Brake Wear Indicator: What That High-Pitched Squeal Is Telling You

Your car makes a high-pitched squeal, sometimes even when you are not pressing the brake. It may go quiet when you do press the brake. This sound is often not a problem by itself. It’s a built-in warning that your brake pads are almost worn out.

What is a brake wear indicator?

Many brake pads have a small metal tab attached to them. When the pad gets thin, the tab starts to touch the rotor. That makes a squeal on purpose, so you know it’s time for new pads before they wear down to metal.

Some cars, especially many European models and newer vehicles, use an electronic sensor instead. When the pad gets thin, the sensor turns on a brake pad warning light on your dashboard.

How to tell it’s the wear indicator

• The squeal is high-pitched, like a chirp or whistle.
• It often happens while driving, and may change or stop when you press the brake.
• It comes from one wheel, usually a front wheel.
• It started slowly and has been getting more frequent.

If the noise is a deep grinding sound instead, the pads may already be gone. Read grinding noise when braking.

How much time do you have?

When the wear indicator starts squealing, there is usually a little pad material left. That’s the point of the warning. But it’s not a lot. Plan to get your brakes checked within the next couple of weeks. If you wait too long, the squeal turns into grinding and the repair gets more expensive.

Other reasons brakes squeal

Not every squeal is a wear indicator. Brakes can also squeal because of:

• Moisture or light rust in the morning (goes away after a few stops)
• Dust and dirt between the pad and rotor
• Missing or dry grease on the brake hardware
• Hard pad material, like some semi-metallic pads

If your pads look fine but still squeal, see squeaky brakes but pads look fine.

What about the brake pad warning light?

If your car has electronic sensors and the brake pad light comes on, your pads are low. When the pads are replaced, the sensor usually needs to be replaced too, because it wears through when it does its job. A red brake warning light can also mean low brake fluid or a parking brake problem, so always get it checked.

Hearing a squeal? Let us check it for free

President Tire & Wheels offers a free brake inspection at 632 Colby Drive, Waterloo. If you need new parts, brake pads and rotors start at $350 per axle with a 1-year warranty, or $499 per axle with a 2-year warranty (most sedans).

Get a free brake quote, see our brake service page, or call (226) 698-1667. Serving Waterloo, Kitchener and Cambridge.