Chrysler Full-Size Trucks 1967-1988 Repair Guide

Brake Disc (Rotor)


Brake shoes 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.


See Figures 1 and 2

  1. Loosen the lug nuts slightly before you jack up the front of the truck and support it with jackstands. Remove the front wheel.

Click image to see an enlarged view

Fig. Fig. 1: The truck must be raised and the wheel must be removed for access to the brake rotor

  1. Remove the caliper assembly and attach it to the frame with a piece of wire without disconnecting the brake fluid hose.
  3. Remove the grease cap, cotter pin, locknut, thrust washer and outer wheel bearing.

Click image to see an enlarged view

Fig. Fig. 2: ALWAYS replace a used cotter pin with a new one

  1. Pull the hub and rotor assembly off the spindle.

To install:
  1. Slide the disc and hub assembly onto the spindle.
  3. Install the outer bearing, thrust washer and outer nut.
  5. Tighten the bearing adjusting nut down to 90 inch lbs. (10 Nm) while rotating the rotor and hub. Recheck the disc run out.
  7. Back off the adjusting nut to release all preload, and retighten the nut finger-tight.
  9. Install the locknut on the nut with one pair of slots in line with the cotter pin hole.
  11. Install a new cotter pin. NEVER use a old cotter pin.
  13. Clean and recoat the grease cap inside with bearing grease, not filling the cap, install the cap. Make sure the disc is completely clean of any dirt or grease. Use a suitable solvent.
  15. Install the caliper.


If the rotor is deeply scarred or has shallow cracks, it may be refinished on a disc brake rotor lathe. Also, if the lateral run-out exceeds 0.010 in. (0.25mm) within a 6 in. (152mm) radius when measured with a dial indicator, with the stylus 1 in. (25mm) in from the edge of the rotor, the rotor should be refinished or replaced.

A maximum of 0.020 in. (0.5mm) of material may be removed equally from each friction surface of the rotor. If the damage cannot be corrected when the rotor has been machined to the minimum thickness shown on the rotor, it should be replaced.

The finished braking surfaces of the rotor must be parallel within 0.007 in. (0.17mm) and lateral run-out must not be more than 0.003 in. (0.07mm) on the inboard surface in a 5 in. (127mm) radius.