GM Service Manual Online
For 1990-2009 cars only
Makes
🢒
GMC_Truck
🢒
2005
🢒
TopKick C-Series (Conventional) C4/C5
🢒
Brakes
🢒
Air Compressor
🢒 Air Compressor Not Unloading
Problem
Action
Faulty governor or governor installation
Test the governor for proper operation and inspect air lines to and from the governor for kinks or restrictions.
Replace or repair the governor or its connecting air lines.
Faulty or worn unloader pistons or bores
Inspect for worn, dirty or corroded unloader pistons and their bores.
Replace as necessary.