Peterbilt 320 User manual

MODEL 320
OPERATOR’S
MANUAL

California
Proposition 65 Warning
•Diesel engine exhaust and some of its constituents are
known to the State of California to cause cancer, birth
defects, and other reproductive harm.
•Other chemicals in this vehicle are also known to the
State of California to cause cancer, birth defects or
other reproductive harm.
•Battery posts, terminals, and related accessories con-
tain lead and lead compounds, chemicals known to the
State of California to cause cancer and reproductive
harm. Wash hands after handling.
Quick Table of Contents
•Introduction............................................ 1
•Cab, Frame Access, & Cab Ladder........... 5
•Getting To Your Engine................................. 8
•Controls And Displays ................................... 12
•Seat And Restraint Systems............................. 49
•Driver’s Checklists................................................ 58
•Starting And Operating The Vehicle........................ 62
•Maintenance and Service........................................... 96
•Vehicle Identification.................................................... 166
•Consumer Information .................................................... 167
•Subject Index ............................................................ 169

PART 1: INTRODUCTION
PB1319 (CAT. NO. 5296 ) —1— 22-01691 (R02/02)
This manual contains useful information for the safe and efficient
operation of your Model 320. It also provides information on main-
taining your vehicle in the best condition, with an outline for perform-
ing safety checks and basic preventive maintenance inspections.
We have tried to present the information you’ll need to learn about
your vehicle’s functions, controls, and operation - and to present it as
clearly as possible. We hope you’ll find this manual easy to use.
There will be times when you need to take this manual out of your
Peterbilt. When you do, please be sure to return it to the cab when
you are finished using it. That way it will be there when you need it
the next time or when you pass the vehicle on to the next user.
Your Model 320 may not have all the features or options mentioned in
this manual. Therefore, you should pay careful attention to the
instructions that pertain to just your vehicle. In addition, if your vehicle
is equipped with special equipment or options not discussed in this
manual, consult your dealer or the manufacturer of the equipment.
All information contained in this manual is based on the latest produc-
tion information available at the time of publication. Peterbilt Motors
Company reserves the right to make changes at any time without
notice.
Warnings
We’ve put a number of warning messages in this manual. They are
there for your protection and information. Please read them and fol-
low them. They can help you to avoid injury to yourself & your pas-
sengers as well as to prevent costly damage to your vehicle. We’ve
used certain symbols and “signal words” to indicate what kind of mes-
sage is going to follow. When you see these symbols & words, you
know that you need to pay special attention. Please don’t ignore any
of these signals.
When you see this symbol & word, the message that follows is espe-
cially vital. This signals something that can cause serious injury or
death. This message will tell you what the hazard is, what can hap-
pen if you don’t heed the warning, and how to avoid it. For example:
WARNING!
WARNING! Attempting repair work without sufficient
training, service manuals, and the proper tools can be
dangerous. You could be injured or you could make
your vehicle unsafe. Do only those tasks you are fully
qualified to do.

PART 1: INTRODUCTION
PB1319 (CAT. NO. 5296 ) —2— 22-01691 (R02/02)
This symbol & word signals something that could damage your vehi-
cle. And you might receive an injury, too. For example:
Gives you information we feel you’d like to have. It could have to do
with care of your vehicle or with driving more efficiently:
Please take the time to read these messages when you see them.
And remember:
WARNING! Something that could injure you seriously.
CAUTION: Something that could cause injury to you or your
vehicle.
NOTE: Useful information
Vehicle Safety
Make sure your Peterbilt is in top working condition before heading out on
the road—it is the
responsible driver's duty to do so. Inspect the vehicle
according to PART 6: DRIVER’S CHECKLIST.
Please remember, this manual is not a training manual. It cannot tell
you everything you need to know about driving your Peterbilt vehicle.
For that you need a good training program or truck driving school. If
CAUTION:
CAUTION: Continuing to operate a vehicle with insuf-
ficient oil pressure will cause serious engine damage.
NOTE:
NOTE: A cold compressor can cause refrigerant to liquefy
and warp the valve plates or cause a hydraulic lock. Warm
the engine before starting the air conditioner.
WARNING! Do not drink and drive. Your reflexes, percep-
tions, and judgment can be affected by even a small
amount of alcohol. You could have a serious—or even fatal
accident—if you drive after drinking. Please do not drink
and drive or ride with a driver who has been drinking.
WARNING! The use of alcohol, drugs, and certain medica-
tions will seriously impair perception, reactions, and driv-
ing ability. These circumstances can substantially increase
the risk of an accident and personal injury.

