Though 1937 GMC pickups were made in both Canada and the US, there is one major difference between them. They have very different engines. Here are some facts:
The 1937 US made GMC ½ tons used a flat head six cylinder engine from an Oldsmobile and in 1938 a flat head from Pontiac. These automobile engines were dependable with a proven record. This saved the egos of the US GMC dealers from trying to explain to customers why these “high-end” pickups were using the competitor’s engine.
In the US, the first year for the GMC ½ ton was 1936. They were all the longer 125 inch wheel base. The following year the GMC pickup was introduced in Canada and were made in the GM assembly plant in Oshawa, Ontario Canada. Just like GMC in the US in 1937, Canada offered a short wheel base 112” and optional long bed 125” wheel base. The Canadian Pontiac dealers were given this pickup to market alongside their car line. Unlike the US, there were no stand-alone dealerships for these new GMC pickups!
The long awaited introduction of the 216 six cylinder overhead valve engine was in 1937. It was used in Chevrolet cars and trucks in Canada and the US. This engine was quite successful for the existing roads in both countries. It was used in production Chevrolet vehicles 16 years.
When the GMC pickup first came on the market in Canada, it was given more horsepower than Chevys ½ ton. GM did this by adding a 216 Chevrolet engine with bored cylinders to create 224 cubic inches. This bore sizes increased from 3 ½” to 3 9/16”. Aluminum pistons also added more power over the Chevy cast iron units.
It appears the engineers designing the GMC pickup in the US wanted no part of using a Chevy engine for their first introduction into the pickup truck market. (GMC had previously been the big truck arm of General Motors). Because the Great Depression of the mid 1930’s GM needed to make emergency changes. Big truck sales in the US had reached such low numbers that something (a small pickup truck) had to happen quickly. Many US GMC dealers had gone out of business. Some were surviving only by repair work or selling additional products such as farm equipment, used cars and laying off employees.
In Canada financial disaster was not as imminent as there were no dealerships that sold only large GMC trucks. The newly introduced 1937 GMC pickup would not be marketed in a one marque location. GM of Canada used the new GMC to help the Pontiac dealers that were also feeling low sales. These dealers would probably be required to stock only a few GMC pickups and a basic supply of repair parts. After all, the Canadian Chevrolet car and truck dealer would also have a supply of new mechanical parts that covered all the items that the GMC pickup needed, except for aluminum pistons. Many of the Pontiac / GMC dealers would probably obtain the mechanical parts from local Chevy dealer and not wait for an order from Oshawa, Ontario of a week or more.
The big engine change for GMC in the USA was in 1939. Now GMC had developed their own six cylinder engine. All GMC pickups came with a 228 cubic inch power plant had overhead valves in the head.