Brake linings wear, and when they are worn, you replace them. If that’s all you think a brake job entails, you’re wrong. n Braking a truck requires a long chain of parts that cooperate in pressing that lining evenly against the drum. Every one needs to be regularly inspected or replaced if you want those brakes to work properly. Such care also prevents more costly repairs later, not to mention loss of revenue when inspectors put you out of service, says Rod Russell, product specialist for brake systems and wheel ends at Dana Corp.

“Few people realize the importance that these parts have in brake longevity,” says John Ferry, general manager of TransAxle Corp. of Cinnaminson, N.J., a distributor of remanufactured truck parts.

The secret to long brake life is even application – using the whole lining, not just part of it, to spread the work out. You also need both linings on a wheel to share the load evenly so that one doesn’t wear prematurely and stopping power is maximized.

We all know brake linings wear fast, but the hard parts in the system wear fast, too. There is no way you will get a good brake job unless you inspect everything and throw away anything that isn’t in near-perfect condition. Even when you are doing brakes because of a problem on a single wheel – say, a leaky seal – always replace the same parts on both ends of the axle for the sake of balance. And speaking of seals, you must fix any wheel seal leaks before proceeding with brake work, says Dave Edwards, director of global technology programs at ArvinMeritor. Oily linings won’t stop you.

Technicians should always inspect the worn parts during disassembly, says Larry Gilles of the Tech Team Group at Bendix Commercial Vehicle Systems. Worn parts reveal problems that need to be fixed. If you see a tech just ripping brake parts off and throwing them into a trashcan without examination, go elsewhere.

Shoes. You can’t just re-use shoes, Gilles says. Brake lining applies tightly to the drum only if backed up by the shoe table. Wherever this support is missing because of a gap between lining and table, or uneven because of a rust bulge called rust jacking, you will get a crack. After a set of brakes has gone through two winter seasons, there will be rust and flat spots, as well, because stress distorts the shoe table, Gilles says. This will put uneven heat stress on the lining and crack it. A crack all the way across will put you out of service.