PART 1: INTRODUCTION
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you have not been trained, get the proper training before you drive.
Only qualified drivers should drive this vehicle.
Every new Peterbilt vehicle is designed to conform to all Federal
Motor Vehicle Safety Standards applicable at the time of manufacture.
However, even with these safety features, continued safe and reliable
operation depends greatly upon regular vehicle maintenance. The
vehicle must be operated within the range of its mechanical capabili-
ties and the limits of its load ratings. See the axle and tire load rating
information located on the driver’s door jamb.
How to Find What You Want
There are several tools built into this manual to help you find what you
need quickly and easily.
First is the Quick Table of Contents. Located at the front of the
manual, this lists the main subjects covered and gives page numbers
where you can find these subjects. Use the Quick Table of Contents
to find information on a large subject like “Maintenance.”
Cross-referenced Citations also help you get the information you
need. If some other part of the manual contains further information
on the subject you are reading about, we’ll indicate that in a cross-ref-
erence like this: (See PART 6: DRIVER’S CHECKLIST). You won’t
have to go searching for more information.
Finally you’ll find a helpful Subject Index. It’s in the back of the man-
ual and alphabetically lists the subjects covered. So if you want infor-
mation on brakes, for example, just look under Brake in the Subject
Index. You’ll find all the pages listed where brakes or braking are dis-
cussed.
A Special Word about Repairs
Your Peterbilt dealer’s service center is the best place to have your
vehicle repaired. You can find Peterbilt dealers all over the country
with the equipment and trained personnel to get you back on the road
quickly - and keep you there.
Your vehicle is a complex machine. Anyone attempting repairs on it
needs good mechanical training and the proper tools. If you are sure
you have these requirements, then you can probably perform some
repairs yourself. However, all warranty repairs must be performed by
an authorized Peterbilt service facility. If you aren’t an experienced
mechanic, or don’t have the right equipment, please leave all repairs
to an authorized service facility. They are the ones equipped to do
the job safely and correctly.

PART 1: INTRODUCTION
PB1319 (CAT. NO. 5296 ) —4— 22-01691 (R02/02)
Maintenance Manuals. If you do decide to do any complex repair
work, you’ll need the Peterbilt Maintenance manuals. Order them
from your authorized dealer. Please provide your Chassis Serial
Number when you order, to be sure you get the correct manuals for
your vehicle. Allow about four weeks for delivery. There will be a
charge for these manuals.
Final Chassis Bill of Material. A complete, nonillustrated computer
printout listing of the parts used to custom-build your Peterbilt vehicle
is available through the Peterbilt dealer from whom your purchased
your vehicle.
Additional Sources of Information
Operator’s manuals are also supplied by the manufacturers of compo-
nents such as the engine, seats, transmission, and radio in your
Peterbilt. If you are missing any of these manuals, ask your Peterbilt
dealer to supply them.
Your new Peterbilt also contains a copy of the Truck Driver’s Hand-
book, published by the American Trucking Association. Refer to it for
important information on driving your vehicle. Another place to learn
more about trucking is a local truck driving school. Contact one near
you to find out what kinds of instruction it offers.
Federal and state agencies also have information you can ask for.
The Interstate Commerce Commission can give you information
about regulations governing transportation across state lines. And
various agencies in state governments are sources for regulations
which differ from state to state.
WARNING! Attempting repair work without sufficient
training, service manuals, and the proper tools can be
dangerous. You could be injured or you could make
your vehicle unsafe. Do only those tasks you are fully
qualified to do.
WARNING! Modifying your vehicle can make it unsafe.
Some modifications can affect your truck’s electrical
system, stability, or other important functions. Before
modifying your vehicle, check with your dealer to make
sure it can be done safely.

