When Brake Calipers Go Bad

In general, brake pads and rotors wear out and need replacement far more often than calipers. A leading cause for damaged calipers, however, stems from driving a vehicle on worn-out pads or warped rotors. Both prevent the system from dissipating the heat of friction, as they’re designed to do, which can damage the calipers.

If the pads fail to insulate the caliper from excessive heat, the piston can be damaged or the heat can be passed through the piston to the brake fluid, which can cause it to degrade. The latter can result in brake failure.

A damaged piston, or one that is simply corroded, may get stuck in one position. If it sticks in the retracted position, that wheel will lose braking ability. If it sticks in the engaged position, the wheel will brake continuously until freed.

How to Tell That a Caliper Has Failed

With a retracted piston, the car may pull toward the side of the car with operating brakes when they are engaged. You may also notice that braking distance increases. Conversely, an engaged piston will cause the car to pull toward the engaged brake when driving. (Note: A stuck caliper can cause pulling, but there are many other possible causes as well.) Excess heat will be present, and the brake pad will quickly wear down. Any of these symptoms indicate immediate need for service.

Another sign of caliper failure could include leaking brake fluid, as a damaged piston may no longer seal completely. If enough fluid escapes from the system, the warning light on the dashboard will call your attention to it. If you check your pad wear regularly, you may note uneven wear on the pads, comparing one side of the rotor to the other, or even left wheel to right wheel. If the pads show uneven wear, check the caliper function. And yet another sign of a seized caliper is excessive brake dust on one wheel compared to the other.