Have you been hearing grinding noise out of your car brakes? If yes, then it must be making you very anxious. It’s not only annoying to hear brakes grinding, but it can also damage your car further if you keep ignoring this warning sign.
Brakes are highly stressed component of a vehicle and it’s nothing to worry about if it makes some squeaking sound now and then. Ever heard a race car make a squeaking noise when brakes are applied gently? That’s perfectly normal for a race car because the high performance sintered brakes have a lot of metal in them. These brakes are meant to do one thing: To have a very strong bite on the rotor disk.
But regular passenger car brakes need to be noise free. Sometimes we might hear squeaky noise now and then which is normal.
This is especially noticed when a car is driven after a long time and brake rotors have some rust deposit on it. This rust will clear out soon after the first few brake applications and it’s nothing to worry about.
However, grinding noise while braking needs immediate attention. How to check it? Drive your car at regular speed and brake all the way to halt (please ensure to do it in a safe environment). If grinding continues even as you increase brake pressure, then you need to look further into it.
What causes Brake Grinding Noise?
The most likely suspect of brake grinding sound is worn out brake pads. That’s why it’s recommended to stop immediately and inspect the issue. If you can’t figure it out then drive slowly to the nearest auto mechanic. That said, the grinding sound can also come due to other reasons. Let’s discuss all possible probabilities:
1) Used up Brake pads
As I mentioned before, the grinding noise from the brakes often comes when the brake pads are completely worn out. A few millimeters thick braking material is fused on the metal backing plate.
When the braking material is completely shod, the backing plate is pushed against the rotor. As you can imagine the metal to metal contact is quite rough on rotors. You definitely don’t want bare metal scraping on the brake rotor.
If you keep driving like this, firstly you’ll lose most of the braking performance, you’ll damage the rotors, and you could also damage the brake calipers if you keep driving like this for long. Keep reading if your brake pads are fine and you’re still hearing a grinding noise.
2) Foreign object stuck in the Braking System
Brake rotors and calipers are exposed to dust and grim all the time. But that’s perfectly normal. However, sometimes a big pebble or some other foreign object could get stuck in the braking system and rub against the brake rotor. This problem can be easily fixed by taking something like a screwdriver or even a pressure washer to pry out the foreign object.
3) Damaged Brake Shims
Brake pad shims are made out of metal and help keep the brake pads in perfect position in the caliper. They also make the brakes noise free. These shims can sometimes break and start dragging against the rotor. And that’s when it’ll make the brakes noisy.
Most people keep using the same shims for years and never replace them with brake pads. However, one should inspect shims every time brake pads are replaced. If you notice some wear, replace it with new shims and don’t wait for it to break and start causing problems.
4) Worn out wheel bearings
When wheel bearing wears out, it will make a grinding sound even when brakes are not applied. However, the noise can increase when you apply brakes. That’s because while braking, the bearings have to handle extra force. For the same reason, you’ll also notice that grinding noise will also come while taking a turn.
Other kinds of Brake Noise and why it happens?
1) Squealing Noise due to using Racing brake Pads on public roads
Some driving enthusiasts want the best brake pad for their daily ride. This is highly commendable as good brakes only add to the safety. But don’t make the mistake of using track use only brake pads on public roads.
These brake pads have lot of metal in them. On a racetrack, the brakes operate very high temperatures and that’s when they perform well. Yes, they wear off rotors quicker but that’s the cost of excellent braking.
The problem arises when you use them on the streets. These pads will constantly make squeaking noise and won’t offer good braking performance because they never reach optimal temperature on the street driving.
2) Brake pad wear indicator rubbing on rotor
Most cars have brake pad wear indicator. On German cars, it’s an electronic system that flashes warning on the dashboard when the wear indicator contacts the rotor. In other cars, it’s just a piece of metal that rubs against the rotor and make a squeaking noise.
Don’t ignore this warning message because if you do then you’ll be hearing grinding noise soon when the brake pad material completely wears off.
3) Unlubricated Caliper Guide Pins
Everytime you press on the brake, the brake pads move ever so slightly back and forth over the caliper guide pins. Therefore it’s recommended to add a dab of brake grease on the guide pins. This reduces the friction so that brake pads glide smoothly over it.
Most mechanics skip this step and even then the brakes remain noise free. But adding a layer of high-temperature grease is a good preventative measure. Apart from that, the grease also reduces the wear on the pins.
4) Clunking or Thumping Brake Noise
This kind of noise is most likely due to a suspension issue rather than the braking problem. When you brake the car nosedives and then comes back up. This can cause things like bad strut or shocks to make a clunking sound. Even lose brackets that holds cables can be the culprit.
Hopefully, now you are able to figure the cause for your brake noise. If you have anything to add please comment down below.
Are Grinding Brakes Dangerous?
Yes, grinding sound coming from brakes is definitely a sign that you should drive slow and get them checked for brake pad wear. Sqeaking sound on the other hand, is normal for high performance brake pads.
Can you keep driving with worn brake pads?
Yes you can, but shouldn’t. Apart from being dangerous, it can also damage brake parts like rotors and callipers. $50 brake pad vs $500 brake parts. You choose.