The Original Specifications on the 1950 GMC Truckby Rob Wagner
The 1950 GMC truck is a slightly bigger, more powerful and stronger version of the 1950 Chevrolet truck. The GMC and Chevrolet trucks shared identical transmissions, suspension and bodies, but the GMC featured a thicker frame and larger engine. Chevy pickups shared its engines with General Motors’ automotive lines. GMC had specially manufactured truck engines. Although GMC and Chevrolet shared most of the same sheet metal, GMCs had a distinctive grille, tailgate, hubcaps and exterior colors.
The 1950 GMC base engine for the half-ton pickup was the 228-cubic-inch in-line six-cylinder. In contrast, the base Chevrolet model featured the smaller 216.5-cubic-inch straight-six. The 93-horsepower 228 had a 3.6-inch cylinder bore and a 3.8-inch stroke. The 228’s compression ratio was 8-to-1. The optional 110-horsepower 248 straight-six had a 3.7-inch bore and 3.8-inch stroke and 7.5-1 compression. The biggest powerplant available on the GMC truck was the 115-horsepower 270 six-cylinder with a 3.7-inch bore and 4-inch stroke. The 270’s compression ratio was 7.5-to-1. Canadian versions of the 1950 GMC truck were equipped with Chevrolet’s 216 straight-six with 228 and 248 available as options. Another significant difference between the GMC and Chevy models was that the GMC used a six-volt positive ground electrical system, while Chevrolet was equipped with a six-volt negative ground system.
Like its Chevy sibling, the GMC pickup included the half-ton, three-quarter ton and 1-ton models. The Chevys featured wheelbase of 116, 125.25 and 137 inches, while the GMC wheelbases were two inches longer for each of the three models to accommodate the larger engines. Body dimensions, however, were identical with the cargo boxes measuring 50 inches wide and 78, 87 or 108 inches long. The 1.5-ton and larger GMC stake bed and flatbed trucks rode on either a 137-inch wheelbase with a 105.5-inch bed and 9-foot total length or a 161-inch wheelbase with 148-inch bed and a 12-foot total length.
Chassis, Brakes and Suspension
All GMC trucks featured all-wheel drum brakes, a forged steel I-beam front axle and hypoid single reduction full floating rear axle. The rear suspension featured steel leaf springs with the front and rear both equipped with tubular shock absorbers. A three- or four-speed manual transmission matched the engines. The four-speed was optional on the half-ton and three-quarter ton models and standard on the 1-ton and larger versions. For 1950, General Motors engineers abandoned the process of bolting together the cab and welded the cab to minimize road noise and vibrations caused by the stiff frame. The cab also rode on the frame cushioned with a three-point suspension system for a smooth ride. The gross vehicle weight rating ranged from the half-ton’s 4,100 lbs. to the 3-ton’s 26,000-lb. rating.