Your Driving, the Road, and Your Vehicle..........4-2
Defensive Driving...........................................4-2
Drunken Driving.............................................4-2
Control of a Vehicle........................................4-5
Braking.........................................................4-6
Trailer Brake Hand Control Valve......................4-9
Inter-Axle Differential Lock Control...................4-10
Rear Axle Differential Lock Control..................4-10
Traction Control System (TCS).......................4-11
Steering......................................................4-12
Off-Road Recovery.......................................4-14
Passing.......................................................4-14
Loss of Control.............................................4-16
Driving at Night............................................4-17Driving in Rain and on Wet Roads..................4-18
City Driving..................................................4-21
Freeway Driving...........................................4-22
Highway Hypnosis........................................4-23
Hill and Mountain Roads................................4-23
Winter Driving..............................................4-25
If You Are Stuck: In Sand, Mud,
Ice or Snow..............................................4-29
Towing..........................................................4-31
Towing Your Vehicle.....................................4-31
Loading Your Vehicle....................................4-33
Trailer Connections (C4/C5 Models Only).........4-35
Power Take-Off (PTO)...................................4-36
Section 4 Driving Your Vehicle
4-1
Rocking Your Vehicle To Get It Out
First, turn your steering wheel left and right. That will
clear the area around your front wheels. If your vehicle
has traction control, you should turn the traction
control system off. SeeTraction Control System (TCS)
on page 4-11. Then shift back and forth between
REVERSE (R) and a forward gear (or with a manual
transmission, between FIRST (1) or SECOND (2)
and REVERSE (R)), spinning the wheels as little as
possible. Release the accelerator pedal while you shift,
and press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning your wheels
in the forward and reverse directions, you will cause
a rocking motion that may free your vehicle. If that does
not get you out after a few tries, you may need to be
towed out. If you do need to be towed out, seeTowing
Your Vehicle on page 4-31.
Using the Tow Hooks
If your vehicle has tow hooks, the hooks are provided at
the front and, on some models, the rear of your
vehicle. You may need to use them if you are stuck
off-road and need to be pulled to some place where you
can continue driving.
4-30
{CAUTION:
These hooks, when used, are under a lot of
force. Always pull the vehicle straight out.
Never pull on the hooks at a sideways angle.
The hooks could break off and you or others
could be injured from the chain or cable
snapping back.
Notice:Never use tow hooks to tow the vehicle.
Your vehicle could be damaged and it would not be
covered by warranty.
Towing
Towing Your Vehicle
Consult your dealer or a professional towing service if
you need to have your disabled vehicle towed. See
Roadside Assistance Program on page 7-4.
Releasing Air-Operated Parking Brakes
If your vehicle has air brakes, you could have a
special towing problem. If your vehicle has to be towed
because of a complete loss of air pressure from
both systems, the parking brakes will have automatically
engaged. The tow operator can release the brakes
manually by using the following steps. Then your vehicle
can be towed with all wheels or only the rear wheels
on the ground.
1. Block the wheels of the vehicle.
4-31
Trailer Connections
(C4/C5 Models Only)
Heavy-Duty Trailer Wiring Package
Your vehicle may be equipped with an eight-wire trailer
towing harness. This harness, with a seven-pin
universal heavy-duty trailer connector, is attached to a
bracket on the platform hitch.
The Center High-Mounted Stoplamp (CHMSL) wire is
tied next to the trailer wiring harness for use with a
trailer.The eight-wire harness contains the following trailer
circuits:
•Yellow: Left Stop/Turn Signal
•Dark Green: Right Stop/Turn Signal
•Brown: Taillamps
•White: Ground
•Light Green: Back-up Lamps
•Light Blue: CHMSL
•Red: Battery Feed
•Dark Blue: Trailer Brake
4-35
Trailer Connections
(C7/C8 Models Only)
If your vehicle has these trailer connections, they are
located at the rear of the cab for a tractor and at the rear
of the chassis when towing a trailer. There will be an
air connection and an electrical connection.
Be sure that the couplings to the trailer are made
correctly.
Air Connections
If you are not connecting the trailer air line connections
to another piece of equipment, be sure to replace
their protective caps.
Electrical Connections
This system is a seven-wire cable that will connect to
the trailer, supplying power to the trailer’s lighting
system. When not in use, it is stored in the trailer
air-hose storage bracket.
Power Take-Off (PTO)
If your vehicle is equipped
for the addition of a PTO,
this factory installed
switch will be located in
the instrument panel
switchbank.
Before using a PTO, refer to the manufacturer’s or
installer’s instructions.
4-36
5. Then replace the
pressure cap. Be sure
the pressure cap is
hand-tight and
fully seated.
Engine Fan Noise
Your vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as thetransmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
See your Maintenance Schedule for when to check your
power steering fluid.
How To Check Power Steering Fluid
Check your power steering fluid only when the engine is
warm. If the engine isn’t warm, you probably won’t
get an accurate reading.
If the fluid level is between the MIN and MAX marks,
you have enough. If you need fluid, add only enough of
the proper fluid to bring it in between the MIN and
MAX marks.
5-43
United States
GM Medium Duty Truck
Customer Assistance Center
P.O. Box 44947
Detroit, MI 48244
1-800-TO-CHEVY (1-800-862-4389)
1-800-833-2438 (For Text Telephone devices (TTYs))
Roadside Assistance: 1-800-TO-CHEVY
Fax Number: 313-381-0022
From Puerto Rico:
1-800-496-9992 (English)
1-800-496-9993 (Spanish)
Fax Number: 313-381-0022
From U.S. Virgin Islands:
1-800-496-9994
Fax Number: 313-381-0022
Canada
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
1-800-263-3777 (English)
1-800-263-7854 (French)
1-800-263-3830 (For Text Telephone devices (TTYs))
Roadside Assistance: 1-800-268-6800
All Overseas Locations
Please contact the local General Motors Business Unit.
Mexico, Central America and
Caribbean Islands/Countries (Except
Puerto Rico and U.S. Virgin Islands)
General Motors de Mexico, S. de R.L. de C.V.
Customer Assistance Center
Paseo de la Reforma # 2740
Col. Lomas de Bezares
C.P. 11910, Mexico, D.F.
01-800-508-0000
Long Distance: 011-52-53 29 0 800
Roadside Assistance Program
GM Medium Duty Truck’s Roadside Assistance provides
stranded owners with towing service for disabled
vehicles during the base warranty period. This service
combines the efforts of trained telephone representatives
with a network of GM Medium Duty Truck’s dealer
services.
7-4
Storage Areas................................................2-41
Center Console Storage Area........................2-42
Stuck in Sand, Mud, Ice or Snow......................4-29
Sun Visors.....................................................2-10
Switchbanks, Instrument Panel..........................3-16
T
Tachometer....................................................3-26
Theft-Deterrent, Radio.....................................3-57
Theft-Deterrent Systems...................................2-10
Tilt Wheel........................................................ 3-7
Tire Inflation Check.........................................6-24
Tires.....................................................5-68, 5-82
Changing a Flat Tire....................................5-76
Dual Tire Operation.....................................5-69
If a Tire Goes Flat.......................................5-75
Inflation - Tire Pressure................................5-68
Rims and Wheels........................................5-69
Tightening the Wheel Nuts............................5-71
Wheel Alignment and Tire Balance.................5-70
Wheel Replacement.....................................5-74
When It Is Time for New Tires......................5-70
To Use the Engine Coolant Heater....................2-24
Top Strap......................................................1-38
Towing
Power Take-Off (PTO)..................................4-36
Your Vehicle...............................................4-31Traction
Control System (TCS)..................................4-11
Tractor Protection (Breakaway) Valve Check.......6-28
Trailer
Connections................................................4-35
Trailer Brake Hand Control Valve........................ 4-9
Trailer Connections
(C7/C8 Models Only)...................................4-36
Transmission
Fluid, Automatic...........................................5-31
Fluid, Manual..............................................5-32
Service Warning Light..................................3-31
Temperature Gage.......................................3-40
Transmission Fluid Capacity.............................5-98
Transmission Operation, Automatic....................2-28
Transmission Operation, Manual........................2-30
Trip Odometer................................................3-25
Turn and Lane-Change Signals.......................... 3-8
Turn Signal/Multifunction Lever........................... 3-7
Two-Speed Rear Axle......................................2-33
Two-Speed Rear Axle Electric Shift Control.........2-26
U
Underbody Flushing Service.............................6-28
Underbody Inspection......................................6-28
Underhood Fuse Block....................................5-91
Understanding Radio Reception........................3-57
14