Automobile brakes function like an energy converter. It converts frictional energy to heat through a mechanical system. for a brake to withstand its forces, It has to be of the right thickness and quality.
Hearing strange sounds from cars can be disturbing, and grinding noise when braking can be frightening! Grinding brakes usually sound like a hard metal to metal sound. Sometimes brakes grinding when not applied may send a more serious message.
If you hear this sound, it means your brake pads have worn out to the extent that their metal linings are exposed, and these metal linings are now rubbing against the metal of the brake pads.
This doesn’t just expose you to the risk of brake failure on the road, but it may also damage the rest of the braking system, including the rotor and calipers. Although replacing the brake pads is easy, if you don’t do this, it may cause more complicated problems!
Understanding Brake Grinding
Brake grinding is a sound that most drivers will be familiar with at some point. It’s an unsettling, high-pitched noise that usually occurs when the brake pads come into contact with the brake rotors in a way that isn’t typical.
While this noise can be annoying, it’s also a warning sign that something is wrong within the brake system.
The purpose of your car’s braking system is to safely stop the vehicle. The system relies on several components, including the brake pads and rotors, to generate enough friction to bring the vehicle to a halt.
When these components are compromised or worn out, they can create friction that produces a grinding noise.
This noise should never be ignored, as it can signal underlying problems that may affect your safety on the road.
Symptoms of Brake Grinding
If your car is making a grinding noise when braking, you might experience additional symptoms that point to a specific issue within the braking system. Recognizing these signs early can help prevent further damage.
#1. Grinding Noise During Braking.
This is the most obvious symptom and often indicates worn brake pads or damaged rotors. The noise is typically louder when braking at low speeds or coming to a complete stop.
#2. Reduced Braking Efficiency.
If you notice that your braking distance has increased or the brakes don’t respond as quickly, it could be due to glazed or worn-out brake pads.
#3. Vibration in the Brake Pedal.
Vibrations in the brake pedal can accompany the grinding noise, especially if the rotors are warped or damaged. If you feel this sensation, it’s essential to have the braking system inspected.
What causes grinding noise when braking?
#1. Worn Brake Pads.
By far the most common reason you’ll hear grinding from your brakes is worn brake pads. These components have a friction material that gradually wears down with use.
Most pads also have small metal tabs called wear indicators that start squealing before the pad material is completely gone (this is your warning to replace them soon).
If you ignore that squealing sound, the friction material will wear away completely, leaving only the metal backing plate. When this metal plate contacts your rotor, it creates that unmistakable grinding noise.
At this point, you’re not just damaging the remaining pad material, you’re also scoring and damaging your rotors, which turns a relatively inexpensive brake pad replacement into a more expensive brake rotor replacement.
#2. Rusty or Uneven Rotors (aka: “Warped” Rotors).
What many people call “warped rotors” are almost always rotors with uneven thickness or pad material deposits, not rotors that have physically bent out of shape.
True warping is extremely rare. Instead, heat buildup and uneven brake pad contact can leave high and low spots on the rotor surface, which creates vibration, pulsing in the brake pedal, and sometimes scraping or grinding noises.
Surface rust is another common issue, especially if your car sits for extended periods or you live in a humid climate. Light rust usually wears off after applying your brakes a few times, but heavy rust can create pitting or an uneven surface that causes grinding.
#3. Debris Stuck Near Rotor.
Sometimes the grinding noise isn’t from worn components but from foreign objects that have found their way into your brake system.
Small rocks (very common), rust flakes, or other debris can get lodged between the brake pad and rotor, or between the rotor and the dust shield behind it.
This type of grinding often starts suddenly and may be intermittent at first. In case of a rock or piece of gravel, the grinding noise will probably be loud.
The good news is that debris-related grinding is usually easy to fix. Sometimes you can dislodge the debris by driving forward and backward while gently applying the brakes.
If you have access to an air compressor, you can try using an air blow gun to clear debris using compressed air without removing the wheel.
However, if the grinding persists, the debris may be severely lodged in there and have already caused damage. You’ll likely have to remove the wheel (and possibly brake components) to get to it or get professional help.
#4. Faulty Brake Caliper.
A brake caliper that’s stuck or not functioning properly can cause grinding noises in several ways.
If a caliper seizes up, it may not release the brake pad completely from the rotor, creating constant contact and grinding even when you’re not braking. This often produces a grinding or dragging sound while driving.
A stuck caliper can also cause uneven brake pad wear, leading to metal-on-metal contact on one side while the other side still has pad material left. This is similar to what the most common cause is. It’s just a much faster way of getting there.
Additionally, worn caliper hardware like slide pins can cause the caliper to sit at an angle, creating improper contact between the pad and rotor. This is a more serious issue that affects braking performance and requires immediate attention.
