- Remove the front brake
caliper from the vehicle. Refer to
Front Brake Caliper Replacement
.
Caution: Do not place your fingers in front of the piston in order
to catch or protect the piston while applying compressed air. This could result
in serious injury.
Notice: Use clean cloths to pad interior of caliper housing during piston removal.
Use just enough air to ease the pistons out of the bores. If the pistons are
blown out, even with the padding provided, it may be damaged.
- Remove the brake caliper pistons from the caliper bore by directing
low pressure compressed air into the caliper bore through the fluid inlet
hole.
- Using a small wooden or
plastic tool, remove the piston dust boot seals from the seal counterbores
in the caliper and discard the boot seals.
- Using a small wooden or plastic tool, remove the piston seals
from the caliper bores and discard the piston seals.
- Remove the bleeder valve and cap from the caliper.
Important: Do not use abrasives to clean the brake caliper pistons.
- Clean the brake caliper piston bores and seal counterbores, and the
caliper pistons with denatured alcohol, or equivalent.
- Dry the caliper piston bores and counterbores, and the pistons
with non-lubricated, filtered air.
- Inspect the caliper bores for cracks, scoring, pitting, excessive
rust, and/or excessive corrosion.
- If light rust or light corrosion are present in the caliper bores,
attempt to remove the imperfection with a fine emery paper. If the imperfection
cannot be removed, replace the caliper assembly.
- If cracks, scoring, pitting, excessive rust, and/or excessive
corrosion are present in the caliper bores, replace the caliper assembly.
- Inspect the caliper pistons for cracks, scoring, and/or damage
to the chrome plating. Replace the caliper pistons if any of these conditions
exist.
- Lubricate the new piston seals with Delco Supreme 11®
(GM P/N 12377967) or equivalent DOT-3 brake fluid from a clean,
sealed brake fluid container.
- Install the lubricated, new piston seals into the caliper bores.
- Install the new piston
dust boot seal over the piston.
- Install the caliper pistons into the caliper bores.
15.1. | Install the boots over the ends of the pistons so that the fold
will face toward the brake caliper housing piston bore openings. |
15.2. | Seat the boots into the brake caliper bore grooves and slide the
pistons into the brake caliper bores. |
15.3. | Push the pistons down to the bottom of the brake caliper bores. |
15.4. | Make sure the boots are properly seated into the piston grooves
and into the groove in the brake caliper bores. |
- Install the bleeder valve and cap to the caliper and tighten securely.
- Install the caliper to the vehicle. Refer to
Front Brake Caliper Replacement
.