You know how to check your car's other vital systems--oil, tire air, and gas--but what about the brakes?
The trouble with brakes is that they can fail anytime. Depending on the type of driving conditions they have been exposed to, their wear rates can drastically differ, too.
But if you look for the obvious signs, you'll know when to get them serviced before they turn into a problem:
Keep your driving habits in mind. If the majority of your driving is done over the interstate during long trips that require little braking, miles are not a good barometer for keeping tabs on your brake wear. A more accurate measure might require some introspection into your driving style, do you anticipate the stop ahead by reducing speed prior to braking or do you “ride the brake” in preparation for a stop?" If so, you're going to go through brake pads more often than other drivers.
Check at a regular interval--as insurance. If you had to pick an interval at which to start checking your brakes it probably would be 15,000 miles. This discounts the possibility that a problem has developed due to external problems like road debris lodging between the pads and the rotors, or the failure of hardware or brake calipers, which can rapidly wear out brake pad material.
Get a feel for the pedal. Braking distances and brake pedal feel taken together are keys to knowing that your brakes need to be checked. If the pedal feels soft or seems to travel too far to the floor and it takes longer for the car to stop, you should have your brakes checked by a professional. On the other hand, if the pedal is high and hard and you hear a hissing sound your problem could be due to a vacuum leak or a problem with the brake booster and merits a look from a pro.
Listen for squeal and chatter. If you hear your car braking, chances are it needs your attention. I like to call it a “scrunch,” but many drivers describe it as a metal-on-metal sound. It may not happen each and every time you brake, but if you hear it, you can bet that it is not going away. The brake pad material has worn out and what you are hearing is the steel frame to which the pad material was attached contacting the disc brake rotor. You are now scoring the brake rotor and depending on how deeply the rotors are gouged, you may need to replace them. At the very least they will have to be resurfaced as part of the relining process.
Check for a pulse. Other conditions that should be referred to your mechanic are fading and pulsing. Fading is when your initial application of the brake pedal seems to take hold, but then there is a surge accompanied by the sensation that the brakes are not holding. Pulsing is when there is intermittent backpressure on your foot as you apply the brakes. This may be caused by some distortion of the brake rotor, possibly the result of applying the brakes when encountering a pothole and warping the rotor.
Finally, there are catastrophic failures caused by a sudden loss of brake fluid. This is not anything you will forget quickly and you will not have to be coaxed to seek professional help, if it happens. Unfortunately, it is occurring more frequently as transportation departments increasingly use corrosive chemicals to treat roads in the winter and car manufacturers look for anti-rust treatments to replace preparations that were found to be harmful to the environment or to personnel involved in the application process.You will always need to have your brakes checked. Knowing when and why can be helpful and in the end save you money as well.