
Vehicle Symbol Chart
Here are some additional symbols that may be found on
the vehicle and what they mean. For more information
on the symbol, refer to the index.
9:Airbag Readiness Light
#:Air Conditioning
!:Antilock Brake System (ABS)
g:Audio Steering Wheel Controls or OnStar®
$:Brake System Warning Light
":Charging System
I:Cruise Control
B:Engine Coolant Temperature
O:Exterior Lamps
#:Fog Lamps
.:Fuel Gage
+:Fuses
i:Headlamp High/Low-Beam Changer
j:LATCH System Child Restraints
*:Malfunction Indicator Lamp
::Oil Pressure
}:Power
/:Remote Vehicle Start
>:Safety Belt Reminders
7:Tire Pressure Monitor
F:Traction Control
M:Windshield Washer Fluid
iv

Low Coolant Warning Light............................3-35
Wait to Start Light........................................3-35
Malfunction Indicator Lamp.............................3-36
Oil Pressure Gage........................................3-38
Low Oil Level Light.......................................3-39
Change Engine Oil Light................................3-39
Engine Overspeed Warning Light....................3-40
Engine Shutdown Warning Light.....................3-40
Transmission Temperature Gage.....................3-40
Exhaust Brake Indicator Light.........................3-41
Differential Lock Indicator Light.......................3-41
Reduced Engine Power Light.........................3-42
Highbeam On Light.......................................3-42
Daytime Running Lamps (DRL)
Indicator Light...........................................3-42
Low Washer Fluid Warning Light.....................3-43
Power Take-Off Light (PTO)...........................3-43Check Gages Warning Light...........................3-43
Fuel Gage...................................................3-44
Water in Fuel Warning Light...........................3-45
Change Fuel Filter Warning Light....................3-45
Diesel Particulate Filter Warning Light..............3-46
Air Filter Restriction Indicator..........................3-46
Air Pressure Gage........................................3-47
Hourmeter Gage...........................................3-47
Audio System(s).............................................3-48
Setting the Clock..........................................3-48
Radio(s)......................................................3-49
Theft-Deterrent Feature..................................3-57
Radio Reception...........................................3-58
Fixed Mast Antenna......................................3-58
Chime Level Adjustment................................3-58
Section 3 Instrument Panel
3-2

For steady wiping at low speed, turn the band toward
you to the first solid band below the delay settings.
For high-speed wiping, turn the band farther, to the last
solid band below the delay settings.
Clear ice and snow from the wiper blades before using
them. If the wipers are frozen to the windshield,
carefully loosen or thaw them. If they become worn or
damaged, get new blades or blade inserts. For more
information, seeWindshield Wiper Blade Replacement
on page 5-71.
The windshield wiper motor is protected from overload
by a circuit breaker and a fuse. If the motor overheats
due to heavy snow or ice the wiper will stop until
the motor cools. Although the circuit is protected from
electrical overload, overload due to heavy snow or
ice may cause wiper linkage damage.Windshield Washer
L(Washer Fluid):There is a paddle marked with the
windshield washer symbol at the top of the multifunction
lever. Press the paddle to spray washer fluid on the
windshield. The wipers will clear the window and then
either stop or return to the preset speed.
{CAUTION:
In freezing weather, do not use your washer until
the windshield is warmed. Otherwise the washer
fluid can form ice on the windshield, blocking your
vision.
3-9

Low Washer Fluid Warning Light
This light is located above
the climate controls in the
center of the instrument
panel.
This light will come on when your vehicle is low on
windshield washer fluid.
For more information, seeWindshield Washer Fluid on
page 5-50.
Power Take-Off Light (PTO)
For vehicles with Power
Take-Off (PTO), this light
is located in the center
of the instrument panel.
This light will come on when the PTO switch is in the
ON/RUN position. SeePower Take-Off (PTO) on
page 2-30for more information.
Check Gages Warning Light
This light will come on
briefly when the engine is
started.
If this light comes on and stays on while you are driving.
It means that either the engine coolant temperature
gage or the engine oil pressure gage may be showing a
reading in the warning zone.
When the check gages light comes on, you will also
hear a warning tone. The tone and the light will
stay activated until the problem is corrected.
This light may also come on if your vehicle is has
automatic engine shutdown system and engine
shutdown has begun. SeeEngine Alarm and Automatic
Shutdown on page 2-18.
3-43

