Brake Rotor Thickness Measurement
WARNING: This page is about a different car, the 2006 Pontiac Montana SV6, 2006 Chevrolet Uplander, and 2006 Buick Terraza. However, it is still accessible from the selected car via links, so may be relevant.
- Clean the brake pad lining contact surface of the brake rotor with denatured alcohol or an equivalent brake cleaner.
- Using a micrometer calibrated in ten-thousandths of an inch, 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.
- Compare the lowest thickness measurement recorded to the following specifications:
Specification:
- Front brake rotor minimum allowable thickness after refinishing - 31.08 mm (1.22 in).
- Rear brake rotor minimum allowable thickness after refinishing - 10.8 mm (0.425 in).
- 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.
- 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.
- Compare the lowest thickness measurement recorded to the following specifications:
Specification:
- Front brake rotor discard thickness - 30.7 mm (1.21 in).
- Rear brake rotor discard thickness - 10.5 mm (0.413 in).
- If the lowest thickness measurement of the brake rotor is at or below the discard thickness specification, the rotor requires replacement.