Replacing Brake System Parts; Brake Pedal Travel; Brake Adjustment - GMC 2003 GMT560 T-Series Owner's Manual

Four-Wheel Drum Brakes (Air Only)
The brake drums should be removed and inspected
each time the tires are removed for rotation or changing.
When you have the front brakes replaced, have the
rear brakes inspected, too.
Brake linings should always be replaced as complete
axle sets.

Brake Pedal Travel

See your dealer if the brake pedal does not return to
normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.

Brake Adjustment

Every time you make a brake stop, your brakes adjust
for wear.
Four-Wheel Disc Brakes
(Hydraulic Only)
Your vehicle has four-wheel disc brakes.
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.
Brake linings should always bereplaced as complete
axle sets.

Replacing Brake System Parts

The braking system on a vehicle is complex. Its many
parts have to be of top quality and work well together if
the vehicle is to have really good braking. Your
vehicle was designed and tested with top-quality GM
brake parts. When you replace parts of your braking
system — for example, when your brake linings
wear down and you need new ones put in — be sure
you get new approved GM replacement parts. If
you don't, your brakes may no longer work properly. For
example, if someone puts in brake linings that are
wrong for your vehicle, the balance between your front
and rear brakes can change — for the worse. The
braking performance you've come to expect can change
in many other ways if someone puts in the wrong
replacement brake parts.
Air Brake Systems
If your vehicle has air brakes, it is important to get rid of
moisture in your system. Moisture will damage your
system if it isn't removed daily.
There are two ways to do this. One is automatic if your
air-brake vehicle has the optional moisture ejector. If
your vehicle doesn't have that option, you must drain the
air reservoirs everyday.
Drain them at full system pressure. To be sure you're at
full pressure, check your air pressure gage. It should
read at least 100 psi (692 kPa).
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