Brake Rotor Thickness Measurement
WARNING: This page is about a different car, the 2003 Pontiac Sunfire and 2003 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
- If the inboard friction surface of the brake rotor is not accessible, reposition and support the caliper with the brake pads.
- Clean the friction surfaces of the brake rotor with denatured alcohol, or an equivalent approved brake cleaner.
- Using a micrometer calibrated in thousanths-of-a-millimeter, or ten-thousanths-of-an-inch, measure and record the thickness of the brake rotor at 4 or more points, evenly spaced around the rotor. Ensure that the measurements are only taken within the friction surfaces and that the micrometer is positioned the same distance from the outer edge of the rotor, about 1/2 in. (13 mm), for each measurement.
- Compare the lowest thickness measurement recorded to the following specifications. See BRAKE ROTOR SPECIFICATIONS
table.BRAKE ROTOR SPECIFICATIONS
Application In. (mm) Brake Rotor Minimum Allowable Thickness After Refinishing 0.739 (18.776) Brake Rotor Discard Thickness 0.736 (18.70) - 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.
- If the lowest thickness measurement of the brake rotor is at or below the discard thickness specification, the rotor requires replacement.