Why brakes squeak

Brake pads make squeaking when braking, but the true cause of these unpleasant sounds is not always just them. There are six main reasons why brakes squeak, and to find out it is enough to check the wear of pads, discs and the condition of calipers.

With a standard car tool kit, find out why the squeaky brakes occur.

Causes of squeaky brake pads

The easiest answer to the question of why the brakes squeak is wear and tear on the pads. But often even new brake pads can squeak. In that case, the cause of squeaking may be brake discs, hub bearings, improperly selected brake pads, ingress of dust, dirt, or moisture into the braking system.

Top 5 reasons your brakes make noise: video

Therefore, let's consider each of the causes separately, why this happens, and then how to fix the problem.

Brake pads

In 90% of cases, it is the front brake pads that squeak when the brake pedal is depressed. After all, during braking the weight of the car is transferred forward, and, accordingly, the front pads are experiencing a greater load than the rear ones. Therefore it is necessary to start checking them.

At the maximum allowable wear will squeak the mechanical wear sensor (if there is an electronic you will see a notice on the panel of the need to replace the pads). But the squeak can also produce almost still new brake pads. There are a number of reasons for this.

The first one is probably the installation of non-original pads of the worst quality, or simply different in their hardness in relation to the brake disc. The second reason for the squeal may be the lack of grooves on the friction surface. These grooves drain the brake dust and avoid resonance when they are actuated. Also, not all pads may have anti-squeak plates that allow heat to be removed and prevent the pad from vibrating in its seating position.

Caliper and Guides

The caliper and the guides need to be lubricated

The piston and guides, which are the moving parts of the caliper, can also cause the pads to malfunction. If dirt gets inside, they can get rusty, jam, and move unevenly. Thereby incorrectly press the pads or do not return to their original position, which will undoubtedly cause a squeak or squeak. Also, in addition to the sound, such a malfunction will affect the accelerated wear of the brake system. You can detect this malfunction by the appearance of the brake disc (there will be a darkening from the high temperature as a result of overheating).

Brake discs

During braking, the surface of the disc heats up due to friction and when it reaches a critical temperature, depending on the disc and the metal it is made of, the disc may emit an unpleasant noise similar to a squeak and/or squeak. Older, non-vented discs are especially prone to this phenomenon. They do not have holes for heat dissipation, so they heat up faster and hold their temperature longer.

Also, the squeaking will occur during the lapping of the old disc to the new pads or even an entirely new complete set. After a while the problem usually goes away (50 — 100 km), but if the disc critical wear sounds squeak or wear can be removed only by replacing them.

Hub Bearing

Checking the hub bearing

In a worn hub bearing, the squeak will be produced by a disintegrated cage with balls. But, as a rule, with such a problem, the noise comes from the wheel constantly when driving. Driving with a defective hub is dangerous, as there is a risk of the wheel jamming at speed, which can lead to an accident!

External factors

If a squeak or squeal sounds after driving in puddles, mud, after a long stop in a wet, sandy road or in frosty weather, it is only temporary. After 5 to 10 minutes of driving in normal conditions, the squeaking stops.

How to eliminate squeaking when braking?

The method of removing the squeak or squeak of the brakes will depend on the cause. Most often, especially on cars with high mileage, their owners forget to make replacement, and pads in the process of braking squeak due to wear (lifetime of front pads is 35 000 — 55 000 km, rear can go up to 80 thousand km).

How to fix squeaky disk brakes and drum brakes: video

Start by removing the caliper and inspecting the pads and discs, then move on to inspect the caliper parts. You need to check the condition of the dust cover, its integrity. If it gets into dirt, it is necessary to carry out its revision and replace. Do not forget to check the free movement of the guides in the caliper. Traces of rust and oxidation are removed with a special grease for calipers.

If you have problems with pads — change not new or better ones, install anti-squeak plates, clean the seating and fixing clips from dirt and rust (according to the instructions such places are also treated with copper grease).

Disc problems can also be corrected in several ways. The easiest and most effective is to replace and install a vented disc (the part is selected from a catalog). If the disc has grooves, but the thickness allows, it can be turned (a special machine is used). An indirect sign that the disc is «bent» is the situation when the car brakes jerkily. Brake discs, as well as pads, also have their service life, the wear is determined by the condition of the surface as well as by the mark on the end face.

FAQ

• How do I get my brakes to stop squeaking?

  If your brakes are new, you should grease the contact points to stop squeaking. In other cases — check the caliper and guides.

• Is it OK to drive with squeaky brakes?

  Long riding with squeaking brakes can cause serious damage to brake discs. Also there will be a huge risk of brake failure right along the way.

• How much does it cost to fix squeaky brakes?

  Inspection of braking system will cost near $88 — 110. You can pay approximately $300 for brake pads and labor. To change rotors you need over $400.