This factory service and repair manual for the 1990 GMC W5500 Forward covers the low tilt straight truck exactly as it left the plant: one body configuration, one trim code, W5R042, and one diesel engine. That engine is the 6.5L inline-six of 396 cubic inches, naturally aspirated rather than turbocharged, which keeps the induction side of the book comparatively short. The remaining chapters give the chassis and electrical systems their own procedures, specifications and torque values.
Engines covered
- 6.5L inline-six (396 cu in) — naturally aspirated, diesel
Body styles covered
- Straight truck, low tilt
Trims covered
- W5R042
Known issues on the 1990 W5500 Forward. Nothing is recorded against the 1990 W5500 Forward at the federal level: no recalls, and no owner complaints registered with NHTSA. With no known trouble spot to work around, the manual is used the way any factory book is, for diagnostics on the naturally aspirated 6.5L inline-six, for the specifications and torque values that govern reassembly, and for the wiring diagrams that make an intermittent circuit fault traceable rather than guessed at.