#5. Brake Hardware Issues.
The brake system includes various small but important hardware components that keep everything aligned and functioning smoothly. These include clips, springs, shims, and anti-rattle devices that hold the brake pads in the correct position within the caliper.
When any of this hardware becomes worn, corroded, or is not reinstalled during a brake job, brake pads can shift or vibrate against the rotor in ways they shouldn’t. This can create grinding, rattling, or scraping noises.
Sometimes you’ll only hear these sounds during light braking or when driving over bumps. While brake hardware is relatively inexpensive, the labor to replace it is often similar to replacing the brake pads, so these components are typically replaced together during brake service.
#6. Damaged or Bent Dust Shield.
Behind each brake rotor is a thin metal dust shield designed to keep debris away from the brake components. These shields can become bent or damaged from an accident, road debris, improper installation, or corrosion, causing them to contact the rotor as it spins.
A bent dust shield typically creates a constant scraping or grinding noise that happens while driving, not just when braking. The sound may change pitch as you speed up or slow down, and it might be more noticeable when turning.
This is usually a minor issue that can be fixed by carefully bending the shield back into position or trimming away the damaged section.
However, it’s important to make sure the noise is actually coming from the dust shield and not from more serious brake component problems.
Other Causes
- Low Quality or Glazed Brake Pads: Cheap brake pads (here’s looking at you Temu!) or pads that have overheated can develop a hard, glazed surface that creates grinding noises. These pads may also contain metallic particles that scrape against the rotor.
- Bad Wheel Bearings: Worn wheel bearings can create grinding or rumbling noises that may be mistaken for brake problems. This noise typically gets worse with speed and may change when turning.
- ABS Issues: A malfunctioning ABS system can cause grinding or buzzing noises during braking, especially during emergency stops. This is usually accompanied by warning lights on the dashboard.
Brakes Grinding Situations
There are main situations that could cause brake grinding:
#1. Brake Grinding When You Press On Your Brakes.
If you notice your brakes are grinding while slowing down, it’s probably due to a lack of thickness in your brake pads. Your brake pads must be thick enough to provide adequate performance and halting power.
Over time as you use your brake pads, they will eventually wear out. When your brake pads are thinner than the suggested thickness, they will begin to screech every time you press the brake pedal.
This uncomfortable sound is known as brake scrubbing, indicating that it is time to upgrade the brake pads. If you ignore this noise, the brake pads will continue to wear out, and the squealing sound will become a grinding noise.
If your brakes make a sharp grinding noise while decelerating, the brake disc and caliper are likely scratching together. The sound often appears when your vehicle comes to a complete stop, but you may also hear it as you step on the brake pedal.
The best way to resolve this problem is to have your brake pads replaced as soon as possible, but you may also need to replace both your discs or rotors at this point.
#2. Brake Grinding While Driving.
If you hear your brakes grinding when traveling at a steady speed, that may be due to rocks or pebbles lodged between the caliper and the rotor. In this case, you’ll want the debris removed from the system as soon as possible.
Lack of immediate action can severely damage the brake pedal and other performance components. While you can remove rocks and debris from your brakes, hiring a professional is always best, especially if you’re new to working on cars.
If you hear any brake grinding noises, you should schedule a service appointment with a car mechanic and have them inspect your vehicle.
#3. Brake Grinding When Your Vehicle Comes To a Sudden Stop.
Another common reason for a grinding noise from your brakes is when you suddenly slam the brakes. When you hit the brakes suddenly, you might hear a grinding noise and feel the brake pedal rattle.
However, if your brake pads are sufficiently thick, you should not need to replace your brake pads. If you hear grinding when you suddenly stop, it’s most likely caused by your Anti-Lock Braking System (ABS).
In a panic stop, the ABS will start automatically to stop wheel lockups and vehicle skidding. The system operates by pumping the brakes to maintain stability and control, resulting in the grinding noise and rumbling brake pedal.
#4. Grinding noise when braking but the pads are fine.
While most noises indicate that it’s time to change your brake pads – what will you do if you hear grinding noise when braking but your pads are fine? Also, you may notice new brakes making grinding noise at low speed.
Do not panic. New brakes make grinding noise until the brake pads perfectly fit the rotor surface. The following are reasons why your brakes might grind even when your pad is fine.
- Inferior Brake Pads: Cheap pads wear faster and offer less braking force than higher-quality pads.
- Faulty Shims: brake pads have shims behind them. On every pad replacement, the shim should also be replaced. The shim is the component that the piston pushes against the pad. Therefore if the shim is old and rusty, it will undoubtedly emit sounds.
- Loose or Rusted Caliper Bolts
- Rusted Pads or Rotors
- Brakes and Rotors Mated Improperly
- Faulty Wheel Bearings
- Debris Stuck in Brakes
- Faulty Self-Adjusting Mechanism
#5. Grinding noise when turning and braking.
If you drive and your car starts making grinding sounds while turning, you should suspect three causes; inferior wheel bearings, bad CV joints, or a brake assembly problem.
The Bearing act like a buffer between the axle and the wheel. Therefore, they prevent friction between two moving parts. As a result, worn wheel bearings generate friction, which produces grinding noise when the car is turning.
A little-known fact is that problems with constant velocity joints can cause grinding noise during rotation. Constant velocity joints are components of the driveshaft and play a key role in steering.
Another critical source of strange noise may be problems with brake components. The key issue is that the brake cover is loose, the brake caliper and brake pads are worn out, or the rotor is not aligned. In any case, the best way is to check the entire braking system.
#6. Brakes grinding at low speed.
If you hear brakes grinding when braking and your car is at a low speed, this might indicate something serious or not at all.
For safety, it is advisable to stop the vehicle and check the cause of the noise. The following are things to watch out for because they are most likely the cause of brake grinding at low speed.
Worn out braking pad: graphite, copper, and iron are materials used to manufacture brake pad. as you use the brake pad, this material keeps wearing out until the outer metal cover touches the rotor.
Low-quality pad: If you just had a pad replacement and every reason for pads being worn out is ruled out. Then you might check if you bought the wrong pad.
Worn out rotor disc: the consequence of not changing worn out or fake pad is worn out rotor disc. Your rotor disc is worn out because you might have exposed it to cold water while still hot. Such an act can lead to a surface deflection of the rotor, leading to grinding sounds when braking.
Other reasons include:
- Solid item stuck up in between the pad and the rotor.
- Parking the car for too long
- Unlubricated caliper screws
- Broken shims
How to Identify Which Wheel is Making the Noise?
Figuring out which wheel is making the grinding noise can help you determine the severity of the problem, fix it yourself, or communicate it more effectively with a mechanic. Here are several methods you can use to pinpoint the source.
#1. Listen While Driving.
Roll down your windows and pay attention to whether the grinding seems to come from the front or rear of the vehicle, and from the left or right side. Front brake problems are more common since front brakes do most of the work, but don’t assume… listen carefully.
#2. Test at Low Speeds.
Drive slowly in a safe area like an empty parking lot and apply the brakes gently. Sometimes you can hear more clearly which side the noise is coming from when you’re not dealing with road noise and wind.
#3. Check for Visual Clues.
Look at your wheels for signs of brake dust or metal shavings around the rim. Excessive brake dust on one wheel compared to the others often indicates a problem on that side.
You might also notice discoloration on the wheel from heat if there’s a stuck caliper or severe grinding.
#4. Feel for Pulling.
If your car pulls to one side when braking, the problem is likely on the opposite side. A car that pulls left during braking often has an issue with the right brake that’s preventing it from working as hard as the left side.
#5. Professional Diagnosis.
If you can’t determine which wheel is causing the noise, any mechanic can quickly identify the source during an inspection. They can also determine if multiple wheels have problems, which isn’t uncommon.
How do you fix grinding brakes?
Several reasons cause grinding brakes, and the most common is worn out or faulty brake pads. Below are procedures for installing a new brake pad; the first step is to keep the required material and tools close by.
The materials include
- Mechanic gloves
- Jack and Jack stand
- C-clamp or a retract wood.
- A new brake pads
- Brake fluids
- Lug wrench
- Adjustable wrench
- Turkey baster
- Plastic tie
Step 1: Wheel Removal.
In other to remove the wheel, lose the nuts on the wheel. Then jack up the car and place the jack under the frame of the car.
Lower the jack so that its weight rests on the jack support. Completely remove the lug nuts and remove the wheel. Now you can use the brake assembly and can safely reach under the car.
Step 2: Remove the slider bolt.
Locate the pins, also known as slider bolts, that clutch the caliper in position.
Step 3: Pivot the caliper up.
Remove the caliper bottom bolt, and swing the caliper upward. At this time, it is very easy to check the thickness of the brake pad to confirm whether it needs to be replaced.
Wear indicators are often present in most brake pads, these small metals function by giving off a squeaking sound when it contacts the rotor.
Even if they have not touched it yet, if the thickness of the friction material is 1/8 inch or less, the pad needs replacement.
Step 4: Slide out the old brake pads.
At this point, you can visibly see the brake pads and the retaining clip holding it loosely. Remove the old pad by sliding it upward and gently.
Step 5: Replace the retaining clips.
Most new pads come with clips, allowing the pads to slide back and forth easily. Use the new one and discard the old one. The clip does not have a retaining screw. They just snap into place.
There are usually left-handed and right-handed clips, so please change them one at a time to make sure they match exactly when you use them.
