GM Caprice 1990-1993 Repair Guide

Brake Disc (Rotor)



Brake pads contain asbestos, which has been determined to be a cancer causing agent. Never clean the brake surfaces with compressed air! Avoid inhaling any dust from any brake surface! When cleaning brake surfaces, use a commercially available brake cleaning fluid.

  1. Remove the caliper by following instructions of caliper removal procedure.
  3. Remove dust cap, cotter pin, castle nut, thrust washer and outside wheel bearing. Pull the disc/hub assembly from the steering knuckle.
  5. To install, position the disc/hub assembly to the spindle/steering knuckle.
  7. Install the outside wheel bearing, thrust washer and castle nut. Tighten the castle nut until the bearing is snug. Back off the nut 1 / 4 turn. Refer to for Wheel Bearing Removal and Installation, and Adjustment.
  9. Install the cotter pin and dust cap.


See Figures 1 and 2

Click image to see an enlarged view

Fig. Fig. 1: Check the disc rotor runout using a dial indicator

Click image to see an enlarged view

Fig. Fig. 2: Examples of disc rotor inspection

  1. Check the rotor surface for wear, scoring, grooves or rust pitting. Rotor damage can be corrected by refacing, consult your local garage or machine shop. If the damage exceeds the minimum thickness, which is stamped on the rotor, replace the rotor.
  3. Check the rotor parallelism at four or more points around the circumference, it must not vary more than 0.0005inch (0.013mm). Make all measurements at the same distance in from the edge of the rotor. Refinish the rotor if it fails to meet specification.
  5. Measure the disc runout with a dial indicator. If runout exceeds 0.004 inch (0.10mm), and the wheel bearings are okay (runout is measured with the disc on the car), the rotor must be refaced or replaced.