2008 GMC C5500 Topkick Service and Repair Manual
This factory service and repair manual for the 2008 GMC C5500 Topkick covers the chassis in its 2-door conventional cab and chassis, crew cab and chassis, cutaway and cab and chassis cutaway forms, cataloged under six trim codes. Two engines carry the range: a turbocharged 6.6L overhead-valve V8 diesel of 403 cubic inches and a naturally aspirated 8.1L overhead-valve V8 gasoline engine of 496 cubic inches. Both are documented in full, and the chassis and electrical systems around them get the same treatment — procedures, specifications, torque values, wiring diagrams and diagnostics, arranged by system.
Engines covered
- 6.6L V8 (403 cu in) — OHV, turbocharged, diesel
- 8.1L V8 (496 cu in) — OHV, naturally aspirated, gasoline
Body styles covered
- 2-door cab & chassis, conventional
- Cab & chassis, crew cab
- Cutaway
- Cab & chassis, cutaway
Trims covered
- C5C042
- C5C044
- C5E042
- C5E044
- C5U042
- C5V042
Known issues on the 2008 C5500 Topkick. The two recalls on the federal record for the 2008 C5500 Topkick are both electrical, and both point at added equipment. In one, the epoxy potting compound inside a direct-current converter used on utility body conversions could turn conductive, then melt and burn, raising the risk of a fire. In the other, a protection diode in a wheelchair-lift interlock could fail under a voltage spike and let the truck move with the lift deployed. One owner complaint, on the electrical system, follows the same theme, and the wiring diagrams and circuit diagnostics here are the sections it points to.
