This factory service and repair manual for the 1991 Chevrolet C3500HD covers the heavy-duty chassis of the one-ton line, and it came one way only: a two-door conventional cab and chassis in Base trim, waiting for a body builder. Three overhead-valve V8s stand behind it — the 7.4-liter 454 and 5.7-liter 350 on gasoline, and the 6.2-liter 379-cubic-inch naturally aspirated diesel for operators who wanted torque and range. One body and one trim keep the wiring diagrams and dimensional specifications tightly scoped.
Engines covered
- 7.4L V8 (454 cu in) — OHV, naturally aspirated, gasoline
- 6.2L V8 (379 cu in) — OHV, naturally aspirated, diesel
- 5.7L V8 (350 cu in) — OHV, naturally aspirated, gasoline
Body styles covered
- 2-door cab & chassis, conventional
Trims covered
- Base
Known issues on the 1991 C3500HD. A single recall is on the federal record for this chassis. It concerns replacement fuel filters whose connection may not seal, so fuel can escape and, near an ignition source, catch fire. Three owner complaints exist, one each against tires, structure and the power train. On a truck that spends its life carrying a mounted body, those are the systems worth checking, and the manual specifies fuel line routing and filter service, frame and crossmember repair, and transmission and driveline diagnosis, with torque values given for each.
