Last updated: November 26, 2021 at 10:37 am
When it comes to driving, not many things are more annoying (or embarrassing) than squeaky brakes. More often than not, it’s not anything serious and can be fixed with a little knowledge and persistent.
In this article, we’ll run through why your car brakes might be squeaking, and how to fix them. If you want to fix any other noises or learn more about car soundproofing, check out our car noise section.
Reasons Why Your Car Brakes Squeak
Your Car or the Brakes Are New
If you have a new car or a new set of brakes and they’re squeaking, it doesn’t necessarily indicate a problem. Sometimes new brakes need to bed in. Bedding in removes the surface of the brake pads and increases the amount of friction. The squeaking will stop when this process is complete.
Cheap Brake Pads
Cheap brake pads may look the same as more expensive ones, but their composition is entirely different. Cheaper brands include brass, copper, graphite, and steel shavings mixed with resin and when they wear down, it is these elements that can cause a squeak. Unfortunately, there is nothing you can do to remedy this unless you choose to replace them with a higher-end brand.
Worn Brake Pads
If your brake pads have become old and worn, they become too thin to be effective. When this happens, the squeaking noise can be due to the metal brake disk rubbing against the metal rim of the wheel.
If you notice the squeaking more on cold days, it may be that the cold is responsible. Cold temperatures can change the flexibility of the rubber. You might also notice the squeaking is worse in the morning. This is because moisture builds up on the brakes overnight, causing a thin layer of rust. When you use your brakes, this layer is removed, causing a squeaking sound. It might be annoying, but neither of these problems is something that you can fix.
You Carry Heavy Loads
If you regularly have a lot of passengers in your car or load it up with heavy items, then you may find your brakes squeak more. This is because it takes more energy to slow the car, and so your brakes will wear down more rapidly. This increased work leads to increased heat, which can cause the metal to swell which can also produce a squeaking sound.
Stones and Grit
As you drive, your tyres will pick up grit, stones, and mud. Small stones lodge in your brakes frequently, and you will likely not notice any change most of the time. If a larger stone gets lodged in your brakes, you will hear a squeaking sound when the brake calliper presses the stone deeper into the pad.
Seized Calliper Slider Pins
The slider pins are an essential part of your car’s brakes. They ensure that the pressure from the brake pads is applied evenly to the discs. If one seizes, the pressure will be uneven, and your pads will wear unevenly. If they both seize, then the brakes might be permanently in contact with the disc.
Glazed Brake Pads
If the brake pads are trapped against the discs, both can be exposed to extreme friction and heat. The heat causes glazing, which is when the brake pads crystallise and become hard. This reduces the friction and the braking ability of the pads.
7 Ways to Fix Squeaky Brakes
1. Grease Your Brake Pads
If your brakes are new, you might be able to fix the squeaking by greasing all the points of contact. You should remove the brake pads from their calipers and grease the back of the brake pad as well as any places where the calipers attach to the pad. Be very careful while doing this; the surface of the pads need to remain clean. Any grease would affect the effectiveness of the brakes. Once you’ve applied the grease, gently move the calipers, and listen to see if there are any squeaking noises. If there are, try applying a little more grease in that area.
- Synthetic grease for the braking system
- Covers very well and is resistant to road salt and water spray
Last update on 2022-01-17 at 10:08 / Images from Amazon Product Advertising API
2. Bed in Your Brakes
As explained above, new brakes may need to be bedded into both improve their effectiveness and stop the squeaking. It will remove the outer smoother layer of the brakes and improve their grip. You need to do this while driving, so consider safety first. Try the following process on a quiet road with few other road users to avoid potentially causing an accident.
Accelerate to around 60mph and then brake firmly until the car slows to around 10mph. If you do this between eight and ten times, the brakes will be bedded in, and the squeaking should stop.
3. Fit Shims
Some brands of brake pads come with shims already fitted. If not, you can get a set and either install them yourself or have a mechanic do it. Shims are made of metal or rubber, and they sit between the brake pad and disc, more info here. They minimise the amount of movement the brake pad can make and reduce vibrations which can prevent squeaking due to the pad and disc not connecting fully.
4. Replace the Brake Pads/Discs
Eventually, your brake pads and discs wear down. This happens more quickly if you carry lots of passengers or heavy loads as above. Once they wear to a certain point, there’s no option but to replace them.
If the brake pad has less than three-eighths of an inch thickness, they need to be replaced. In the case of brake disks, look for any deep groove or if the edge has a significant lip.
Brake pads and discs should be replaced as a set-in order to ensure your brakes are safe. You can get this done at any time if a mechanic confirms they are too worn, but they are often replaced as part of your car’s annual MOT and service. Brakes that are too worn would cause an MOT failure.
If your brakes look anything like above, there’s a good chance any squeak is because of rust buildup. Especially if you haven’t used your car for a while, the rust caused by moisture forms a much thicker layer. Once the rust reaches a certain thickness, it will no longer wear off through normal use. To see if this is causing the problem, buy a brake cleaning fluid and clean this disc until the rust is removed. If this doesn’t stop the squeaking, try some of the other solutions listed here.
6. Clean & Grease the Caliper Slider Pins
If you believe the calliper slider pins are seized, then as a first step, you should clean them thoroughly with a solvent. Once they are clean, apply grease to the pins and then make sure that they can move freely. The brakes get extremely hot, so make sure you choose a brand that is effective at high temperatures. If you’re still unable to move them, then they may need to be replaced. If you’re unsure, it’s best to consult a mechanic.
7. Sand the Brakes
If your brakes have become glazed, you can restore the surface on the brake pads and discs by sanding them down. Sand them just enough so that surfaces are rough again. You will normally need to pair this with a repair to the calipers, as explained above. Again, if in any doubt, you should consult a mechanic. Brakes are not an area you should work on unless you are confident you will complete the maintenance or repair correctly.
There are many reasons your brakes will squeak, and in the majority of cases, there isn’t a significant problem you need to fix. The squeaking noise may stop on its own when the brakes are bedded in or when the weather warms up. In other cases, you may need to replace your brake pads and discs because they’re worn or because they’re low quality.
Brakes are a vital safety feature in your car so never let them get so worn down they’re no longer effective. If you need help making any adjustments, then consult your mechanic or a qualified fitter and have them carry it out for you.