Table 1 shows two common service brakes related problems of the 2003 GMC C4500.
| Problem Category | Number of Problems |
|---|---|
| Brake Disc Caliper problems | |
| Power Assist Hydraulic Brake problems |
Vehicle was experiencing a problem with grease from the rear end leaking onto the left rear wheel braking system. This caused loss of braking in that wheel. Dealer replaced the grease seal with an upgraded seal six times, problem recurred. Real grease seal was replaced. The driver side brake caliper bolt fell out causing the caliper to rub the inside of the inner dual wheel causing damage to the caliper and wheel.
My engine stalled due to contaminated fuel. With the key still in the on position, I attempted to stop. I pressed the service brake pedal. The backup brake system did not operate. I repeated pressing the brake pedal two more times. I understood. I was closing the distance between my vehicle and the one in front of me approaching the traffic signal, red. The brake pedal switch failed to initiate the relays and pump. Consequently, the vehicle had practically no brakes other than the drum brake by hand brake handle. I applied the hand brake. Good thing I was only traveling at less than 30 miles per hour, without cargo, and had more than 400 feet to stop. I almost hit the vehicle in front at the red light. The hand brake worked. At higher speed, the truck would have killed people. There would have been no engine brake effect because the engine had stopped. Going downhill after fueling and then pulling my trailer as well if it had been loaded, would the results had been the same at the red light at the bottom of a hill or rail road track bridge? someone would have died. There needs to be a bypass switch installed near the steering wheel to manually turn the pump on. And the switch on the pedal needs to be a mechanical one like the ones that have operated taillights for the last fifty years. Stick with what works.