Drum Brake Service Video

A drum brake slows the wheel by pressing curved brake shoes outward against the inside of a spinning drum. Many trucks, vans, and older sedans still use drum brakes on the rear axle. When you release the pedal, return springs pull the shoes back away from the drum.

This video opens up a rear drum so you can see the shoes, wheel cylinder, springs, and self-adjuster in place. It also sets worn hardware next to a fresh set, so the difference is easy to spot.

The wheel cylinder pushes the shoes out each time you brake, and the self-adjuster keeps them close to the drum as the lining wears. These parts work as one assembly. When a spring weakens or a cylinder starts to leak, the rest of the parts wear faster.

A grinding or scraping sound from the rear is the clearest sign the shoes have worn through. A parking brake that fails to hold your vehicle on a slope may indicate a problem with the rear drum brakes. On most drum-equipped vehicles, the parking brake uses the rear brake shoes to keep the vehicle in place. Drum service is part of our brake repair and safety inspection service, which covers every part of the braking system.

A soft pedal that sinks slowly can mean a leaking wheel cylinder. Brake fluid on the shoes ruins their grip, so the shoes must be replaced along with the cylinder.

At Spectra Auto Services, our technicians pull both rear drums and measure each drum against the maker's wear limit. You get DVI photos of the shoe lining and hardware before any work is approved. A drum within specification can often be reused, while one past the limit is replaced.

Rear drum service is often paired with our brake pad replacement service for the front axle, since both wear over the same miles. Drivers from Brunswick and Mount Airy often have us check both axles in one visit.

Winter road salt can seep past the edges of brake drums and cause corrosion inside. Over time, it can seize the wheel cylinder pistons and self-adjuster, preventing the brake shoes from adjusting properly as they wear.

If your rear brakes grind or your parking brake slips, call Spectra Auto Services at (301) 695-5990, or book auto repair in Frederick to have your drums inspected.