A Kia that is on one of our lifts.

Brakes grinding? Why is that?

In Brakes by HomeTowne Auto Repair & Tire

Have you been hearing an unpleasant sound as you’re slowing down? It may be your brakes grinding.

A grinding noise while braking could mean that the brake pads have become worn and their plates and the brake rotors are rubbing together.

Grinding is one of several symptoms that your vehicle is in need of brake repair. A large amount of brake dust can be another indicator that the brakes are ready to be replaced.

Per state inspection guidelines, brake pads should be at least 2/32 of an inch. Depending on the manufacturer’s recommendations, we may suggest changing them sooner.

Brake pads are one of the items our technicians check during courtesy inspections.

What does it mean if you notice a grinding noise when braking, but the pads are fine?

A symptom that can seem like brakes grinding at low speed could actually be the anti-lock braking system (ABS) engaging incorrectly. This can be due to an ABS wheel speed sensor or a problem with a hub bearing or wheel bearing causing the system to engage when it’s not supposed to.

What can cause brakes grinding noise other than normal pad and rotor wear?

If you notice a grinding sound, it may be that the pads and rotors are wearing unevenly or prematurely because of the wheel bearings. Whether they have the normal tapered bearing or a hub bearing setup, if the bearings are worn and are allowing the wheel to move back and forth it can create a different angle of pressure on the rotor and brake pads. That may lead them to wear out faster in one spot. You do want to get your vehicle checked out by a nearby auto repair shop to not only take care of the symptom but also the root cause.

Brakes grinding when stopping may be the result of rust building up on the rotors. This could just be from sitting for a while without driving the vehicle. If it’s not too bad, it will normally go away after the first two or three times you hit the brakes when driving down the road. The issue could also be caused by the type of metal the rotors are made out of and the way the pads are manufactured. It may result in irregular grooves and limited pad contact, which would allow rust to build up and noise to occur whenever you hit the brake pedal.

A brake rotor.

Why should you bring your car into a local repair shop when you hear a grinding noise?

Brakes could cause a grinding noise when there is a mechanical problem with the brake caliper, the hardware, or the caliper bracket. We have seen where sometimes the brake caliper hardware dislodges and gets caught on the rotor, producing a grinding sound. Bolts may be missing from the caliper bracket, causing the whole caliper assembly to move when pressing the brake. It could even be that the brake disc caliper has seized so it’s not sliding back and forth. The piston pushing the inboard pad is another possible issue. That can not only lead to rust build up on one side of the rotor, it can cause the inboard pad to wear down much faster. So if you look at the brakes through the wheel, the outboard pad will look fine but the inboard pad will be metal to metal. That’s why it’s a good idea to have your car checked at a local auto repair shop.

HomeTowne Auto Repair & Tire is an authorized Michelin and BFGoodrich tire dealer located in Woodbridge, Virginia. Automotive repair services are performed on all makes and models, including oil changes, brakes, alignments, inspections, and computer engine diagnostics.