REMOVAL & INSTALLATION
- Use a siphon or clean turkey baster to remove about half of the brake fluid from the master cylinder. Or remove all of the fluid, clean the reservoir with an approved brake cleaner and a clean lint-free cloth and fill 1 / 2 full with fresh brake fluid.
- Raise and safely support the vehicle with jackstands.
- Remove the front tire and wheel assemblies.
- If necessary, remove the brake hose mounting bolts from the steering knuckle.
Regardless of their wear pattern, when brake pads are replaced on one side of the vehicle, they must also be replaced on the other side. It is advisable, however, to complete one side before beginning the other.
- Working on one brake caliper at a time, remove the lower brake caliper bolt and pivot the caliper up and out of the way.
- Remove the brake pads, shims and retainers.
- Inspect the brake pads, as outlined later in this section. If the pad thickness is less than the service requirement, replace them.
- Clean and check the brake rotor for cracks and uneven wear, or an excessive ridge on the outer circumference. Measure the brake rotor thickness with a micrometer and replace the rotor if the measured thickness is less than the minimum thickness specification stamped into the rotor. For more information, refer to the procedure in this section.
- Clean the caliper brackets, and lubricate the bracket sliding pins with a high temperature brake grease.
- Apply a light coat of an anti-seizing compound to the brake pad backing tabs and the slots the tabs are installed into on the brake caliper bracket.
- Make sure all the brake pad retainers and shims are properly and securely installed. If equipped with wear indicators, install the brake pad such that the wear indicator is at the top of the inside brake pad.
If the brake pads are being replaced, the brake caliper piston must be pressed back into the caliper body as follows:
- Clean the exposed portion of the brake caliper piston with an approved brake cleaner, and wipe off any residual debris using a clean lint-free cloth.
- Using a tool designed for retracting brake caliper pistons or a suitable C-clamp, press on the center of the brake piston using a slow, light, even pressure to press the piston into the caliper. If necessary, place a suitable sized socket in the center cavity of the piston to act as a spacer, or, use an old brake pad to lay across the piston.
Possible causes for a brake caliper piston to bind include:
- Install the brake pads.
- Pivot the caliper down to its installed position, then install the mounting bolts.
- Check the master cylinder brake reservoir fluid level and top off as necessary.
- Once the brake calipers are completely installed, press the brake pedal in short 2 inch (50mm) strokes until the brake pedal is firm. Avoid pressing the brake pedal more than 2 inches because the wear in the master cylinder bore could damage the internal seals. Depress and hold the brake several times to ensure they work.
- Carefully road test the vehicle. Allow approximately 200 miles (320km) of driving for new brake pads to fully seat.
You should check the brake pads every 6,000 miles (9,600km), any time the oil is changed or wheels are removed. Inspect both ends of the outer brake pad by looking in at each end of the caliper. These are the points at which the highest rate of wear normally occurs. Also, check the thickness on the inner brake pad to make sure it is not wearing prematurely. Some inboard pads have a thermal layer against the steel backing surface which is integrally molded with the pad. Do not confuse this extra layer with uneven inboard/outboard brake pad wear.
Look down through inspection hole in the top of the caliper to view the inner brake pad. Replace the pads whenever the thickness of any pad is worn within 0.030 in. (0.76mm) of the steel backing surface. For riveted brake pads, they must be replaced if the pad is worn to 0.030 (0.76mm) of any rivet head. The disc brake pads MUST be replaced in axle sets, for example, if you replace the driver's side front brake pads, you must also replace the passenger's side front brake pads. This will prevent uneven wear and other brake system problems.
- Remove the brake pads and observe their condition.
- Measure the thickness of the brake pad's lining material at the thinnest portion of the assembly. Do not include the pad's metal backing plate in the measurement.
- If you can't accurately determine the condition of the brake pads by visual inspection, you must remove the caliper, then remove the brake pads.