Parking Brake System: Testing and Inspection

CHECK PARKING BRAKE OPERATION

Parking Brake Lever Locked:

- Pull the parking brake lever with 196 N (20 kgs, 44 lbs.) of force to fully apply the parking brake. The parking brake lever should be locked within the specified notches.

Lever Locked Notches: 4 - 8

If the number of lever clicks is excessive, inspect the parking brake shoe linings for wear.



If the parking brake linings are not worn beyond the service limit, minor adjustments (1-2 clicks) can be made with the adjusting nut in the equalizer.


COMPONENT INSPECTION

WARNING:
- Never use an air hose or dry brush to clean brake assemblies.
- Use an OSHA-approved vacuum cleaner to avoid breathing brake dust.
- Contaminated brake linings or drums reduce stopping ability.
- Block the front wheels before jacking up the rear of the vehicle.






1. Block the front wheels, loosen the rear wheel nuts slightly, support the rear of vehicle on safety stands, then remove the rear wheels.
2. Remove the rear caliper and rear brake disc/drum.
2. Check the brake linings for cracking, glazing, wear and contamination.

Measuring Brake Lining Thickness:

3. Measure the brake lining thickness.
NOTE: Measurement does not include brake shoe thickness.

Brake Lining Thickness:
- Standard: 1.9 - 2.5 mm (0.075 - 0.098 inch)
- Service Limit: 1.0 mm (0.040 inch)

CAUTION: After replacing the linings, be sure to drive the vehicle for "break-in" purposes. Refer to Parking Brake Shoe for break-in procedures.
Parking Brake Shoe





4. Measure the inside diameter of the drum.

Drum Inside Diameter:
- Standard: 169.9 - 170.0 mm (6.689 - 6.693 inch)
- Service Limit: 171.0 mm (6.732 inch)

5. Check the brake disc/drum for scoring, grooves and cracks.