Pontiac 1997 Grand Am Owner's Manual page 260

Brake Wear
Your Pontiac has front disc brakes and rear drum brakes.
Disc brake pads have built-in wear indicators that make a
high-pitched warning sound when the brake pads are worn
and new pads are needed. The sound may come and go or
be heard all the time your vehicle is moving (except when
you are pushing on the brake pedal firmly).
The brake wear warning sound means that soon
your brakes won't work well. That could lead to
an accident. When you hear the brake wear
warning sound, have your vehicle serviced.
I
NOTICE:
Continuing to drive with worn-out brake pads
could result in costly brake repair.
Some driving conditions or climates may cause a brake
squeal when the brakes are first applied or lightly
applied. This does not mean something is wrong with
your brakes.
See "Caliper/Knuckle Maintenance Inspection" in
Section 7 of this manual under Part C "Periodic
Maintenance Inspections."
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly torque wheel nuts in the
proper sequence to GM specifications.
Your rear drum brakes don't have wear indicators, but if
you ever hear a rear brake rubbing noise, have the rear
brake linings inspected. Also, the rear brake drums
should be removed and inspected each time the tires are
removed for rotation or changing. When you have the
front brake pads replaced, have the rear brakes
inspected, too.
Brake linings should always be replaced as complete
axle sets.
See "Brake System Inspection" in Section 7 of this
manual under Part C "Periodic Maintenance
Inspections".
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