Page 138 of 430

Engine Coolant Temperature Gage............ 173
Low Coolant Warning Light....................... 173
Wait to Start Indicator............................... 174
Malfunction Indicator Lamp........................ 174
Oil Pressure Gage..................................... 175
Low Oil Level Light................................... 176
Change Engine Oil Light........................... 176
Engine Overspeed Warning Light.............. 177
Engine Shutdown Warning Light................ 177
Transmission Temperature Gage............... 178
Exhaust Brake Indicator Light.................... 178
Differential Lock Indicator Light.................. 178
Reduced Engine Power Light.................... 179
Highbeam On Light................................... 179
Daytime Running Lamps (DRL)
Indicator Light........................................ 179
Low Washer Fluid Warning Light............... 180
Check Gages Warning Light...................... 180
Fuel Gage................................................. 181Water in Fuel Warning Light...................... 182
Air Filter Restriction Indicator..................... 182
Air Pressure Gage..................................... 183
Hourmeter Gage........................................ 183
Audio System(s)......................................... 184
Setting the Time........................................ 185
AM-FM Radio............................................ 186
Radio with Cassette.................................. 189
Radio with CD........................................... 195
Theft-Deterrent Feature
(Non-RDS Radios)................................. 201
Radio Reception........................................ 201
Care of the Cassette Tape Player............. 202
Care of Your CDs..................................... 203
Care of the CD Player.............................. 204
Fixed Mast Antenna.................................. 204
Chime Level Adjustment............................ 204
Section 3 Instrument Panel
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Engine Coolant Temperature Gage
This gage shows the engine coolant temperature.
If the gage pointer moves into the red area,
your engine coolant might have overheated and
your engine may be too hot. You should pull off the
road, stop your vehicle and turn off the engine
as soon as possible.
SeeEngine Overheating on page 288. If you have
a Caterpillar
®diesel engine, also see your
Caterpillar®Operation & Maintenance Manual.
Low Coolant Warning Light
You have a low coolant
warning light. If this light
comes on, your system
is low on coolant and the
engine may overheat.
The warning light should come on briefly, as a
check, when you turn on the ignition.
When it comes on, you will also hear a warning
tone at several beats per second for 10 seconds.
SeeEngine Coolant (Gas and DURAMAX
®/Isuzu
Engines) on page 284orEngine Coolant
(Caterpillar
®Diesel Engines) on page 287and
have your vehicle serviced as soon as you can.
This light may also come on if your vehicle is
equipped with the automatic engine shutdown
system and engine shutdown has begun.
SeeEngine Alarm and Automatic Shutdownunder
Starting the Diesel Engine on page 100.
United StatesCanada
173
Page 180 of 430
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 296.
Check Gages Warning Light
This light will come on
as you’re starting the
engine, just as a check.
If this light comes on and stays on while you are
driving. It means that either your engine coolant
temperature gage or your 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
equipped with the optional automatic engine
shutdown system and engine shutdown has
begun. SeeEngine Alarm and Automatic
ShutdownunderStarting the Diesel Engine on
page 100.
180
Page 284 of 430

Engine Coolant (Gas and
DURAMAX
®/Isuzu Engines)
The cooling system in your vehicle is filled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for five years or
150,000 miles (240 000 km), whichever occurs
first, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 288.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
•Give freezing protection down to
−34°F (−37°C).
•Give boiling protection up to 265°F (129°C).
•Protect against rust and corrosion.
•Help keep the proper engine temperature.
•Let the warning lights and gages work as
they should.
Notice:Using coolant other than
DEX-COOL
®may cause premature engine,
heater core or radiator corrosion. In addition,
the engine coolant may require changing
sooner, at 30,000 miles (50 000 km) or
24 months, whichever occurs rst. Any
repairs would not be covered by your
warranty. Always use DEX-COOL
®
(silicate-free) coolant in your vehicle.
284
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Coolant Surge Tank Pressure Cap
The coolant surge tank pressure cap is located in
the engine compartment, on the driver’s side of
the vehicle.
Notice:Your vehicle’s surge tank pressure cap
is designed for use with medium-duty cooling
systems only. If the surge tank pressure cap is
not tightly installed, coolant loss and possible
engine damage may occur. Be sure the cap is
properly and tightly secured.
Engine Overheating
You will find an engine coolant temperature gage,
as well as a low coolant warning light, on your
vehicle’s instrument panel. SeeEngine Coolant
Temperature Gage on page 173andLow Coolant
Warning Light on page 173for more information.
Your vehicle also has a check gages warning light
on the instrument panel. SeeCheck Gages
Warning Light on page 180for more information.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Just
turn it off and get everyone away from the
vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned.
Stop your engine if it overheats, and get
out of the vehicle until the engine is cool.
Notice:If your engine catches re because
you keep driving with no coolant, your vehicle
can be badly damaged. The costly repairs
would not be covered by your warranty.
288
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4. With the coolant surge tank pressure cap off,
start the engine and let it run until you can
feel the upper radiator hose getting hot. Watch
out for the engine cooling fan.
By this time, the coolant level inside the
coolant surge tank may be lower. If the level is
lower, add more of the proper mixture to the
coolant surge tank until the level reaches
slightly above the FULL COLD mark.
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 the
transmission 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.
294
Page 296 of 430

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.
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 uid,
follow the manufacturer’s instructions
for adding water.
Do not mix water with ready-to-use washer
uid. Water can cause the solution to
freeze and damage your washer uid tank
and other parts of the washer system.
Also, water does not clean as well
as washer uid.
Fill your washer uid tank only
three-quarters full when it is very cold.
This allows for 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
your washer system and paint.
296
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Usage Fluid/Lubricant
Engine Coolant
(Gasoline
Engine &
DURAMAX
®/
Isuzu Diesel)50/50 mixture of clean, drinkable
water and use only DEX-COOL
®
Coolant. SeeEngine Coolant (Gas
and DURAMAX®/Isuzu Engines)
on page 284orEngine Coolant
(Caterpillar
®Diesel Engines)
on page 287.
Hydraulic Brake
SystemDelco
®Supreme 11 Brake Fluid
or equivalent DOT-3 brake fluid.
Windshield
Washer SolventGM Optikleen
®Washer Solvent.
Clutch Bearing
LubricantClutch Bearing Lubricant
(GM Part No. 12378484 or
equivalent NLGI #3 consistency).
Exhaust Brake
Ball Joint Cap
LubricantHigh-Temperature Grease
(GM Part No. U.S. 1051344,
in Canada 903037) or
NLGI #3 consistency.
Usage Fluid/Lubricant
Power Steering
SystemDEXRON
®-VI Automatic
Transmission Fluid.
Manual
TransmissionSynthetic Manual Transmission
Fluid (GM Part No. U.S. 12345724,
in Canada 10953510).
Automatic
TransmissionSee the Allison Transmission
®
Operator’s Manual for correct
transmission fluid.
Key Lock
CylindersMulti-Purpose Lubricant, Superlube
(GM Part No. U.S. 12346241,
in Canada 10953474).
Chassis
LubricationChassis Lubricant
(GM Part No. U.S. 12377985,
in Canada 88901242) or lubricant
meeting requirements of NLGI #2,
Category LB or GC-LB.
398