1987 GMC Truck Specificationsby Jay Bradlley
General Motors Co. (GMC) truck specs for 1987 vary by the make and model of truck. Most 1987 GMC trucks had the same frame and parts as most other GM truck products on the market in the late 1980s.
1987 regular production options (RPO) of GMC trucks had a V-8 engine with a displacement of 454 cubic inches and was capable of 230 horsepower. The truck had 385 foot-pounds of torque and available models included a sedan pick-up or four-door cab.
All RPO transmissions were standard four-wheel drive (4WD). GMC offered a four-speed manual on half-ton to 1-ton truck models with a gear ratio of 6.55, 3.58, 1.70 and 1-to-1 on those models. The four-speed automatic and the four-speed manual transmission with overdrive was available on the half-ton and three-quarters ton truck models with a gear ratio of 3.06, 1.63, 1.0 and 0.7-to-1 in 1987.
Axles and Ratio
In 1987 the half-ton models had a 2.73 to 4.1-to-1 axle ratio. The three-quarter ton trucks had a ratio of 3.23 to 4.1-to-1 and the one-ton trucks had an axle ratio of 3.73 to 4.56-to-1 axle ratio depending on the make and model of the truck.
In 1987, two different transfer cases were available. The NP 205 was a gear driven cast iron case. The NP 205 has a low ratio of 1.96-to-1 and a high ratio of 1-to-1. The NP 208 is an aluminum case chain driven unit with a low ratio of 2.61-to-1 and a high ratio of 1-to-1.
Jay Bradley has been writing professionally since 2009. His articles appear on eHow. Bradley holds a Bachelor of Arts in English and secondary education with a minor in psychology from Saginaw Valley State University.