What Causes Brakes to Squeak?

Squeaky brakes are the bane of many vehicle owners. There is nothing more irritating than a vehicle with noisy, squeaky brakes. Although rarely serious, squeaky brakes are often times a sign of some type of brake dysfunction.

Brake Dust

  • As brake pads wear, they shed small brake dust particles--particles that can coat the surface of a spinning brake rotor and lead to brake squeaking. The squeak occurs when the brake calipers are activated and they squeeze against the slippery, dust-coated brake rotor.

Vibrating Brake Pads

  • Brake pads that vibrate or shake during braking can lead to uneven pressure being applied to a spinning brake rotor, a condition that can cause reduced braking power as well as brake squeaking and grinding.

Dysfunctional Brake Rotors

  • Brake rotors are designed with smooth, flat surfaces that are easily grasped and held by brake calipers. Brake rotors that become rough, pitted or malformed create an uneven surface for brake pads to grasp onto, a condition that can lead to squeaky brakes.

Worn Brake Pads

  • Brake pads are made with built-in wear indicators, which are small metal strips embedded into the brake pad material. When brake shoes wear to the point that these wear indicators become exposed and rub against the spinning brake rotor, squeaky brakes are the result.

Dysfunctional Brake Calipers

  • Brake calipers are responsible for squeezing brake shoes tightly against brake rotors, a process which leads to vehicle braking. Brake calipers that are dysfunctional in some way can cause uneven brake shoe application, a condition that can lead to squeaky brakes.