Cars can make a lot of noise, but unusual or unexpected noises are often parts of your car trying to tell you that trouble is on the way. You rely on your car's brakes to bring your vehicle and its occupants to a safe stop, so it is particularly important to heed the warning signs of brake failure. While most people associate brake noises with the distinctive squeak of a worn-down pad, that's not the only sound that can originate from your braking system. Learning to recognize these sounds and what they mean can help you to avoid a dangerous brake failure in the future.
Squeals and Squeaks
Any time you hear your brakes making a squealing or squeaking sound, you can be sure that some form of metal-on-metal contact is occurring. In the case of brake pads worn beyond their safe limits, this contact is the result of metal wear strip becoming exposed and rubbing against the rotor. When you hear this noise on older pads, you know that a brake job is in your near future. If your car is equipped with brake wear sensors, you may also have a warning light illuminate on your dash once the pad has reached this point.
Surprisingly, squeals can also occur with fresh pads. A piece of metal called an anti-rattle clip usually prevents your brake pads from moving within the caliper brackets. If this part is installed improperly or if the metal surfaces are not lubricated, then the movement of the pads can result in squeaking. Although this will not impact your car's braking performance, it will continue to generate noise until fixed.
Loud and persistent grinding is usually the result of rotor damage caused by exceptionally worn pads. When your brake pads wear beyond their safe levels, the metal backing plates can potentially come into contact with the rotors. If the pads continue to wear down, the caliper itself may begin to rub against the surface of the brake disc. In either case, grinding indicates that your rotor is in contact with a hard surface and is likely being damaged. If you can hear grinding from your brakes, it is essential to have them serviced immediately.
Clunking or Knocking
If you hear a loud clunk or repeated knocks while braking, then there may be something loose in your caliper or you may have a suspension problem. Loose brake pads can sometimes cause light knocks or clunks accompanied by squeaking. If the pads are still good, then the solution is usually to replace the anti-rattle clip and fully tighten the caliper bolts. In many cases, however, clunking while braking may indicate an issue with your vehicle's control arm bushings or other suspension components. Since there is such a wide range of possible causes for noises of this type, it is usually a good idea to have your brakes serviced as soon as possible to rule out any potentially dangerous problems.
For more information, contact a mechanic that offers car brake services.