Disassembly Procedure
Important:
• Replace all the components included in the repair kits used to
service this brake caliper. • Lubricate the rubber parts with clean brake fluid to make assembly
easier. • If any hydraulic component is removed or disconnected, it may
be necessary to bleed all or part of the brake system. • Replace the brake pads in axle sets only. • The torque values specified are for dry, unlubricated fasteners. • Perform the service operations on a clean bench, free from all
mineral oil materials.
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.
- Remove the brake caliper from the vehicle. Refer to Front Brake Caliper Replacement .
- Remove the brake caliper pistons from the caliper bore by directing low pressure compressed air into the caliper bore through the fluid inlet hole.
- Remove the piston boots (2).
- Remove the piston seals (1).
- Remove the brake caliper bleed screw cap.
- Remove the brake caliper bleed screw (1).
- Inspect the brake caliper bores and piston seal grooves for scoring and corrosion. If badly scored or corroded around the piston seal area, replace the brake caliper housing.
- Inspect the brake caliper mounting bracket guide surfaces for corrosion and wear. Remove and replace the brake caliper mounting bracket if necessary.
- Clean all the residue from the brake pad guiding surfaces on the brake caliper housing and the brake caliper mounting bracket.
- Clean all the parts not included in the repair kit with denatured alcohol.
- Dry all the parts with filtered unlubricated compressed air.
- Blow out all passages in the brake caliper housing and the brake caliper bleeder valve.
- 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.
Important: Do not use abrasives to clean the brake caliper pistons.
Assembly Procedure
- Install the brake caliper bleed screw (1).
- Install the brake caliper bleed screw cap.
- 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 new seals (1) into the brake caliper bore seal grooves.
- Make sure the seals are not twisted.
- Lubricate the brake caliper bores and the pistons with brake fluid.
- Install the boot (2) and piston (3).
- Install the brake caliper to the vehicle. Refer to Front Brake Caliper Replacement .
Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.
Tighten
Tighten the brake caliper bleed screw to 12 N·m (106 lb in).
| 7.1. | Install the boot over the end of the piston so that the fold will face toward the brake caliper housing piston bore opening. |
| 7.2. | Seat the boot into the brake caliper bore groove and slide the piston into the brake caliper bore. |
| 7.3. | Push down the piston to the bottom of the brake caliper bore. |
| 7.4. | Make sure the boot is properly seated into the piston groove and into the groove in the brake caliper bore. |
| 7.5. | Repeat Steps 5 and 6 for the remaining piston. |