PART 2: GETTING INTO AND OUT OF THE CAB,
FRAME ACCESS, AND CAB LADDERiii
PB1319 (CAT. NO. 5296 ) —5— 22-01691 (R02/02)
Be careful whenever you get into or out of your vehicle’s cab. Always
maintain at least three points of contact with your hands on the grab
handles and your feet on the steps.
The pictures below show the best way to enter and exit a Model 320.
Three points of contact as you Three points of contact as you
begin climb up or down
Three points of contact as you
step in or out
WARNING! Jumping out of the cab or getting into the
cab without proper caution is dangerous. You could slip
and fall, possibly suffering a serious injury. Keep steps
clean. Clean any fuel, oil, or grease off of the steps
before entering the cab. Use the steps and grab han-
dles provided, and always keep at least three points of
contact between your hands and feet and the truck.
Look where you are going.
02871 02872
02873

PART 2: GETTING INTO AND OUT OF THE CAB,
FRAME ACCESS, AND CAB LADDER
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Door Lock and Keys
Doors can be locked from the inside by using the lock button. Close
the door then push the button down to lock. Doors automatically
unlock when you open them from the inside, and can be locked from
the outside with a key only.
To lock or unlock the doors from outside the cab, insert the key in the
lock. Turn the key toward the rear to lock; forward to unlock.
Climbing Onto the Deck Plate
WARNING! To lessen the chance and/or severity of per-
sonal injury in case of an accident, always lock the
doors while driving. Along with using the lap/shoulder
belts, properly locking the doors helps prevent occu-
pants from being thrown from the vehicle.
WARNING!
• If there is no deck plate, or if proper steps and grab
handles aren’t provided, don’t climb onto the area
behind the cab. Peterbilt did not intend for an area to
be a step if handrails or proper steps are not provided.
• You could fall and injure yourself if you step onto a
fuel tank surface. A fuel tank is not a step. The tank
surface can get very slippery, and you might not be
able to prevent a fall. Don’t step onto the surface of a
fuel tank. Use only the steps and handholds provided,
not chain hooks, etc.
• You can be hurt if you aren’t careful climbing onto and
off the deck plate. You can slip and fall, especially if
the surfaces are wet or icy, or if you step in oil, fuel, or
grease. Keep steps clean. When you are climbing
onto and off the deckplate, always maintain at least
three points of contact with your hands on the grab
handles and your feet on the steps.
NOTE: Any alteration (adding bulkheads, headache racks,
tool boxes, etc.) behind the cab or sleeper that affects the
utilization of grab handles, deck plates, or frame access
steps installed by Peterbilt must comply with FMCSR 399.

PART 2: GETTING INTO AND OUT OF THE CAB,
FRAME ACCESS, AND CAB LADDERiii
PB1319 (CAT. NO. 5296 ) —7— 22-01691 (R02/02)
Front Cab Guard/Ladder
Front Cab Guard/Ladder
The optional front cab guard/ladder is used on front-loading refuse
vehicles to protect the cab from damage and to stand on in order to
remove debris from above the cab.
WARNING!
• Do not climb on the cab roof. The cab roof is not a
slip-resistant surface and is not equipped with hand-
holds. A slip and fall could cause serious injury.
• Do not step or stand on the top rung of the ladder.
This is not a step; it is meant to be used only as a
handhold. You could slip or fall and injure yourself if
you use it as a step.

PART 3: GETTING TO YOUR ENGINE
PB1319 (CAT. NO. 5296 ) —8— 22-01691 (R02/02)
Cab Tilting
Raising the Cab
An independent hydraulic system raises and lowers the cab. A posi-
tive, dual-locking device ensures safety and eliminates danger of mis-
haps while driving.
The following cab tilting instructions are labelled and installed on the
base of the companion seat:
WARNING! You can be seriously injured by the cab if
you do not follow safety precautions. Whenever you
raise, lower, or work under the cab, please remember
the following safety rules:
• Be sure no one is under the front of the cab. Whether
you are raising or lowering the cab, KEEP CLEAR.
• Perform work only with the cab in the full tilt position
with the locking bar engaged.
• To avoid possible damage or serious injury
- Never allow a cab door to fall open with the cab tilted.
- Never use a cab door to support your weight with the
cab tilted.
• When a cab hydraulic system needs service or repair:
- Have maintenance and repair done only by someone
qualified in hydraulic systems.
- Be sure no one tries to bleed the system with the cab
raised. This will defeat the safety system. The cab
can fall and crush anyone under it.
- Never work under a raised cab unless it is properly
supported. This means using an overhead hoist of
sufficient capacity to support the cab safely. Never
prop the cab up instead of using a hoist. The prop
could fail and let the cab fall on you or anyone else
working under it.
- Do not tamper with any part of the cab tilt cylinders,
including removing the velocity fuses. To do so will
defeat their purpose. The cab could fall and crush
anyone under it. If you have any need for repair
involving the velocity fuses, have a qualified truck
mechanic do the work.
NOTE: In case of oil loss in the system or a lock-up in the tilt
cylinders, refer to the maintenance manual for repair instruc-
tions.