GM Cutlass RWD 1970-1987 Repair Guide

Brake Disc (Rotor)

Print

REMOVAL & INSTALLATION



  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.  

To install:
  1. 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. (16 Nm)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.  

  2.  
  3. Install the wheel and tire assembly, remove the jackstands and lower the vehicle.
  4.  

INSPECTION



See Figure 1

  1. Check the disc for any obvious defects such as excessive rust, chipping, or deep scoring. Light scoring is normal on disc brakes.
  2.  
  3. Make sure there is no wheel bearing play and then check the disc for runout as follows:
  4.  
  5. Install a dial indicator on the caliper so that its feeler will contact the disc about one inch below its outer edge.
  6.  
  7. Turn the disc and observe the runout reading. If the reading exceeds 0.002 in. (0.05mm) the disc should be replaced.
  8.  



Click image to see an enlarged view

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

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.

 
label.common.footer.alt.autozoneLogo