Rattle Noise from Front of Vehicle at Slow Speeds on Rough Surfaces when Brake Pedal is Not Applied (Install New Caliper Pin Bushing)

This bulletin is being revised to add additional models and model years. Please discard Corporate Bulletin Number 05-05-23-005 (Section 05 - Brakes).

Some customers may comment on a rattle noise coming from the front of the vehicle while driving at slow speeds over rough road surfaces when the brake pedal is not applied.

This condition may be caused by the interface of the front brake caliper guide pins and the front brake caliper bracket.

Verify the customer concern. To isolate the brake caliper guide pins as a potential source of the noise, apply the brakes when the noise is apparent. If the noise stops when the brakes are applied and comes back when the brakes are released, then the brake caliper guide pin bushings are the most likely source of the concern.

If the brake caliper guide pin bushings have been identified as the source of the noise, then replace the front brake caliper guide pin bushings on the lower pin on the brakes on both sides of the vehicle. Refer to the service procedure in this bulletin.

Caution: Avoid taking the following actions when you service wheel brake parts:

Caution: Brake fluid may irritate eyes and skin. In case of contact, take the following actions:

Removal Procedure

1. Raise and support the vehicle.

•	For Chevrolet Equinox, refer to "Lifting and Jacking the Vehicle" in General Information (SI Document ID# 1644943).

•	For Pontiac Torrent, refer to "Lifting and Jacking the Vehicle" in General Information (SI Document ID# 1644943).

•	For Saturn VUE, refer to "Lifting and Jacking the Vehicle" in General Information (SI Document ID# 995301).

2. Remove the tire and wheel assembly. Refer to "Tire and Wheel Removal and Installation" in Tires and Wheels (SI Document ID# 1219741).
3. Install and firmly hand tighten 2 wheel nuts to opposite wheel studs in order to retain the rotor to the hub.
4. Install a large C-clamp over the body of the brake caliper with the C-clamp ends against the rear of the caliper body and against the outboard brake pad.
5. Tighten the C-clamp evenly until the caliper piston is compressed into the caliper bore enough to allow the caliper to slide past the brake rotor.
6. Remove the C-clamp from the caliper.



7. Remove the brake caliper lower guide pin bolt.




Notice: Support the brake caliper with heavy mechanic's wire, or equivalent, whenever it is separated from its mount and the hydraulic flexible brake hose is still connected. Failure to support the caliper in this manner will cause the flexible brake hose to bear the weight of the caliper, which may cause damage to the brake hose and in turn may cause a brake fluid leak.

8. Without disconnecting the hydraulic brake flexible hose, pivot the caliper upward and secure the caliper with heavy mechanics wire, or equivalent.



9. Remove the lower caliper pin taking care not to damage the pin boot.



10. Remove the rubber bushing from the caliper pin.
11. Clean the pin and install a new bushing.
12. Lubricate the caliper pin and bushing assembly with a light coat of high temperature silicone brake lubricant and install in the caliper bracket.
13. Remove the support and rotate the brake caliper into position over the disc brake pads and to the caliper mounting bracket.
14. Repeat Steps 1-13 on opposite side brake assembly.

Installation Procedure

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.

1. Install the lower brake caliper guide pin bolt.

Tighten
Tighten the bolt to 44 N·m (32 lb ft).

2. Remove the wheel nuts retaining the brake rotor to the hub.
3. Install the tire and wheel assembly. Refer to "Tire and Wheel Removal and Installation" in Tires and Wheels (SI Document ID# 1219741).
4. Repeat Steps 1-3 on opposite side brake assembly.
5. Lower the vehicle.
6. With the engine OFF, gradually apply the brake pedal approximately 2/3 of its travel distance.
7. Slowly release the brake pedal.
8. Wait 15 seconds, then gradually apply the brake pedal approximately 2/3 of its travel distance again until a firm brake pedal apply is obtained. This will properly seat the brake caliper pistons and brake pads.

For vehicles repaired under warranty, use: