The braking system is a crucial part of a car, helping it slow down and stop. Therefore, you should fix any symptom of a developing problem, like noise. When there are grinding noises when the vehicle brakes, the causes must be determined and fixed soonest.
So, what are the reasons for grinding noise when braking? Worn brake pads, warped rotors, and lack of lubrication are some reasons behind the grinding noise braking. Also, debris between brake pads and rotors and loose components, especially in the caliper, can be the reasons, too. Diagnose the issues further to determine the exact cause.
Most solutions to the issues mentioned are simple and doable without professional assistance. Read on for a detailed list of causes and how to solve them.
What Causes Grinding Noise When Braking? Diagnosing and Fixing Discussed
Grinding noises only when the vehicle brakes point to an issue with the braking system. The following list contains various parts of the brake system that can cause grinding noises when the vehicle brakes.
Brake pads stop your vehicle when you press the brake pedal. These parts interact with the disc or rotor on the car’s wheels, slowing it.
However, this generates much heat through friction, which causes the brake pads’ friction surfaces facing the car’s rotor wear. On average, by 50,000 miles, the brake pads are already worn out and need replacing. When they wear, you’re more likely to hear the grinding noises when braking.
You need to access the brake pads to confirm whether they are behind the grinding noises when braking. Generally, to access the brake pads, you’ll need to follow the steps below;
- Step 1. Lift the vehicle, then remove the wheel
- Step 2. Remove the brake caliper after removing the bolts and pins holding it in place.
- Step 3. Observe the brake pads if it’s worn or broken due to thermal fatigue.
The brake pad is worn if the friction part is thin ( 3 mm or less) or there’s more gap between the brake pad and the rotor. The diagnosis will be easier if your vehicle is fitted with a brake pad wear sensor.
The solution to worn brake pads is to replace them with a new matching pair. Also, it’s best to replace the brake pads in all four wheels at once to prevent any other braking issues.
Below are the steps to follow when replacing the brake pads.
- Step 1. Continue from (step 2) above
- Step 2. Secure the brake caliper on the vehicle
- Step 3. Slide the worn brake pads off
- Step 4. Apply brake lubricant to the new brake pads and slide them on
- Step 5. Reinstall the brake calipers
- Step 6. Reinstall the wheel
- Step 7. Repeat the process on other wheels
Here is a video showing the steps to replace brake pads.
Replacing all the brake pads will cost you between $200. If done in a repair shop, this can be $650.
Warped brake rotors are another reason your car may make grinding noises when braking. Brake pads grind on rotors in a braking instance.
As mentioned earlier, braking involves generating lots of heat, which, if in excess, can cause the brake rotors to warp. Hard braking or worn brake pads are some of the reasons the rotors overheat and warp.
Access and observe the brake rotors to confirm that they are behind the grinding noises when the car brakes. Observing the rotors involves removing the wheels and checking for hotspots and grooves.
You may also experience other symptoms like the brake pedal pulsating or the steering wheel shaking when braking.
The following video shows how a warped brake rotor looks like
Warped rotors need replacing, which you can do by following the steps below;
- Step 1. Gather the necessary tools, including a wrench (some calipers need an Allen hex wrench), jack, and jack stands.
- Step 2. Remove the wheel.
- Step 3. Unscrew the brake caliper and remove it.
- Step 4. Pull out the brake rotors.
- Step 5. Put in the new brake rotors.
- Step 6. Reinstall the brake calipers.
- Step 7. Install the wheel.
- Step 8. Repeat on the other wheels.
Replacing the brake rotors can cost you between $130 and $250 per wheel, depending on the part and labor cost.
The following video shows how to replace the brake rotors on a car.
Lack of lubrication is another possible reason your car grinds when braking. Since the brake system has many moving parts, they must be lubricated all the time to have optimal performance.
Brake pads, rotors, and calipers are some of the parts that require lubricating and can make grinding noises if unlubricated. You should lubricate them at least once monthly.
Lubricate all the braking components, starting with those that are dry and looking rusted, using a lubricating grease of your choice. Start with the brake pads, calipers, and rotors, lubricating all the sliding and moving components.
Wipe and lubricate caliper bushings, abutment clips, and slide pins. Brake pads need lubricating at the edges. This solution is cheap since most lubricants are under $30. However, if done by a professional, it will cost you more than $100
The below video shows how to lubricate the calipers and pads.
Another possible reason the car makes grinding noises as it brakes is because of a loose component in the braking system. Usually, various parts of the braking caliper may be loose, like brackets and anti-rattle pins, causing grinding noises when you brake.
Access the brake caliper to check for a loose part that is causing the grinding noises. The brake caliper itself can be loose. Loose brackets and anti-rattle clips can cause grinding noises.
To access the calipers, follow the steps below;
- Step 1. Remove the wheel.
- Step 2. Wiggle the caliper to confirm if it’s mounted tightly on the mounting bracket.
- Step 3. Unscrew the calipers and check whether the anti-rattle clips are on.
The solution to a loose braking component is to tighten it. If the calipers are loose, screw the caliper and torque to the required specs. Usually, it’s between 47-62 ft. lbs. But consult the user manual for the correct specs.
Reinstall the anti-rattle clips to ensure they don’t move when the vehicle runs.
Debris between the brake pads and calipers can also cause grinding noises when the vehicle brakes. Small rocks are the common debris that can cause this issue with the braking system. Small rocks and other debris are common in vehicles regularly driven off-road.
Since debris is visible, access the brake pads and rotors to see whether there is any in-between. Follow the steps below to get to these parts.
- Step 1. Remove the wheel.
- Step 2. Unscrew the brake pad caliper.
- Step 3. Remove it and observe between the brake pads for debris.
- Step 4. Also, if your vehicle has drilled rotors with holes, check the holes for stuck stones that may be grinding on the brake pads.
If your brake pads or rotors have stuck debris on them, unstuck them and remove them. The solution is straightforward and will involve only tapping gently on the stuck item to loosen it.
Afterward, wipe these parts and reinstall them back on the vehicle. Remember to tighten them. This issue’s diagnosis and solution can cost you between $35 and $80 if done by a professional.
Following are some related questions about grinding noises when the car brakes.
Q1. Can I Drive a Car With Grinding Brakes?
It’s ill-advised to drive your car when there are grinding noises when braking. The noises mean something is wrong with the system, and the braking performance is low. Get the noise diagnosed and fixed soon before driving the car.
Q2. Do Brake Pads Generally Make Noise When Braking?
Brake pads don’t usually make noise in a braking instance where they grind on the rotors. However, low-quality brake pads are made with more metal than friction surfaces and are more prone to noise. If your new brake pads make grinding noises, replace them with quality ones.
Q3. Can Rusted Brake Rotors Cause Grinding Noises When Braking?
Rusted brake rotors can cause grinding noises as the vehicle brakes. A car used occasionally is likely to get rust and make grinding noises when braking.
The grinding noises in your vehicle when braking have various possible causes that must be determined and fixed. The possible causes include worn-out brake pads or warped brake rotors. However, lack of lubrication or debris in the braking system can also be the cause.
Diagnose each problem to determine whether it’s behind the grinding noises. Follow the steps in the article to fix the issue once you’re certain it’s the cause. However, if you’re uncomfortable handling the repairs, you can hire a professional to help you.