How to Troubleshoot Brake Drum Problems

Cars and trucks have relied on drum brakes from the inception of motorized vehicles. Disc brakes have been introduced since then, but vehicles are still being made with drum brake technology on one or multiple axles. Know how to troubleshoot brake drum problems to protect your drum brake shoes. Diagnose brake drum problems quickly, and get a long life out of regularly replaced brake shoes.

Instructions

1

Inspect drum brakes when sounds come from the brakes when braking or pedal reaction when applying pressure on the pedal. A spongy pedal feels like stepping on a cloud instead of the firm resistance of a properly working brake system.

2

'Break' the lug nuts on one wheel. Breaking a lug nut refers to loosening, but not removing, the lug nut from the wheel stud. Break all of the wheel lugs before lifting the vehicle. Lift the vehicle off the ground, so the wheel can be removed, exposing the drum brake.

3

Remove the brake drum, using a hammer to tap the back edge of the drum brake housing. Hitting the brake drum will move it off the wheel studs. Move around the edge of the brake drum, tapping it with a hammer until the hub comes free. Remove the hub from the axle, and bring it to a work bench for inspection.

4

Check the brake drum lining for scoring and grooves, which indicate the brake shoes have worn unevenly. This reduces the stopping power of drum brakes and can result in a spongy brake pedal. These grooves may also be producing the noise when the brakes are applied, as the pressure is grinding the metal surface of the lining.

5

Measure the thickness of drum brake linings in several locations to determine its thickness. A perfectly smooth surface should have a thickness of no less than 1/8". Repeat the inspection on the other drum brake linings.