Close

Signs Your Brake Pads Are Worn, and What to Do About It

Mia Bevacqua
May 8, 2018

Copyright © 2018 RepairPal Inc. All Rights Reserved - Brake Pads 2

Image displays the differences between new (top) and worn (bottom) brake pads.

Signs of worn brake pads

Your brakes are the most important safety feature on your car. If you hear or experience any of the following symptoms of brake pad problems, get them checked out right away.

Noise when braking: The most common symptom associated with worn brake pads is noise. Most brake pads come with a steel wear indicator that produces a loud, high-pitched noise when the pad’s friction material is almost gone. You will hear this when you use the brakes. In some cases, the friction material used in low-quality brakes can also create a squealing noise. Pads that are ground down to the backing plate will cause a metallic grinding sound and, typically, a vibration. 

Low brake fluid level: If the pads are extremely worn, the brake caliper piston may fully extend in an effort to push the pads against the rotor. This moves the brake fluid from the reservoir to the caliper, creating a low level.

Warning lights are on: Many high-end vehicles have an electronic brake wear sensor instead of the noisy wear indicator. When the pads wear too much, a light illuminates on the dash, indicating it’s time for maintenance. A low brake fluid level, caused by excessively worn pads, may also trigger the brake warning light.

You have to push harder on the brake pedal: Worn brake pads can cause excessive pedal effort. This is not as common in today’s braking systems, but it still happens occasionally.

Your brakes feel grabby: Pads that are worn unevenly, contaminated or glazed can result in grabby brakes. They can also cause the vehicle to pull to one side when the brakes are applied.

You feel a pulsation when braking: pulsation in the brake pedal or steering wheel while braking, is usually caused by warped rotors. But brake pads that are worn unevenly can have the same effect. Instead of applying seamlessly, the irregular pads bounce up and down on the rotor, creating a vibration.

» MORE: Get an estimate for your brake pad replacement

What brake pads do

There are two brake pads at each brake rotor — one on either side. When the brakes are applied, the pads squeeze the rotor. This brings the vehicle to a halt. The basic brake pad design uses friction material attached to a metal backing pad. A wear indicator may also be affixed to the pad, to signal when it’s time for new pads. What differentiates one kind of pad from another is its friction material. There are three common brake pad types in use today.

Organic

This type of brake pad is typically the least expensive, but suffers from brake fade under heavy load. Brake fade is the the result of the pad losing friction, or stopping power, when it becomes hot, requiring extra pedal effort from the driver. Organic brake pads replaced asbestos pads, which were a health hazard to both mechanics and the public. Non-asbestos organic (NAO) brake pads are made of a combination of fibers and other material, and are bound together with resin. While this construction produces minimal noise, it also wears out quickly and doesn’t perform as well as other material types. 

Metallic

Also known as semi-metallic, these brake pads are made from as much as 70% metal, including materials such as copper, iron and steel. Metallic pads perform better than their organic counterparts, and they last longer, too. Unfortunately, they can also be noisy and create a lot of dust. In most cases, the price of metallic pads is somewhere between that of organic and ceramic. 

Ceramic

When it comes to brake pads, the old saying “you get what you pay for” holds true. While they cost more, ceramic pads typically perform better and last longer than other pad types. Plus, they run more quietly. As the name implies, this type of pad is made from ceramic material, usually combined with metallic alloys. Both metallic and ceramic pads wear out the brake rotor as well as the pad itself, but the significant improvement in stopping power is well worth the additional cost.

Get it diagnosed by a professional
 

How to fix a worn brake pad

If you’re having a problem with your brakes, it’s not safe to drive your car. It needs attention immediately. Worn or damaged brake pads should be replaced as soon as possible. In most cases, a brake job is a relatively easy task to perform. But because there’s so much riding on the performance of your brakes, replacement should be left to a professional.

Before spending time and money to replace the brake pads, a thorough diagnosis should be performed. At the same time, the rotors should be measured to see if they can be reused. When the brake pads are replaced, the rotors should also be either resurfaced or replaced at the same time.

When replacing brake pads, it is important to replace the corresponding pads on the other side of the vehicle. This will ensure the braking power is even and predictable.

To replace the brake pads, the mechanic will first lift the car and remove the wheels in question. The brake calipers and rotors are then removed and checked. The new pads are installed, and the rotors, calipers and wheels are replaced, if there are no further repairs needed.

Note: Removing the rotors on certain suspension types, and on some front-wheel drive or four-wheel drive vehicles, can be a significant task. For example, inboard rear discs are not inside the wheel but next to the differential under the car, and take much more time to repair. 

Mia Bevacqua

About the Author

Mia Bevacqua is an automotive expert with ASE Master, L1, L2 and L3 Advanced Level Specialist certification. With 13-plus years of experience in the field, she applies her skills toward writing, consulting and automotive software engineering.

No comments yet...

Sign in to comment

Related Questions

See what others have asked about this, or visit the Questions page to ask your own question.
Why the second half of a brake pad will wear away more quickly than the first? isn't it the same material? thank you ...
All four of my brake pads were replaced, but my car is still making a loud squeaking noise when i brake. why is this?