Sooner or later, it's going to happen, and it's not a matter of if so much as when. Fortunate are the very few who never, ever hear them. However, for the vast majority of motorists, it's going to be as sure as death, taxes, and traffic around a mall sale on a payday weekend. I'm talking about squeaky brakes and like the aforementioned, everyone will encounter them sooner or later.
Unlike death, taxes, or traffic, there is something that can be done about squeaky brakes. No motorist should ever have to put up with them for long, if at all.
First off, let's get this out of the way now. There is a simple way to rid the world of squeaky brakes and banish them forever. It's called regular preventive maintenance service. A periodic inspection of the brake surfaces and components will almost always prevent squeakiness from ever happening. There are exceptions, of course, but those require driving in conditions where a lot of debris and foreign objects are stirred up by the tires.
Which leads us to why squeaky brakes exist. More often than not, as the brake pads or brake shoes wear down, the metal surfaces that make up the brake rotor or drum develop grooves that run along their surface. It's in these grooves that the occasional errant metal shaving and/or persistent micro pebble get stuck. What happens next, we already know. Brakes make that high-pitched squealing sound, as the friction material that the brake pad or brake lining is made up of drags on top of the foreign invader--or drags it along to dig deeper into either surfaces of the brake pad or braking surface.
Ridding the offenders is easy enough. It's just a matter of cleaning the brake surfaces. Handy with tools? Then you'll likely already know the next part. Put on your safety glasses, dust mask and work gloves and let's get cracking:
1) Loosen the wheel nuts of the noisy corner.
2) Raise the affected corner up, making sure to chock the wheels before you do.
3) Remove the wheel to gain access to the brakes.
4) Unbolt the calipers and move them out of the way safely. Skip to the next step if you're working on drum brakes.
5) Remove the rotors or drums.
6) Locate the problem area. Be ready with some elbow grease.
7) Sand down the affected area. Be sure to do both the rotor/drum and the pad/lining surface. It doesn't take much, but use your best judgment.
8) Put everything back together and go for a road test. Don't forget to start slow.
It goes without saying: If you've never done this, it's best left to a professional. If you plan to DIY it, you'll be doing so at your own risk. The simplified process described above is meant to be informational, not instructional. Videos online are helpful, as is a service manual and your car-savvy friend who does it on a regular basis.
Another cause for squeaky brakes is when the friction material of the brake pad wears down to a certain depth. Brake pads have minimum thickness warning devices built in--these are usually metal tabs that contact the brake disc to make the squealing sound. When you hear it, don't make friends with it. The longer you hear it sing, the more your rotors get damaged as the metal tab slowly digs in. This will make your pocket book lighter as you will need to replace your rotors, too. This applies only to disc brakes, as brake drums, to my recollection, don't have the warning devices built in. The fix is similar to cleaning them, except that parts are replaced as needed.
When minimum thickness is the cause of the squealing, there is still enough friction material to go further before metal to metal contact happens. You pay more for repairs, though. It's good to know that you can still drive if you absolutely have to, like in the case of emergencies. Still, it's best to avoid getting yourself into that situation.
Like the squeaky wheel that gets the oil, squeaky brakes should be attended to as soon as possible. Scrimping on them to save a few pesos isn't worth the potential accident waiting to happen. Be smart, read the manual, and regularly service your vehicle.
Everyone, including your passengers and road users around you, will be much better for it. Oh, and it's your brakes. Break is what happens to your car when you don't brake.