2006 GMC W4500 Forward Service and Repair Manual
This factory service and repair manual for the 2006 GMC W4500 Forward deals with a truck serviced through its tilting cab — a low-tilt straight truck in the W4S042 build — and with the two engines under it: a naturally aspirated 6.0L overhead-valve V8 displacing 364 cubic inches, and a turbocharged 5.2L inline-four diesel of 317. Chapters are grouped by system, engine and fuel through to cab and electrical, each with procedures, specifications, torque values, wiring diagrams and diagnostics, so the order of access is clear before anything is loosened.
Engines covered
- 6.0L V8 (364 cu in) — OHV, naturally aspirated, gasoline
- 5.2L inline-four (317 cu in) — turbocharged, diesel
Body styles covered
- Straight truck, low tilt
Trims covered
- W4S042
Known issues on the 2006 W4500 Forward. Three separate recalls attach to this model year. One covers fuel tanks that can corrode until they leak, with the fire risk a leak brings. Another involves diesel fuel seeping from the pipe at a port on the supply pump. The third concerns oil pipe bolts that were under-tightened in assembly and can work loose, letting oil out past the packing seals until the engine seizes and the truck decelerates suddenly. Three owner complaints are recorded, on the fuel and propulsion system, the fuel system and the electrical system. Fuel and lubrication coverage here is thorough.
