lighting

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 separated 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...

  Contrary to what almost all Chevrolet truck parts dealers list in their catalogs, the 1969-1972 headlight bezels were not alike. Though today all are reproduced in bright-anodized aluminum. This is actually only correct for 1971-1972. The 1969-1970 bezels were black stamped steel even on the most deluxe models. This color is necessary to blend with the two horizontal black...

  The cargo light above the rear window on the 1969-72 GM cab was a factory option and is mostly seen on the more deluxe trucks. This light is controlled from a switch beside the interior dome light and is wired so it will not operate while the truck is in the forward gear. This prevents the bright 21 cp...

For those on a quest for near unobtainable GM options, this one will provide years of searching. During the mid 1950's, backup lights began to show growing popularity and were occasionally seen on pickup trucks near each rear fender. The limited production 1955-56 Suburban was no exception but the location for its backup light was unusual. Their single center tailgate...

  The differences between these two series of tail lights is an excellent example of lowering costs during production. To keep competitive, manufacturers will always consider making products of equivalent quality, but at lower prices. In 1960-1966, GM, as well as several aftermarket companies, used a redesigned tail light lens and eliminated the need for the earlier metal bezel. The...

The 1955-59 Chevrolet and GMC originally came with a non-metal shield to direct light into the ignition switch to the key slot. This shield is almost always missing after fifty years. Most shrink after twenty years and fall from the switch. The accompanying photos show this snap-in shield in place. Even the die cast opening is notched on all switches...

  The rear fleetside fenders on the 1955 through 1966 are usually considered the same. The reproductions on both metal and fiberglass are listed in catalogs and related advertisements are shown as being identical on the right and identical on the left. Not true! GM modified this last year fender of the 1955-66 series with a stamped indention in 1966...

  To keep vehicles base price low, GM made many items dealer accessories. If the buyer required extras, the dealer was the installer. This created less complications on the assembly line when they were special ordered and added more income for dealerships. One exception is 1966. That year, the US Dept. of Transportation made it a requirement that all cars...

With the introduction of the Advance Design panel truck in mid 1947, it was soon evident that a serious safety hazard existed with a few companies, some night deliveries required the rear double doors to be open. This prevented the taillight from being seen! No doubt this caused some accidents particularly with a fast vehicle coming from behind, with dim...

  Beginning in 1951, the rear bumper became an option on both Chevrolet and GMC pickups. This required a change in the standard left tail light bracket. The tail light assembly was now unprotected without the bumper. GM created a new bracket design that brought the tail light slightly ahead of the rear edge of the stake pocket. In this...

The introduction of factory sealed beam headlights came to the automotive industry in 1940. It was then necessary to create park light assemblies. (They could no longer be incorporated in the bulb and reflector style headlight as before). To some, the first 1940 GM assemblies were simply "add-ons", maybe a quick design due to the fast industry acceptance of the...

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...

  When viewing older GM cars and trucks we see both colors of park light lenses. There seems to be no consistency that gives us the proof of what is actually correct, however, it is easy as remembering a year. Beginning in 1963, the Department of Transportation new regulations required park lights to show an amber color, to be seen...

Two major changes occurred in 6 volt General Motors sealed beam bulbs (are actually not sealed beams) since they were first installed on vehicle assembly lines in 1940. The perfectionist restoring his truck to exact original specifications must have the correct headlights for his year. In very competitive judging, it’s these details that can make a difference. No doubt, replacement...

Four Speed Backup Light Switch - They Did Exist! The first design of the 4-speed synchronized truck transmission, introduced in 1948, was used through about 1965. About mid series, when the dealer installed backup light increased in popularity, a special switch was attached to the base of the floor shift lever. This was the only location possible as there is...