1985 GMC C2500 Service and Repair Manual

This factory service and repair manual for the 1985 GMC C2500 lists six engines, and the spread is unusually wide: a 4.3L V6, a 4.8L inline-six, three gasoline V8s of 5.0, 5.7 and 7.4 liters, and a 6.2L diesel V8. All are overhead-valve and naturally aspirated. The truck itself is offered as a crew cab pickup, a standard cab pickup or a cab and chassis, in Base, High Sierra or Sierra Classic trim, and the chassis sections of the book apply across all three.

Engines covered

• 5.0L V8 (305 cu in) — OHV, naturally aspirated, gasoline
• 7.4L V8 (454 cu in) — OHV, naturally aspirated, gasoline
• 6.2L V8 (379 cu in) — OHV, naturally aspirated, diesel
• 4.8L inline-six (292 cu in) — OHV, naturally aspirated, gasoline
• 4.3L V6 (262 cu in) — OHV, naturally aspirated, gasoline
• 5.7L V8 (350 cu in) — OHV, naturally aspirated, gasoline

Body styles covered

• 4-door crew cab pickup
• 2-door standard cab pickup
• 2-door cab & chassis

Trims covered

• Base
• High Sierra
• Sierra Classic

Known issues on the 1985 C2500. Nothing is logged against this model year with NHTSA, neither recalls nor owner complaints. That puts the weight on ordinary reference work, and there is plenty of it: six engines to specify and overhaul, three body configurations with their own mounting and trim procedures, and a chassis whose brakes, steering, suspension and axles each carry adjustment figures and torque values of their own. Wiring diagrams and diagnostic sequences support the electrical side.