The Stovebolt Site Forums The Shop Area Engine Shop GMC truck engines

GMC used mostly Pontiac and Oldsmobile flathead 6 cylinders through the '30s, seems Pontiac engines were used up to '33, Olds engines '34 and later, though there was some models that used Pontiac engines later than '33. This excludes certain models (mostly 1.5 and larger) that used Buick engines. In '39, GMC used their own engines in lighter trucks, heavy trucks still used the Buick based 6 cylinder.