Brake Pads
There are two brake pads on each caliper. They are
constructed of a metal "shoe" with the lining riveted or bonded to
it. The pads are mounted in the caliper, one on each side of the
rotor. Brake linings used to be made primarily of asbestos because of its
heat absorbing properties and quiet operation; however, due to health risks,
asbestos has been outlawed, so new materials are now being used. Brake
pads wear out with use and must be replaced periodically. There are many types
and qualities of pads available. The differences have to do with brake life (how
long the new pads will last) and noise (how quiet they are when you step on the
brake). Harder linings tend to last longer and stop better under heavy use but
they may produce an irritating squeal when they are applied. Technicians that
work on brakes usually have a favorite pad that gives a good compromise that
their customers can live with.
Brake pads should be
checked for wear periodically. If the lining wears down to the metal brake shoe,
then you will have a "Metal-to-Metal" condition where the shoe rubs directly
against the rotor causing severe damage and loss of braking efficiency. Some
brake pads come with a "brake warning sensor" that will emit a squealing noise
when the pads are worn to a point where they should be changed. This noise
will usually be heard when your foot is off the brake and disappear when you
step on the brake. If you hear this noise, have your brakes checked as
soon as possible.
