GM Buick/Oldsmobile/Pontiac/Full-Size 1975-1990 Repair Guide

Brake Disc (Rotor)

Print

REMOVAL & INSTALLATION



See Figure 1

  1. Raise the vehicle, support it with jackstands, and remove the wheel and tire assembly.
  2.  
  3. Remove the brake caliper as previously outlined.
  4.  
  5. Remove the dust cap and remove the wheel bearing nut after removing the cotter pin.
  6.  
  7. Remove the wheel bearing, hub, and disc assembly from the spindle.
  8.  
  9. Install the disc, bearing, washer and nut. Adjust the wheel bearing as follows:
    1. Spin the wheel forward by hand. Torque the nut to 12 ft. lbs. to fully seat the bearings.
    2.  
    3. Back off the nut 1 / 4 - 1 / 2 turn until it is just loose, the tighten the nut finger tight.
    4.  
    5. Loosen the nut until either hole in the spindle lines up with a slot in the nut and then insert the cotter pin. This may appear to be too loose, but it is the correct adjustment.
    6.  
    7. Proper adjustment creates a 0.001-0.005 in. (0.025-0.127mm) of end play.
    8.  

  10.  



Click image to see an enlarged view

Fig. Fig. 1: Exploded view of the disc brake assembly

INSPECTION



See Figures 2 and 3

All brake rotors (discs) have a minimum thickness dimension cast into them, on the hub between the lugs. This is the minimum wear dimension and not a refinish dimension. Do not reuse a brake rotor that will not meet specifications. Replace with a new rotor.

Refinishing of brake rotors can be handled at machine shops equipped for brake work.



Click image to see an enlarged view

Fig. Fig. 2: Checking runout with a dial indicator



Click image to see an enlarged view

Fig. Fig. 3: The discard dimension is stamped on the disc hub

 
label.common.footer.alt.autozoneLogo