Stuck caliper

Hi,

Is it the caliper piston that is sticking?

I need you to try something. Lift the wheel off the ground and cause the caliper to lock so you can't turn the wheel. Then, open the bleeder on the rear of the caliper to see if it releases. If it doesn't, then we either have a caliper piston issue or the slide pins are frozen. If it does release, the rubber brake hose is the likely cause.

I attached a pic of a caliper below and highlighted the bleeder. That is what I want you to loosen to see if the wheel becomes free. Once you make that determination, close the bleeder.

Let me know what you find or if you have other questions. I want to do it this way simply I need to determine what is causing it to lock.

Take care and God Bless,

Joe

Hi,

If the piston is stuck, we have two choices. You can rebuild it or replace it. The cost and time to rebuild it will likely be higher than purchasing a remanufactured one from a parts store.

However, I will provide directions for both replacement and overhaul. The attached pics correlate with the directions.

__________________________________________

Overhaul:

2004 Pontiac Grand AM V6-3.4L VIN E
Front
Vehicle Brakes and Traction Control Hydraulic System Brake Caliper Service and Repair Procedures Brake Caliper - Overhaul Front
FRONT
Brake Caliper Overhaul - Front

Removal Procedure

Caution: Refer to Brake Fluid Irritant Caution.
See: Brakes and Traction Control > Technician Safety Information > Brake Fluid Irritant Caution

pic 1

1. Remove the front brake caliper from the vehicle.
2. Remove the brake caliper piston from the caliper bore by directing low pressure compressed air into the caliper bore through the fluid inlet hole.

Pic 2

3. Using a small wooden or plastic tool, remove the piston dust boot seal (2) from the seal counterbore in the caliper (1) and discard the boot seal.
4. Using a small wooden or plastic tool, remove the piston seal (4) from the caliper bore and discard the piston seal.
5. Remove the bleeder valve (5) and cap (6) from the caliper (1).

Important:Do not use abrasives to clean the brake caliper piston.

6. Clean the brake caliper piston bore and seal counterbore, and the caliper piston with denatured alcohol, or equivalent.
7. Dry the caliper piston bore and counterbore, and the piston with non-lubricated, filtered air.
8. Inspect the caliper bore for cracks, scoring, pitting, excessive rust, and/or excessive corrosion.
9. If light rust or light corrosion are present in the caliper bore, attempt to remove the imperfection with a fine emery paper. If the imperfection cannot be removed, replace the caliper assembly.
10. If cracks, scoring, pitting, excessive rust, and/or excessive corrosion are present in the caliper bore, replace the caliper assembly.
11. Inspect the caliper piston for cracks, scoring, and/or damage to the chrome plating. Replace the caliper piston if any of these conditions exist.

Installation Procedure

pic 3

1. Lubricate the new piston seal (4) with Delco Supreme 11(R) GM P/N 12377967 (Canadian P/N 992667) or equivalent DOT-3 brake fluid from a clean, sealed brake fluid container.
2. Install the lubricated, new piston seal (4), into the caliper bore.
3. Install the caliper piston (3) into the caliper bore.
4. Install the new caliper dust boot seal (2)
5. Install the bleeder valve (5) and cap (6) to the caliper and tighten the valve securely.
6. Install the front brake caliper to the vehicle.

_____________________________________

Replace

2004 Pontiac Grand AM V6-3.4L VIN E
Front
Vehicle Brakes and Traction Control Hydraulic System Brake Caliper Service and Repair Procedures Brake Caliper - Replacement Front
FRONT
Brake Caliper Replacement- Front

Removal Procedure

Caution: Refer to Brake Fluid Irritant Caution.
See: Brakes and Traction Control > Technician Safety Information > Brake Fluid Irritant Caution

Notice: Refer to Brake Fluid Effects on Paint and Electrical Components Notice.
See: Brakes and Traction Control > Vehicle Damage Warnings > Brake Fluid Effects on Paint and Electrical Components Notice

pic 4

1. Raise the vehicle. Refer to Vehicle Lifting.
See: Vehicle Lifting > Procedures > Lifting and Jacking the Vehicle

2. Remove the tire and wheel assembly.
3. Hand tighten 2 wheel lug nuts to retain the rotor to the hub.
4. Push the piston into the caliper bore in order to provide clearance between the linings and the rotor:
4.1. Install a large C-clamp over the top of the caliper housing and against the back of the outboard pad.
4.2. Slowly tighten the C-clamp until the piston is pushed into the caliper bore far enough to slide the caliper assembly off the rotor.

Pic 5

5. Remove the brake hose bolt (1) discard the gaskets (3).
6. Plug the caliper housing and brake hose in order to prevent fluid loss and contamination.

Pic 6

7. Remove the caliper bolts (2).
8. Remove the caliper from the rotor and the caliper bracket (3).

Installation Procedure

pic 7

1. Lubricate the caliper bolts with GM P/N 18010908 high temperature silicone brake lubricant or equivalent. Do not lubricate the threads.
2. Install the caliper (3) to the caliper bracket (1).

Notice: Refer to Fastener Notice in Service Precautions.
See: Brakes and Traction Control > Vehicle Damage Warnings > Fastener Notice

3. Install the caliper mounting bolts (2) to the caliper bracket (1).
- Tighten the 2 caliper mounting bolts to 31 Nm (23 lb ft).

Pic 8

4. Install the brake hose bolt (1) with new gaskets (3) to the brake hose inlet fitting (2).
5. Install the brake hose with the brake hose bolt (1) to the brake caliper.
- Tighten the inlet fitting boll to 50 Nm (23 lb ft).

6. Remove the 2 hand tightened wheel lug juts retaining the rotor to the hub.
7. Install the wheel and tire assembly.
8. Lower the vehicle.
9. Fill the master cylinder to the proper level with clean brake fluid.
10. Bleed the entire brake system.
11. Inspect the hydraulic brake system for leaks.

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I strongly recommend replacing the slide pins and brake hardware.

Let me know if this helps or if you have other questions.

Take care and God bless,

Joe