Service............................................................5-3
Accessories and Modifications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-5
Engine Fan Breakage.....................................5-6
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specifications....................................5-7
Additives.......................................................5-7
Diesel Engine Fuel.........................................5-8
What Fuel to Use...........................................5-8
Very Cold Weather Operation.........................5-11
Water in Fuel...............................................5-11
Running Out of Fuel.....................................5-17
Fuel Filter Replacement.................................5-18
Fuels in Foreign Countries.............................5-19
Filling the Tank............................................5-20
Filling a Portable Fuel Container.....................5-22
Checking Things Under the Hood....................5-22
Hood Latches...............................................5-23
Engine Oil (DURAMAX Diesel Engine).............5-24
Engine Oil (Caterpillar Diesel Engine)..............5-27
Engine Oil (Isuzu Diesel Engine).....................5-28
Engine Oil (Gasoline Engine)..........................5-32
Engine Oil Life System (Gasoline Engine)........5-35Engine Oil Life System (DURAMAX/Isuzu
Diesel Engines).........................................5-36
Engine Oil Life System (Caterpillar
Diesel Engine)..........................................5-38
Engine Air Cleaner/Filter................................5-38
Automatic Transmission Fluid.........................5-42
Manual Transmission Fluid.............................5-42
Cooling System............................................5-43
Engine Coolant (Caterpillar Diesel Engines)......5-47
Coolant Surge Tank Pressure Cap..................5-47
Engine Overheating.......................................5-48
Engine Fan Noise.........................................5-49
Power Steering Fluid.....................................5-49
Windshield Washer Fluid................................5-50
Brakes........................................................5-52
Battery........................................................5-61
Jump Starting...............................................5-62
Rear Axle.......................................................5-67
Rear Axle Shift Motor....................................5-68
Four-Wheel Drive............................................5-68
Front Axle......................................................5-69
Noise Control System.....................................5-70
Tampering with Noise Control System
Prohibited.................................................5-70
Bulb Replacement..........................................5-71
Section 5 Service and Appearance Care
5-1

How To Check Power Steering Fluid
Check your power steering fluid only when the engine is
warm. If the engine is not warm, you probably will not
get an accurate reading.
If the fluid level is between the MIN (Minimum) and
MAX (Maximum) 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.
If your power steering fluid level is low, this can cause
the brake or service brakes soon warning lights to come
on. In addition, the steering effort and emergency
brake distance could increase.
If either light remains on after you have added power
steering fluid to the proper level, then shut off the engine
for 10 seconds. This should reset the brake warning
lights. If one or both lights stay on, see “Hydraulic Brake
System Warning Lights” underBrake System Warning
Light on page 3-31for more information.
What to Use
To determine what kind of fluid to use, seePart C:
Recommended Fluids and Lubricants on page 6-31.
Notice:When adding power steering fluid or
making a complete fluid change, always use the
proper fluid. Failure to use the proper fluid can
cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washer fluid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use a fluid that has
sufficient protection against freezing.
5-50

Adding Washer Fluid
Open the cap with the
washer symbol on it.
Add washer fluid until
the tank is full.
The windshield washer fluid reservoir is located in the
engine compartment on the driver’s side of the vehicle.Notice:•When using concentrated washer fluid, follow
the manufacturer’s instructions for adding
water.
•Do not mix water with ready-to-use washer fluid.
Water can cause the solution to freeze and
damage your washer fluid tank and other parts
of the washer system. Also, water does not
clean as well as washer fluid.
•Fill the washer fluid tank only three-quarters full
when it is very cold. This allows for fluid
expansion if freezing occurs, which could
damage the tank if it is completely full.
•Do not use engine coolant (antifreeze) in your
windshield washer. It can damage the vehicle’s
windshield washer system and paint.
5-51

Part B: Owner Checks and Services
These owner checks and services should be performed
at the intervals specified to help ensure vehicle
safety, dependability, and emission control performance.
For your safety and that of others, any of the
safety-related components that may have been
damaged in an accident should be checked and any
needed repairs made before operating the vehicle.
At the minimum, these routine checks should be made
every 6 months or 6,000 miles (10 000 km), whichever
occurs first. Whenever repairs are needed, have
them completed before operating the vehicle.
At Each Fuel Fill
It is important to perform these underhood checks at
each fuel fill.
Engine Oil Level Check
Notice:It is important to check the engine oil
regularly and keep it at the proper level. Failure to
keep the engine oil at the proper level can cause
damage to the engine not covered by the vehicle
warranty.Check the engine oil level and add the proper oil if
necessary. SeeEngine Oil (DURAMAX Diesel Engine)
on page 5-24orEngine Oil (Caterpillar Diesel Engine)
on page 5-27orEngine Oil (Isuzu Diesel Engine) on
page 5-28orEngine Oil (Gasoline Engine) on page 5-32.
Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
(Caterpillar Diesel Engines) on page 5-47.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the windshield
washer fluid reservoir and add the proper fluid if
necessary. SeeWindshield Washer Fluid on page 5-50.
Tire Inflation Check
Check tire inflation cold. Make sure the tires are inflated
to the correct pressures. SeeLoading the Vehicle on
page 4-20andInflation - Tire Pressure on page 5-77.
6-26