Brake Rotor Thickness Measurement

Brake Rotor Thickness Measurement

Caution: Refer to Brake Dust Caution in Service Precautions.





1. Clean the brake pad lining contact surface of the brake rotor with denatured alcohol or an equivalent brake cleaner.
2. Using a calibrated micrometer measure and record the lowest thickness of the brake rotor at 4 or more points equally spaced around the rotor.
Ensure that the measurements are only taken within the brake pad lining contact area and that the micrometer is positioned the same distance from the outside edge of the rotor for each measurement.
3. Compare the lowest thickness measurement recorded to the following specifications:
^ Specification-Front Brake JC5/JH5
- Brake rotor minimum allowable thickness after refinishing 28.0 mm (1.10 inch)
- Brake rotor discard thickness 27.50 mm (1.082 inch)
^ Specification-Front Brake JH6/JH7
- Brake rotor minimum allowable thickness after refinishing 37.0 mm (1.46 inch)
- Brake rotor discard thickness 36.50 mm (1.437 inch)
^ Specification-Rear Brake JC5/JH5 Pickup
- Brake rotor minimum allowable thickness after refinishing 19.0 mm (0.748 inch)
- Brake rotor discard thickness 18.50 mm (0.728 inch)
^ Specification-Rear Brake JH6
- Brake rotor minimum allowable thickness after refinishing 28.0 mm (1.102 inch)
- Brake rotor discard thickness 27.50 mm (1.082 inch)
^ Specification-Rear Brake JH7
- Brake rotor minimum allowable thickness after refinishing 29.0 mm (1.142 inch)
- Brake rotor discard thickness 28.50 mm (1.122 inch)

4. If the lowest thickness measurement of the brake rotor is above the minimum allowable thickness after refinishing specification; the rotor may be able to be refinished, depending upon surface and wear conditions which may be present.
5. If the lowest thickness measurement of the brake rotor is at or below the minimum allowable thickness after refinishing specification; the rotor may not be refinished.
6. If the lowest thickness measurement of the brake rotor is at or below the discard thickness specification; the rotor requires replacement.