When you step on the brake pedal of a vehicle with a disc braking system, all the brake pads are supposed to rub against their corresponding brake disc rotors at the same time. The brake pads have friction material which slowly gets worn down as the friction occurs. In a normal situation, the friction will wear the material evenly on each brake pad. But if the friction material wears down unevenly amongst the different brake pads, then it may seem confusing as to why this is happening.
Your first instinct may be to just replace all your brake pads. This is not a good idea because some of your brake pads probably have more friction material than others. Why would you want to throw them out if they’re still usable? The only reason you would is to have new brake pads which have the same amount of friction material as the other brake pads you’ve installed.
However, what is going to stop the same thing from happening again? After all, it wasn’t the fault of the brake pads for wearing unevenly. Something else in the braking system must have caused that to happen. You need to figure out what the cause is, or else your new brake pads will suffer the same fate.
Top 5 Causes
Below are the top 5 causes of brake pads wearing unevenly. Consider each cause as a possible reason for why your brake pads are wearing unevenly. The only way you can verify the cause is by having the braking system inspected by a professional mechanic. Of course, if you’re experienced at repairing automobiles, then perhaps you can perform the inspection and make a diagnosis yourself.
1) Uneven Rotor Thickness
Not only do your brake pads need to have the same level of thickness, but your brake disc rotors must also have the same thickness level as well. If you have uneven rotors, then it will cause the friction material of your brake pads to unevenly wear down as they rub against them. Check the rotors are flat spots and other differences like that.
2) Misaligned Brake Pads
When brake pads are installed, they’re supposed to be aligned evenly. But if you get a mechanic who doesn’t care so much about these minor details, then they may install your brake pads unevenly. If this happens, your brake pads will be misaligned each time you apply the brakes. Misaligned brake pads will wear unevenly rather quickly. If you’ve recently had new brakes installed and you notice this problem, then it is probably the mechanic’s fault for installing the brake pads unevenly.
3) Sticky Brake Calipers
As time goes on, dust particles and other debris will build on your pistons. Rust may also form on your pistons as well. When these things happen, you can expect your brake calipers to get sticky. Once you have sticky calipers, the pistons cannot slide properly. You need pistons to slide properly or else the brake pads won’t rub evenly against the rotating brake disc rotors. As a result, the brake pads will wear down unevenly.
4) Different Brake Pads
All your brake pads should be the same type. Do not mix brake pads in your braking system because they’ll certainly wear down unevenly. Each type of brake pad has a different amount of friction material, so you can’t assume they will wear down evenly.
5) Dirty Discs
It is easy for dirt, grease, and other debris to get onto your spinning disc rotors. That is why it is important to clean your brake discs periodically. If you don’t, then the dirty discs may cause your brake pads to wear unevenly. Use a brake cleaner product which is formulated to remove debris from discs. This will also reduce the chances of rust forming on them too.