Pontiac 18060242 Front Brake Rotor Assembly

Raise the car, support it with jack stands, and remove the wheel and tire assembly. Remove the brake caliper, and support with wire. Remove the dust cap and remove the cotter pin and the bearing retaining nut. Remove the outer wheel bearing and place it in a clean location. Remove the wheel bearing, hub, and disc assembly from the spindle. Installation is in the reverse order of removal. Check the disc for any obvious defects such as excessive rust, chipping, or deep scoring. Make sure there is no wheel bearing play by performing the wheel bearing adjustment procedure. Then, check the disc for run-out by installing a dial indicator on the caliper so that its feeler will contact the disc about one inch below its outer edge. Turn the disc and observe the run-out reading. If the reading exceeds 0.002 in. (0.05mm), replace the disc. Check the caliper thickness with a vernier caliper or other appropriate tool. Minimum thickness dimensions are cast into the disc. Adjust the wheel bearings.

Whenever the disc brake pads are inspected for wear, it is important to also check the condition of the disc (rotor) surfaces. Light scoring or grooving is normal, but deep grooves or severe erosion are not acceptable. Models from 1974 and earlier feature a single deep groove known as a 'squeal' groove, which should not be mistaken for damage. If vibration occurs during brake pedal application, disc runout may be the cause. To check for this, a dial gauge or feeler blades can be used between the disc and a fixed point, ensuring that the runout does not exceed 0.004 inches. Variations in disc thickness greater than 0.0005 inches can also lead to vibration during braking. Discs typically have wear limit and refinish thickness dimensions cast into them, and if a dealer cannot refinish a disc to meet specified tolerances, a new disc must be installed. When a brake drum is removed for lining inspection, it should be checked for cracks, scoring, or being out of round. An out-of-round drum can cause a pulsating feeling in the brake pedal during application, and the internal diameter should be measured at various points using an internal micrometer. Drums can be refinished internally as long as the wear and refinish sizes cast into them are not exceeded.

You can check the disc thickness with a micrometer. Make sure it does not go below the specified minimum thickness, which is cast into the disc.

Start by loosening the wheel lug nuts and raising the front of the vehicle on jack stands. Remove the wheel and then the brake caliper.

You can check the disc thickness with a micrometer. Make sure it does not go below the specified minimum thickness, which is cast into the disc.

You can check the disc thickness with a micrometer. Make sure it does not go below the specified minimum thickness, which is cast into the disc.

An out-of-round drum can cause a pulsating feeling in the brake pedal during application.

The rotor must be removed and taken to an automotive machine shop for resurfacing.