What causes squeaky brakes and how to fix them

Brakes can endure a lot of stress. Brake systems rely on friction to help slow down a vehicle, which causes wear. As you drive around (and if you park your vehicle outside), the parts of your brake system are exposed to moisture, temperature changes, salt, mud, and more. Between hard work and being subjected to these elements over time, it’s normal for your brake system to produce odd sounds. If your brakes squeal, grind or hiss, you could be experiencing one of the following problems.

Worn brake pads need to be replaced

Brakes pads often have a "wear indicator," explains AutoZone. As the pads wear down, the indicators begin to make a squealing noise so you’re aware it’s time to replace the brake pads. If the screeching or squealing sounds escalate to grinding noises, the pads may be completely worn away.

AutoZone also notes some newer vehicles have break wear sensors that give you a warning light on your vehicle’s dashboard when it’s time to replace squeaky brake pads.

Buildup of dust and debris

Dust and debris can accumulate quickly, and if you don’t have your car routinely serviced or cleaned, built-up material can lead to a squealing noise, according BRAKEmax. A trustworthy mechanic can clean your brakes, leaving them dust-free and noise-free if that is the only issue with the brake system.

Moisture or corrosion

Moisture from the elements (rain, snow, mud, etc.) or salt from the roads can lead to rust on parts of your brake system, like the rotors, explains the Vermont DMV. They advise that you can help stop rust from forming by simply using your brakes (continually driving your car), washing the underside of your car to remove salt and applying brake cleaner, as needed.

Eventually, rust buildup on your brake system can lead to strange noises, according to Wagner Brake. If the rust and corrosion get severe enough, braking performance can suffer, and parts might need to be replaced instead of simply being repaired or cleaned.

Lack of lubrication

Proper lubrication is essential for functioning brakes, according to PowerStop. If your car’s brakes are squeaking, brake lube could help in some instances. In fact, not only can applying brake lube to brake system components help stop the noise (if poor brake lubrication was the only issue), but it could also potentially increase these parts’ lifespan. Another common culprit of squeaky brakes is a poorly lubricated caliper that ends up sticking. The caliper encloses the brake pads and pistons, according to Goodyear Auto Service, and creates friction with the rotors to slow down the wheels. A caliper that sticks can reduce braking ability and may cause the car to "drag" as it rubs against the rotor, explains CarParts.com. Eventually, it can wear the brake pad down, leading to loud scraping sounds.

Poor installation or cheap parts

Cheap parts and improper installation methods can lead to squeaky brakes and other problems. For example, of the different types of brake pads, semi-metallic ones tend to cost less and are known to cause squeaking, according to AutoZone.

If you suspect any parts in your braking system are installed incorrectly or may be failing, bring your car to a mechanic as soon as possible.

Brakes need to ‘warm up’

Brake friction may produce hissing or grinding sounds when the brakes have accumulated dew and rust, explains Popular Mechanics. Rainy mornings can also cause brake pads to make noises. The sound should go away once the brake pads have scraped the rust off the disc.

However, if squealing or grinding noises continue, you should have the brakes checked by a professional.

Modern brake materials

Vehicles have gotten heavier over time due to upgraded parts and safety features, says Popular Mechanics. This has given rise to the use of metallic and ceramic materials on brake pads. These materials are better at slowing down heavier vehicles than their predecessors. But they also make for noisier brakes – which should not be concerning if your brake system is in good shape.

Squeaking or squealing brakes may not need major repairs or replacement, according to AAMCO, and as discussed above, some causes of brake noise resolve on their own. However, brake noises can also be a sign of or result of a more serious problem. So, if you experience unpleasant squealing or squeaking noises while braking, or notice a problem with your vehicle’s braking performance, take your car to a mechanic for closer inspection.

In addition to the tips shared above, upgrading to aftermarket brake pads is one way to silence harmless squeals, says Popular Mechanics. Many aftermarket parts are specially designed to reduce noise. Consult your local mechanic for options that work for your car.

Additionally, Popular Mechanics encourages trying anti-squeal adhesives. These are adhesives that bond well to metal. It requires removing and cleaning the pad and caliper. Then you would smear the adhesive on the piston. Only try this method if you're comfortable taking apart and reassembling the brake components.

Remember, serious brake issues should be addressed immediately by a professional mechanic.

As mentioned previously, modern brake pads may squeak due to the materials they’re made of or if moisture builds up on brake parts. This type of squeaking is usually harmless, says Popular Mechanics.

But new brake pads can also squeak because of a foreign object, explains Bockman's. Twigs, pinecones or rocks may get stuck between the brake pad and rotor, sometimes causing squeaking to occur without stepping on the pedal. If you suspect you have an object stuck in your brakes, bring your vehicle to a mechanic.

Usually, car insurance doesn't cover standard maintenance that comes with owning a car – which includes replacing worn brake pads.

But brake pads that are damaged in an accident may be covered. It depends on your policy. Comprehensive or collision coverage, for instance, could help cover you for roadway collisions, fallen trees, vandalized wheels or stolen wheels. Check your auto insurance declarations page or reach out to your insurer if you're unsure about what's covered or the specific coverages on your policy.