This factory service and repair manual for the 1991 GMC R1500 Suburban is a single-trim book — Base only — for the four-door sport utility, and it covers two overhead-valve V8s: a naturally aspirated 6.2L diesel of 379 cubic inches and a 5.7L gasoline engine of 350 cubic inches. With the range that narrow, the coverage is concentrated, and the engine, fuel, cooling, driveline, brake, suspension and body electrical systems each get their own procedures, specifications, torque values, wiring diagrams and diagnostics.
Engines covered
- 6.2L V8 (379 cu in) — OHV, naturally aspirated, diesel
- 5.7L V8 (350 cu in) — OHV, naturally aspirated, gasoline
Body styles covered
- 4-door sport utility
Trims covered
- Base
Known issues on the 1991 R1500 Suburban. The federal record carries one recall for this year, concerning replacement oil filters that could fail to seal properly and allow engine oil to escape, which raises the possibility of a fire. One owner complaint is logged, and it falls under the fuel system. Between the two, lubrication and fuel delivery are the systems worth reading closely here: the manual gives oil pressure and lubrication specifications for both V8s, injection procedures for the 6.2L diesel, fuel system diagnostics, and the torque values for the components involved.
