The braking system of a truck is an embattled entity. Perhaps more than any other system, its foes are numerous and often difficult to contend with. But that doesn’t mean you have to throw in the shop rag and surrender. Use the tools your expertise and knowledge afford you to perform good brake jobs and educate drivers about how they can avert road peril to lengthen brake life, and you should set your customers up for smooth sailing-and seamless stopping.
The first step toward helping your customer get the most from his braking system is to know a braking system’s enemies. First, there are the uncontrollable factors that can stress a truck’s braking system, such as poor road conditions or erratic drivers. Over these occurrences, you have little control.
But there are other factors that cause premature brake wear that you can battle. One leading such factor is heat. A brake’s first job is to stop a vehicle, then control the heat that the stop generates.
Dennis Griffin, product manager, Abex Heavy-Duty Friction, Federal-Mogul Corp., said, “As brake temperatures rise, the wear rate of the friction material increases. Causes of excessive heat include duty-cycle, mismatched brake linings and component malfunction.”
If a truck operates in a severe-service environment, duty-cycle is a major obstacle to brake life. For example, brakes on stop-and-go applications, such as dump trucks and city vehicles, tend to wear faster because they don’t cool down between applications.
Make sure you match the correct brake lining to a vehicle’s service. For example, brake lining designed for an on-highway truck will wear at a much faster rate if it’s installed on a severe-service vehicle. It’s also necessary to have matching brake linings on the same truck.
“If you use different brake linings on a tandem axle, the lining with the best stopping power is going to wear faster because it will be doing more of the work. That’s why it’s important to replace all of the shoes on a tandem axle rather than just the axle that is experiencing more wear,” Griffin said.
