1988 GMC K1500 Service and Repair Manual

This factory service and repair manual for the 1988 GMC K1500 covers two cab lengths, the 2-door standard cab pickup and the 2-door extended cab pickup, in Sierra, Sierra SLE and Sierra SLX trim. Engine choice stays wide: the 5.0L and 5.7L gasoline V8s, the 4.3L gasoline V6 and the 6.2L diesel V8, all overhead-valve and naturally aspirated. Procedures, specifications, torque values, wiring diagrams and diagnostics are arranged by system, with cab-length differences called out wherever they change how a job is done.

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

Trims covered

• Sierra
• Sierra SLE
• Sierra SLX

Known issues on the 1988 K1500. Of the two recalls here, the first covers replacement oil filters that can seal poorly and let engine oil escape, with fire the consequence if it reaches something hot. The other is a transmission problem: unanticipated heat can push fluid out of the vent tube, and vented fluid will burn if it finds an ignition source. A single owner complaint is logged with NHTSA, concerning the suspension. Transmission overhaul and cooling, lubrication service, and front suspension procedures with their torque values are all set out in this manual.