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Brake Noise

BRAKE NOISE

Some brake noise is normal and differences in loading, type of driving, or driving style can make a difference in brake wear on the same make and model. Depending on weather conditions, driving patterns and the local environment, brake noise may become more or less apparent. Verify all metal-to-metal contact areas between pads, pad guides, caliper and knuckles are clean and lubricated with a thin layer of high temperature silicone grease. Brake noise is caused by a "slip-stick" vibration of brake components. While intermittent brake noise may be normal, performing 3 to 4 aggressive stops may temporarily reduce or eliminate most brake squeal. If the noise persists and is consistently occurring, a brake dampening compound may be applied to the back of each pad. This allows parts to slide freely and not vibrate when moving relative to each other. Use Silicone Brake Lubricant, ACDelco P/N 88862181 (Canadian P/N 88862496) or equivalent.

The following noises are characteristics of all braking systems and are unavoidable. They may not indicate improper operation of the brake system.

Squeak/Squeal Noise:

- Occurs with front semi-metallic brake pads at medium speeds when light to medium pressure is applied to the brake pedal.

- Occasionally a noise may occur on rear brakes during the first few stops or with cold brakes and/or high humidity.

Grinding Noise:

- Common to rear brakes and some front disc brakes during initial stops after the vehicle has been parked overnight.

- Caused by corrosion on the metal surfaces during vehicle non-use. Usually disappears after a few stops.

Groan Noise:

A groan type noise may be heard when stopping quickly or moving forward slowly from a complete stop. This is normal. On vehicles equipped with ABS, a groan or moan type noise during hard braking applications or loose gravel, wet or icy road conditions is a normal function of the ABS activation.