1990 GMC C2500 Service and Repair Manual
This factory service and repair manual for the 1990 GMC C2500 takes in four engines, three of them gasoline, the 4.3L V6 and the 5.0L and 5.7L V8s, and one diesel, the 6.2L V8. All are naturally aspirated overhead-valve designs. The truck came as a standard cab pickup, an extended cab pickup or a cab and chassis, in Sierra, Sierra SLE or Sierra SLX trim, and each of those configurations carries its own body and mounting procedures alongside the mechanical sections they all share.
Engines covered
- 5.0L V8 (305 cu in) — OHV, naturally aspirated, gasoline
- 6.2L V8 (379 cu in) — OHV, naturally aspirated, diesel
- 4.3L V6 (262 cu in) — OHV, naturally aspirated, gasoline
- 5.7L V8 (350 cu in) — OHV, naturally aspirated, gasoline
Body styles covered
- 2-door standard cab pickup
- 2-door extended cab pickup
- 2-door cab & chassis
Trims covered
- Sierra
- Sierra SLE
- Sierra SLX
Known issues on the 1990 C2500. Three recalls apply to this model year. One is an instruction fault: the guidance supplied for adjusting the rear lap-shoulder belts was incorrect, so a belt set by it might not restrain an occupant in a sudden stop. Another involves transmission fluid pushed out of the vent tube by unexpected heat and able to ignite. The third concerns replacement oil filters that could seal badly and lose engine oil. Six owner complaints are logged, four on structure and two on seat belts, both areas the body and restraint sections cover.
CERTAIN HONEYWELL FRAM RACING BRAND HP4 AND HP8 OIL FILTERS THAT WERE MANUFACTURED FROM MAY 25, 2006, THROUGH SEPTEMBER 14, 2007, AND SOLD FOR USE AS REPLACEMENT EQUIPMENT FOR VEHICLES LIST ABOVE. TH
THIS CONDITION MAY CAUSE INADEQUATE SEALING AND LOSS OF ENGINE OIL, POSSIBLY RESULTING IN A FIRE.
HONEYWELL WILL REPLACE THE AFFECTED OIL FILTERS FREE OF CHARGE. THE RECALL BEGAN DURING NOVEMBER 20
TRUCKS CAN CONTAIN INCORRECT INSTRUCTIONS ON HOW TO PROPERLY ADJUST REAR SEAT LAP-SHOULDER BELTS AS REQUIRED BY FMVSS 209.
INCORRECTLY ADJUSTED SEAT BELT WOULD NOT PROPERLYRESTRAIN OCCUPANT IN AN ACCIDENT OF SUDDEN STOP; TR
PROVIDE OWNER'S MANUAL INSERT CONTAINING THE CORRECT REAR LAP-SHOULDER BELT INSTRUCTIONS.
UNANTICIPATED HEAT IN THE TRANSMISSION CAN FORCE THE TRANSMISSION FLUID OUT OF THE VENT TUBE.
THE VENTED TRANSMISSION FLUID CAN CATCH FIRE IF EXPOSEDTO A SOURCE OF IGNITION.
INSTALL A LONGER TRANSMISSION VENT HOSE ROUTED TO THE LEFT SIDE OF THE ENGINE COMPARTMENT OF THE VEH
FRONT SEAT BELTS NON-OPERATIONAL. CABLE WIRE IS COMMING APART. PASSENGER SIDE SEATBEALT MECHANISM BROKEN
FRONT SEAT BELTS NON-OPERATIONAL. CABLE WIRE IS COMMING APART. PASSENGER SIDE SEATBEALT MECHANISM BROKEN
FRONT SEAT BELTS NON-OPERATIONAL. CABLE WIRE IS COMMING APART. PASSENGER SIDE SEATBEALT MECHANISM BROKEN
MAIN FRAME OF THE VEHICLE HAS SEVERAL CRACKS.
MAIN CROSS MEMBER SUPPORT TO FRAME AND ENGINE CRACKED.
Showing the 5 most serious of 8 complaints filed with NHTSA.
