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know when your brakes are failing

That screeching or grinding sound may not be coming from your car radio (unless you're into that kind of thing) – it could be a sign that your brakes are slowly but surely failing. We'll help you understand and detect faulty brakes so you can fix them before they stop working.

How brakes are supposed to work

Unless you're a bodybuilder, the amount of force you create when you tap your brakes is probably not enough to stop a toy truck, much less a 3,000-pound car going 50 mph.

Which begs a question: how exactly do brakes work?

The force you use (tap vs. slam) to hit the brake pedal starts a chain reaction. How hard you hit the pedal communicates how much your car, and each tire, needs to brake. Fluid is sent to the brakes, allowing the braking mechanism to determine how much force it should apply.

The brake's hydraulics take the original force you created (though your tap) and multiplies it with the necessary force (the mechanics vary between disc and drum brakes, but we won't get into all that here). Brake pads are forced onto the tire, creating the friction and heat that should ultimately stop or slow your car.

Without getting into the fundamentals of leverage and friction, this is the basic principle of how brakes should work.

Why brakes fail

When a car's brakes can no longer create sufficient friction, your brakes fail. There are a number of reasons for this: the brakes can overheat, grease or oil can leak onto them, or you could simply wear through your brake pads. We'll help you spot the warning signs.

Detecting the symptoms of brake failure

tip
  • Don't ignore your antilock brake system (ABS) light when it pops up on your dashboard. It could mean there's a wiring or electrical problem.
  • Listen to your brakes. Brakes that squeal or grind aren't just a nuisance. They're a serious problem, as that squeal might be your brake pads wearing thin (and the grinding could mean you've worn your way down to the rotors). If you hear a clicking sound, the spring mechanism holding your brake pad in place may have broken or come loose. And if you hear a pulsating sound, you might have a warped drum or rotor. So keep an ear out for any abnormal braking sounds.
  • If your wheel gets the shakes every time you hit the brakes, this could be another sign that you've got a warped drum or rotor (which might need to be repaired or replaced).
  • Be wary of excess drag while you accelerate. Rust may have built up on your emergency brakes, which leaves them "on" even when the lever's down.
  • You could feel your car pulling from one side or the other if you have frozen brakes, brakes that are out of alignment, or fluid leaking on the brake pads or shoes.
  • Check your stopping distance. After awhile, you get to know your car like an old friend. And if your car needs more space to stop than you're used to, you may need a brake adjustment, new brake linings, or a replacement power booster.
  • If your brake pedal seems soft or spongy, there may be excess air in the brakes. Your mechanic can release the air through "brake bleeding." Don't worry, it's painless.

Each symptom could signal a bigger problem. If you notice any of the problems listed above, get your car to the shop for a brake inspection.

Preventing brake failure

The best way to save your brakes is through regular maintenance. Your car's manual should tell you how often to have your brakes checked. And if you suspect a problem, bring your car to a mechanic at the first sign, squeak, or squeal.

Related links

How to handle brake failure
If you're driving on sketchy brakes, read this page to prepare for an unexpected braking emergency.

Antilock brake discounts (among others)
You could score Esurance discounts for plenty of things. See what discounts we offer here.