Brakes are simultaneously one of the easier pieces of maintenance for relatively new home mechanics to tackle and one of the most important things in your car that you don’t want to mess up. Brakes that work right are the difference between life and death, between stopping and ending up in a ditch. So when you hear a weird noise or feel something off in your steering wheel whenever you brake, you don’t want to waste time before you do some car troubleshooting and find out what is wrong with your brakes.
So, lets say that you jack your car up, take those tires off, and see that 3 out of 4 of the brake pads on your disk brakes look perfectly fine, but that 4th one looks much thinner than the rest. It looks as if it’s been in use way longer than the other 3, despite the fact that they were all put on at the same time. Or, the wear on an individual pad might be off, with one side of the pad thinner than another. As you have probably guessed, this isn’t the way things are supposed to work. One part of the same pad shouldn’t be wearing more quickly than another part. And though brake pads don’t wear perfectly evenly all around, the difference should be within millimeters of each other. Anything bigger than that, you have some car troubleshooting to do.
Possible Culprit 1: Your Brake Rotor
Depending on what sort of car you have, your rotors may be reused over the life of several brake pads, or with more high performance import cars, they may need to be replaced with every brake pad change. Regardless, as the rotors get older, they get thinner. Because of this they are more likely to warp when they get too hot when braking a lot while going downhill or being suddenly cooled after being hot from use. If your rotor is warped, your brakes are going to wear unevenly because the rotor and brake pads aren’t coming together perfectly.
If you feel shuddering or shaking in your brake pedal when you hit the brakes, especially on a hill, your rotors might be at fault. If that shuddering translates to your steering wheel, it is probably your front rotors. Depending on how bad the shuddering is, the surface of the rotors may even be visibly wavy. If the rotors aren’t flat, this may be contributing to your uneven brake wear issue. Regardless, you should get any warped rotors changed ASAP, whether you DIY or get your local auto repair shop to take care of it.
Possible Culprit 2: Your Disk Brake Calipers
Whenever you took your brake pads off, you undoubtedly took note of which location held that pad that was thinner than the rest. This brake caliper is where you should begin your search. One of the most common causes of uneven brake wear has everything to do with the brake caliper. When you hit your brakes, a piston behind the brake pad extends, clamping the two brake pads against the disk in between them. When you release the brakes, the piston should immediately retract, allowing both of the pads to move away from the disk once again. If it doesn’t retract properly, however, you are going to get uneven wear. Check out the rubber boot that is around the piston. If there is any sign of brake fluid or the boot is torn, there is a huge possibility that your caliper is faulty and needs to be replaced. If you have a harder time pressing that caliper in than others when you change the brake pads, its definitely time to take a closer look.
Possible Culprit 3: Floating Caliper Slide Pins
If you have a fixed brake caliper, you can go ahead and check this off of your list right away. No caliper slide pins? Then this isn’t why your brake pads are wearing unevenly.
If you do have a floating caliper, however, it’s time to take a good look at those caliper slide pins. These pins, which you had to take off to get the brake pads out, allow both brake pads to be applied through the use of pistons on only one side. These pins allow the rotor assembly to move enough that the outer pad is pressed as well as the inner pad, though the piston is only on the inner pad. But if these bolts don’t move freely, neither can the assembly. So take a look at the pins. Make sure they move comfortably as they are supposed to without getting hung up on any corrosion. Check their rubber boot on the slide pins as well. If they are getting hung up, you will want to pull out the pins and check them. You might be able to get away with a wire brush and some elbow grease to get them functioning properly again, or you may need to invest in some new pins.
Possible Culprit 4: The Brake Pads Themselves
During the installation process, the brake clips and brake pads have to be fitted into place on the mounting bracket. Because they are designed to be snug, it can be possible to for the pads to be installed crookedly, so one side of the pad is being pressed against the rotor before the other side when braking. Since the caliper and the mounting bracket are usually exposed to a great deal of dust and salt, it can be difficult to put the brake pads perfectly in place if there is extra corrosion or gunk on that bracket. If a single pad is worn more on one side than the other, this is probably your culprit. Make sure your brake pads are perfectly parallel to the rotor during installation.
Don’t Skimp on Your Brakes: An Auto Repair Shop Can Help
Though we like to think all auto solutions are fairly straightforward, sometimes car troubleshooting gets more complicated. If you have torn your brakes apart and are still scratching your head trying to find a solution, it’s time to take it to your local car repair shop. Though Google can help with some problems, any professional car mechanic has way more practical information between their ears and the know-how to see it through. Though it can be tempting to just figure it out yourself, save yourself the headache and have your favorite auto repair shop take a look.
