ALT-1 What you need to know before having your Brakes Replaced
If you are considering having your brakes replaced there are a few things you should know.Firstly an understanding of what type of brakes your vehicle is equipped with. Next you should have a basic understanding of how your brakes function,and lastly be aware of signs of wear and trouble.
Most vehicles use front disk brakes these days. They can be identified by a shiny metal disk known as the rotor which is visible through the openings in your wheel. With the wide assortment of custom wheels on the road today, you can see the front disk brakes prevalent on almost all passenger vehicles. Rear disk brakes are common on performance vehicles, but are also finding their way into lower level vehicles as well. They look very similar to the front disk brakes with the exception that the rotor is often smaller in size as compared to the front.
Drum brakes are found on the rear of many vehicles. They do not use a shiny metal rotor like the disk brake design, but have a large dinner plate sized drum that is often rust colored from exposure to the elements. Quite simple, if you have a shiny metal disk behind your wheel you have disk brakes. If not, you have drum brakes.
While different manufacturers use different disk brake designs, the principles of operation are similar. The disk, or rotor is mounted to the vehicle using the studs which hold on the wheel. Both sides of the rotor are shiny smooth steel(performance rotors may have holes and or slots which allow for cooler operation and shorter stopping distance). A brake pad resides on each side of the rotor, and is held in position by a cast metal frame called the caliper. The caliper contains a piston (or multiple pistons, on performance vehicles), which presses the brake pad against the rotor when the brake pedal is depressed. This action draws the caliper to pull the other brake pad against the other side of the rotor. Hence the rotor is squeezed between the pads causing the rotor to slow, and stop.
Drum brakes use a forward an rear brake shoe which ride inside the rear drum. The inside surface of the drum is shiny steel as the rotor. Two pistons push the brake shoes outward against the drum to slow the rotation of the wheel. The shoes are supported by a series of springs, and linkages within the drum.
Brakes will wear. It is not on common for the front brakes to wear out faster than the rear as they do most of the work. Expect to get 40-50,000 miles on a set of front brakes, and around 70-80,000 miles from a set of rear brakes. Wear will depend on brake pad material, and driving conditions. Most disk brakes have wear indicators, which are small brackets, that will actually scrape against the rotor when the pad has worn thin enough. This will make a high pitch squeak while cornering and braking.Drum brakes do not have this warning device, so they should be inspected at least twice a year. If the brake pads wear to thin, the rotor or drum can get physically damaged, and will need to be resurface, or replaced.
Here are some signs to watch for.If you hear squeaking, or squealing coming from your wheels when coming to a stop. your pads may be wearing out.
If you hear or feel a grinding noise from any wheel, the pad has worn too thin and the rotor or drum is running metal to metal against the brake pad mounting plate. Pads must be replaced, and rotor and or drums must be resurfaced or replaced.
If the vehicle pulls to either side when coming to a stop. You may have a worn damaged pad, rotor, drum, or defective, or stuck piston.
If the vehicle vibrates, and the steering wheel shakes when applying the brakes, your rotors are warped, and need to be replaced, or resurfaced.
If any of the above occur, it is time to take action, before you cause more damage to your vehicle, and put yourself and others in danger. The longer you wait to address the problem, the more expensive your repair will become.
Items to be aware of:Rotors and drums should be replaced in pairs.Always insist the rotors, drums are resurfaced when new pads are installed. Rotors, and drums are designed with extra metal thickness, They are intended to be resurfaced. Some shops will try to sell you a new drum or rotor rather than resurface your current equipment.Never re use old pads, with new or resurfaced rotors and drums.High performance pads wear quicker and often have shorter life. Low cost pads often leave unattractive brake dust on your wheels. Talk to your mechanic, and or auto parts store to determine which type of pads you are best for your application.Calipers, do not go bad very often. A bad caliper will almost always cause your vehicle to pull to the side when stopping. A new piston and seal kit for your old caliper is usually less expensive than a replacement caliper.
Routine inspection of your brakes when rotating your tires every 10,000 miles will usually find trouble before it puts a stop to your driving.