Step 6: Slide in the new brake pads.
The new pad will slip into place as easily as the old ones when removed. Although sometimes the new clip will be tighter.
Step 7: Retract the pistons.
The Pistons’ job is to press on the brake pads and squeeze the rotor to stop the car. Your car may only have one or two pistons per wheel, but the principle is the same.
Before lowering the calipers into place, these pistons need to be retracted (pushed back) in order to remove the new thicker brake pads. This section requires steady pressure and patience.
Step 8: Monitor the brake fluid level when.
The piston is pushed back, the brake fluid level rises slowly. Open the main tank reservoir and check frequently. This is a bigger problem when you are working on the second brake because the total fluid volume of the two calipers may cause the brake fluid to overflow.
There have been cases of overflowing due to topped-up fluid during servicing. (this is the reason you don’t just top-up).
The fluid level will naturally drop as the brake pads wear. And it will increase after the pad replacement, provided the level doesn’t drop below the MIN mark.
Step 9: Reposition the caliper.
If the piston has been retracted, it becomes very easy to slide in the caliper. Sometimes it doesn’t fit correctly and the caliper will slip over the new pad. Also, if the piston gets trapped on the pad, then you should check if the piston was completely retracted.
Step 10: Reinstall the slider bolt.
Fix back and torque down the sliding bolts. Straighten the wheels of the car, and mount the tires. Lastly, ensure you torque down the log nut to the manufacturer’s spec.
Step 11: Carry out these steps on all sides of the wheel.
Repeat the above steps for the other side of the front brake. Remember that since you have installed a new brake on one wheel, the amount of brake fluid in the tank will be higher.
Step 12: Test and run the car.
Test run the car within short distances to ensure the noise is cleared off. Note that the engagement point of the brake pedal may be higher. You will adapt to this within a short time.
As I mentioned earlier, there are several factors that can cause a grinding noise. If the cost of the grinding noise is not from the brake pads, it can be a result of a defective shim, Unlubricated caliper bolts, or bad wheel bearings.
If it happens to be a result of stiff caliper bolts, you can lubricate and fix them right back. If the grinding noise is caused by defective shims, get a new one and replace it.
If it happens to be a defective wheel bearing, you’ll have to seek professional advice or our previous post on the Symptoms of a bad wheel bearing and fixes.
How much does it cost to fix grinding brakes?
The price of fixing your grinding brake depends on the brand and model of your car. If the issue isn’t that severe, the only thing you need is pad replacement, which has an average cost of $250.00.
A large part of this cost is being paid for labor. Another thing you may be asked to replace is the rotor.
Brake pads attached themselves to the rotor in the form of a clamp to stop the wheel from spinning. Replacing a rotor is more expensive than fixing a new brake pad. It cost about $406 to $559.
FAQs.
Q: Are grinding brakes dangerous?
You must have heard the word safety. Any act that can’t be performed safely shouldn’t be performed at all—driving a vehicle with a grinding brake isn’t safe. Immediately you notice the sound, stop driving and contact your mechanic.
Further driving can cause more damage to the brake disc or drum. Another risk involved is total brake failure. If a mechanical fault causes a grinding brake, continuous driving may cause the brake force to be ineffective, thereby leading to an accident.
Q: How long can you drive with grinding brakes?
It depends on the severity and the intervals between grinding if you notice a grinding sound from your brake pack immediately and check it out.
Although it is possible to drive it for a while, this is not advisable because it can make the situation worse and increase the repair cost. Furthermore, driving a grinding brake can affect the entire brake system.
Q: Can grinding brakes catch fire?
A variety of reasons can cause grinding. However, if it involves metals rubbing against each other, causing it to produce heat and sparks, it can catch fire, especially if there is flammable fluid in the car.
However, the leading cause of brake catching fire is improper repairs and careless driving. The following reasons can make a break catch fire: brakes losing their functions, brake fluid boiling in the calipers, and excessive heat in the automobile.
Q: Will the brake fluid stop grinding?
No brake pad won’t stop brake grinding. Brake fluid has nothing in connection to brake grinding. It is a hydraulic fluid for the brake system.
Even if the fluid is filthy, it won’t cause the brake to grind. Grinding causes have been mentioned earlier, so don’t let a mechanic talk you into changing your brake fluid because of grinding noise.
Final words
A grinding break is a course for concern. The brake is an essential component in automobiles and, as such, deserves care.
Although there are times when the grinding noise when braking isn’t caused by something serious, every time you hear the sound, you must check for the cause and take the necessary action.
A common cause is the worn-out brake pad. This can be easily replaced and doesn’t cause as much as changing the roto or shim. A simple maintenance routine like lubrication, servicing, and prompt actions can save you more.