What Are the Causes of Brake Chatter?by David Dunning
In a motor vehicle, when the brake pedal is depressed, brake fluid is sent to the brake calipers, which straddle the disc in a disc-brake assembly. This creates hydraulic pressure, which, in turn, squeezes the brake rotor in between the brake pads.
Symptoms of brake chatter can range from the grabbing of the brakes and slight vibration at low speeds to more violent shaking.
Brake chatter can occur if the brake rotor is warped, if the lining of the brake pads is contaminated with oil or brake fluid or if the brake linings move slightly.
If the lining of the brake pads becomes contaminated, chatter may result from the brake pads vibrating as they grab and release the surface of the rotor. If this is the case, the problem can be solved by replacing the contaminated pads.
The brake rotor can become warped, or develop an uneven surface, as a result of everyday wear and tear. Warping can also be caused by expansion and contraction of the rotor, or if brake pads are severely worn.