the gauge clusters changed in late 1951 and then stayed brown background cream letters up through 1953. The first and most obvious difference is the oil gauge, but upon closer inspection you’ll find twelve distinct differences between them; six on each gauge cluster.
GMC oil gauge reads 60 psi while the Chevy oil gauge tops out at 30 psi
GMC used an Ampere gauge showing 50- | +50 where Chevy used a C | D Charge/Discharge style gauge
The label under the electrical gauge on Chevy clusters says simply “BATTERY” while on the GMC it says “AMPERES”
GMC temperature gauges maxed out at 220F where Chevy temperature gauges stop at 212F until 1953. In 1953 Chevrolet matched GMC with 220F
The GMC fuel gauge was used for both big and small trucks, so it reads “FUEL” where the Chevy gauge reads “GASOLINE” since there were no Chevy diesel trucks at that time
The Chevy gauges all have longer 2/3rds way needles than the GMC gauges with half-way needles
So the next time you’re shopping for gauges, these subtle differences may help you to better understand what you need whether you are driving a Chevy or a GMC.
One of the numerous differences in the new 1947 Advance Design trucks is the different position of the mounting tabs on the speedometer. Reasons for doing this on both Chevrolet and GMC are as follows: with the introduction of this body style in mid-1947, both 3 and 4 speed transmissions were the floor shift design. However, in 1948 with the introduction of the 3 speed column shift transmission, the new shift linkage was now parallel and above the steering column. The distance between the two lower tabs on the speedometer case was widened from 4-3/4′ to 6′. This got the tabs away from the new shift linkage.
The person restoring a 1947 Chevrolet or GMC should be aware of this change. If he turns in his speedometer core to a re-builder on exchange, chances are good he will not receive a 1947 style in return. Few, if any, re-builders will notice this tab repositioning and will exchange from their stock!
In designing the panel truck, engineers realized that this vehicle must have a bumper for body protection. This bumper however, created a slight problem! It held the person loading freight further away from the vehicle cargo floor. He was required to lean further forward to reach merchandise.
To help solve this problem, GM modified the standard bumper to come closer to the middle of the body. The bumper was simply given a stamping at the manufacturer and the solution was achieved. Though it gave the worker only a few more inches, it helped increase his reach.
In today’s world, the indented panel truck rear bumper (1946 and older) has become difficult to find. Most panel trucks are restored with a bumper from a pickup truck. Few owners are even aware that this specially formed bumper existed.
The 1934-36 half ton Chevrolet truck body style always placed their 17′ spare in the right fender. Even the Chevrolet car normally used the right side when only one side mount was added.
In mid 1936, GMC entered the ½ ton market for the first time. This light truck shared most all sheet metal and chassis components with Chevrolet except for the engine, hub caps, grille and tailgate lettering.
One of the more visual differences between the 1936 Chevrolet and the new GMC 1/2 ton is the location of the side mount spare. The GMC is on the left, not the right as with Chevrolet. This was done with little expense as the mounting brackets will fit the right or left side.
Why did GMC place their spare on the opposite side? The answer 70 years later is not known. We only assume it kept the two marques more individual with no extra expense.
Due to the abuse given trucks when they once considered only for work, many body components today are damaged beyond repair. During the restoration of your 1947-1955, if you would rather not use a running board splash apron from a parts supplier, there is an alternative.
Locate a piece of new flat metal the correct gauge and size of your original splash apron. Gradually begin curving the sheet by bending it over a six inch diameter pipe. Secure the pipe in a table vise or equivalent. This will result in the curve you need without unsightly bends on the surface.
The next step takes more patience but you can be successful. Borrow or otherwise locate a small metal break and bend the original angle on the perimeter. You will need to trim the edges to the approximately 3/4″‘ width as original.
Some hand bending where the apron fits against the ridge of the rear fenders will be necessary. This can require some pliers to begin the rounding. Use a round hedge hammer to continue the curving process. Take your time here!
Slight mistakes on the edges will not show from the outside of the pickup. Making your own running board splash apron is especially a good consideration on a 1 ton pickup. These very long aprons are not available from aftermarket suppliers.
This Tech Tip comes from Richard Pasauage of Wilks Barrie, PA. He personally made his 1950 Chevrolet 1 ton running board splash aprons.
The differences found on the cab during the beginning of the Advance Design years are subtle, yet on close study soon become quite evident. It probably exists on all vehicles when a body style is first introduced. Lab tests on a vehicle tend to overlook a few problems that later surface when it is in the hands of the consumer. Thus engineers made various corrections on the 1948 cab leaving the first year of this series with several unique differences.
Beginning with the Advance Design trucks in mid 1947, the top of the body cowl directly below the rear of the hood is smooth. This is the space between the rubber hood lace and vertical firewall panel. GM soon discovered that in this area an error in design existed. During heavy rain all water that flowed past the hood lace could run forward and then down the firewall. This allowed water on important items such as the voltage regulator, fuse box, wiring, fresh air heater motor, the rubber grommets that held tubes, lines and the original cotton braided wires.
By mid 1948, an appropriate stamping change was made which remained through the end of the series in early 1955. This was a groove or trough running side to side in the top of the cowl. These troughs drain rain water down the cowl sides onto the recessed area by the hood hinges and protect the firewall components. Now 50 to 55 years later we are noticing a rust condition due to these water drain troughs. Seldom will a 1947 cab have major rust in these hood hinge indentations. The cabs between 1948 and 1955 will usually be showing rust out or at least much surface rust when stored outside for many years. There is only so long this recessed area can resist the regular attack of water runoff from the troughs before it begins to show deterioration.
No water troughs
Another very noticeable feature on only the 1947 Advance Design cab is the lack of a hump in the lower part of the dash above the steering column. On 1948-1955 cabs the hump is necessary to allow the three speed column shift lever to pass down to the shift box. During the developing stages of the Advance Design cab, after World War II, the 3-speed truck transmission with column shift did not exist. Both 3 and 4-speed transmissions were using the floor shift system and a column shift hump in the dash was not a consideration.
As the 1947 Advance Design trucks continued using the 3 and 4- speed transmissions of prior years, their park brake lever is also unchanged. It remains secured to the right side of the transmission and is a vertical hand pull lever. With the introduction of redesigned 3 and 4 speed transmissions in 1948 the park brake was activated by a foot pedal on the left side of the cab. This pedal was in 1/2 and 3/4 tons only. The 1 ton and larger continued with a hand pull lever design throughout the series.
The firewall on the 1947 cab is one of its most unique features. It is not only different from the other Advance Design years, but is an excellent example of changes that save production costs. Initially the firewall was a flat sheet of metal welded within the edges of the cowl, etc. To prevent possible flexing of this sheet, GM welded two vertical U-channels, 11/2 inch x 16-3/4 inch to the inside. These two channels are hid by the inside firewall pad and therefore are not normally seen by the owner. Close observation will show the channel spot weld dimples on the engine side of this firewall sheet.
This flat sheet type firewall differs from the other years. By 1948, the second year of this body style, a less expensive method was used. The welded vertical channels were discontinued and were substituted with stamped rounded ridges or stiffeners in the flat sheet. These could be made with one stamping while the necessary holes were also placed in the sheet at the same time.
NOTE: We are now discovering that the unique features on the 1947 cowls were carried over into the early 1948 suburban, panels, and the canopy express. As these large single unit bodies were much slower in sales, it was possible GM had an over supply of 1947 cowls at the particular assembly plant producing them. They continued to use these early cowls until supplies were used.