What's Wrong With the Brakes on My Car?

What's Wrong With the Brakes on My Car?
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Keeping your brakes serviced and in good condition will help prevent brake failure and serious safety issues, but you need to know what symptoms to look for in order to diagnose and fix the problems with your vehicle's braking system.
Squealing Noises
Squealing brakes are a common problem. Most modern vehicles have replacement indicators that emit a squealing noise to let you know it is almost time to change your brake pads. It is usually not cause for alarm, as the vehicle will not be dangerous to drive immediately, but you will need to replace the pads in the very near future.

Another frequent cause of squealing is moisture buildup around the brake pads. If the squealing occurs only in the morning or after a rain shower, it is probably nothing to worry about. If the noise does not go away after several minutes of usage, have your brakes checked by a professional.

Brake Vibration
Vibrating or pulsating brakes are usually signs of warped rotors. If your rotors are warped, depressing the brake pedal will cause an uneven rotation around your rotors. Warped rotors can sometimes be resurfaced and fixed, but they will usually require replacement. They can decrease the effectiveness of your braking system, so get this problem checked as soon as possible.

The best way to prevent warped rotors is to avoid slamming on the brakes whenever possible and to have your rotors turned every 20,000 miles.

Scraping Noises
If you hear a scraping noise (metal to metal) when using your brakes, it is a sign that your brake pads are almost nonexistent. The noise you are hearing is the caliper making contact with the brake disc. Bring your car in for service immediately, as worn-out brake pads will greatly decrease the effectiveness of your brakes.
Resources
reference
Common Brake Problems
resource
Consumer Auto Repair Resource

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