MODEL 330 OPERATOR'S MANUAL - Peterbilt Motors Company

Preventive Maintenance
BRAKE SYSTEM
If your truck has an air brake system, see the pages below.
If your truck has a hydraulic brake system, please go to
“Hydraulic Brake System” on page 157.
Introduction
To operate your vehicle safely, you need some understanding
of its brake systems. Brake adjustment and brake balance
must be set carefully to allow equal stopping forces at all
wheels. Tires are also a very important part of the whole system.
How fast you can stop depends on how much friction
there is between the road and your tires.
All of the following areas are interrelated and must conform
to original specifications:
• tire size
• wedge angle
• brake linings
• slack adjusters
• cam radius
• drum radius
• brake chambers
Brake System
Once a brake system is set to specifications, changing any
one of its components or any combination of components
may degrade the system. All parts have to work together to
perform as they should.
Because your brake system is air operated, see the following
section “Air System” on page 163 for more information on
checking your brakes.
Any replacement components in the brake system should be
the same or better than the original components. Any
changes from the original specifications can affect the performance
of the entire system.
WARNING! Do not use any replacement part in
the brake system unless it conforms exactly to
original specifications. A nonconforming part in
your vehicle’s brake system could cause a malfunction
resulting in an injury accident. Sizes
and types are so related to one another that a
seemingly unimportant change in one may
result in a change in how well the brakes work
for you on the road. If parts do not work together
properly, you could lose control of your vehicle,
which could cause a serious accident.
Model 330 PB1318 3/01 – 153 –