GMC · Canada · Mod
GMC Topkick 7500, Topkick 8500: Brakes
Affects GMC Topkick 7500, Topkick 8500 · 2007 — about 103 vehicles.
The hazard
On certain conventional and tilt cab trucks, the air compressor may not build enough air pressure to support the air brake system. If this condition were to occur while the vehicle was stationary (brakes applied) the air brakes would remain applied and prevent the vehicle from moving. If this were to occur while the vehicle was in motion, the dual system air pressure gauges would register the drop in pressure, which could trigger the low air pressure warning buzzer and illuminate the warning indicator lamp. If these warnings are ignored and there is continued loss of pressure, the rear spring brakes would automatically apply, preventing the truck from being driven. Correction: Dealers will replace the air compressor head.
What to do
Contact your dealer; the remedy details were not included in the filing.