1956 GMC 1500 Facts
New changes to the GMC models hoped to help GMC gain in the truck selling industry. These changes included increased power, new axles, new transmissions, and new engineering developments such as 12 volt electrical systems and chassis improvements.
The 270c engine with 120 hp at 3200 RPM is standard in the PM150 and PM250 models while the 270 engine with 130 hp is standard in the 100 through 300 series. The new 316 cu. in. V8 engine with 180 hp replaces the 288 engine used the previous year and a new method of mounting the engine to the frame reduces vibration and increases mounting life. The 324 cu. in. V8 with 210 hp is also available in 550 and 600 series GMC's. Along with the new engine choices was the Hydra-Matic transmission.
Road Shock Damper (RSD) Suspension, a new GM development, also was available on GMC models. RSD gave light trucks the riding qualities of a passenger car and helped with eliminating road shocks. Other GMC options included directional signals, rearview mirrors, Hydrovac power brake, painted rear bumper, electric windshield wipers, power steering and more.