Thickness

CAUTION: To maintain safe braking performance, the disc brake rotors must be kept within allowable service specifications.

Before re-finishing or re-processing the brake disc surface, the following conditions should be observed:
- Check for scratches, rust, saturated lining materials and wear. If the vehicle is not driven for a certain period, the sections of the discs that are not in contact with the lining will become rusty, causing noise and shuddering. If grooves resulting from from excessive disc wear and scratches are not removed prior to installing a new pad assembly, there will momentarily be inappropriate contact between the disc and the lining pad.
- Change in thickness (parallelism). If the thickness of the disc changes, this will cause pedal pulsation, shuddering and surging.
- Inset or warping. Overheating and improper handling while servicing will cause inset or warping.





1. Using a micrometer, measure disc thickness at eight positions, approximately 45° apart and 10 mm (0.39 inch) in from the outer edge of the disc. Brake disc thickness Standard value is 24 mm (0.94 inch) The limit is 22.4 mm (0.88 inch). Thickness variation measured from at least 8 positions should not be more than 0.015 mm (0.0006 inch.)
2. If the disc is beyond the limits for thickness, remove it and install a new one. If thickness variation exceeds the specification, replace the brake disc or turn rotor with an on the car type brake lathe (Accuturn-8750, or equivalent). Be sure to follow the exact brake lathe manufacturer instructions.