Brake Drum: Testing and Inspection

Rear Drum Brake Inspection

CAUTION
Frequent inhalation of brake pad dust, regardless of material composition, could be hazardous to your health.
- Avoid breathing dust particles.

- Never use an air hose or brush to clean brake assemblies. Use an OSHA-approved vacuum cleaner.


1. Raise the rear of the vehicle, and support it with safety stands in the proper locations. Service and Repair

2. Remove the rear wheels.

3. Release the parking brake, and remove the brake drum. Service and Repair






4. Check the wheel cylinder (A) for leakage.

5. Check the brake linings (B) for cracking, glazing, wear, and contamination.
NOTE: Contaminated brake linings or drums reduce stopping ability.

6. Measure the brake lining thickness (C). Measurement does not include brake shoe thickness.

Brake lining thickness:





7. If the brake lining thickness is less than the service limit, replace the brake shoes as a set.

8. Check the hub bearing unit (D) for smooth operation. If it requires servicing, replace the hub bearing unit. Service and Repair






9. Measure the inside diameter of the brake drum with inside vernier calipers.

Drum inside diameter:





10. If the inside diameter of the brake drum is more than the service limit, replace the brake drum.

11. Check the brake drum for scoring, grooves, corrosion, and cracks.

12. Install the brake drum. Service and Repair

13. Clean the mating surfaces between the brake drum and the inside of the wheel, then install the rear wheels.