Check the disc brake rotor for scoring, cracks or other damage. Check the minimum thickness and rotor runout.
Either foreign material build-up or contamination on the rotor braking surface or uneven rotor thickness causes a brake pulsation that is present during brake application. If there is a foreign material build-up or contamination found on the rotor or lining surfaces, hand sand the linings and rotors. Uneven rotor thickness (thickness variation) may be caused by excessive runout, caliper drag or the abrasive action of the brake lining. If brake pulsation is present, attempt stopping the vehicle with the transmission in the NEUTRAL position. If the pulsation is gone, the drivetrain should be inspected. If the pulsation remains, inspect the brakes.
Check the rotor thickness using a micrometer or calipers. The brake rotor minimum thickness must not be less than 0.972 in. on 1988-91 vehicles or 0.974 in. on 1992-99 vehicles.
Rotor runout can be checked using a dial indicator. Mount the indicator to the spindle or upper control arm and position the indicator foot on the center of the braking surface. Rotate the rotor to check the runout. On 1992-99 vehicles, make sure there is no rust or foreign material between the rotor and hub face. Hold the rotor to the hub by inverting the lugnuts and tightening them to 85-105 ft. lbs. (115-142 Nm). Rotor runout must not exceed 0.003 in.
If rotor runout exceeds specification on 1988-91 vehicles, machine the rotor if it will not be below the minimum thickness specification after machining. On 1992-00 vehicles, the rotor can be repositioned on the hub to obtain the lowest possible runout. If runout remains excessive, remove the rotor and check the hub runout. Replace the hub if hub runout exceeds 0.002 in. If after replacing the hub, rotor runout remains excessive, machine the rotor if it will not be below the minimum thickness specification after machining.
Removal & Installation
- Before servicing the vehicle, refer to the Precautions section.
- Remove the wheel and tire assembly.
Remove the anchor plate as follows:
CAUTIONUse the correct type and length bolts when reinstalling.
Remove the bolts and position the brake caliper aside.
Match-mark the brake disc with a wheel stud.
NOTEIf the brake disc cannot be removed easily, apply rust penetrant on brake disc to wheel hub mating surfaces.
Remove the retention ring and the brake disc and discard the retention ring.
- Clean any rust or foreign material from the brake disc, wheel and wheel hub.
- Use brake parts cleaner to clean the brake disc and hub surfaces.
- Apply anti-seize lubricant to the hub mounting surface to prevent future corrosion.
- Install the rotor over the wheel studs with a new retention ring.
- Install the anchor plate with new bolts and torque to 118 ft. lbs. (160 Nm)