Notice:Holding your key in START for longer
than 15 seconds at a time will cause your
battery to be drained much sooner. And the
excessive heat can damage your starter motor.
Notice:If the wait to start light stays on
after starting your vehicle, your vehicle may
not run properly. Have your vehicle serviced
right away.
3. If the engine does not start after 15 seconds
of cranking, turn the ignition key to OFF. Wait
one minute for the starter to cool, then try
the same steps again.
If you are trying to start your engine after you
have run out of fuel, seeRunning Out of Fuel
on page 262.
When your engine is cold, let it run for a few
minutes before you move your vehicle. This lets
oil pressure build up. Your engine will sound louder
when it is cold.
Notice:If you are not in an idling vehicle and
the engine overheats, you would not be there to
see the overheated engine indication. This
could damage your vehicle. Do not let your
engine run when you are not in your vehicle.Cold Weather Starting
If your vehicle has the 6.6L DURAMAX®Diesel
Engine and the Isuzu 6H Diesel Engine, the
following notice applies:
Notice:Your diesel engine has an electric air
intake heater system which reduces white
smoke and helps start the engine in cold
weather. Do not spray starting uid into the air
intake where it can contact the heater elements.
If you do not have the GM Automatic Ether
Injection System, do not use starting uid or
you could damage your engine. If you have the
GM system, use only GM approved starting
uid that has been tested to establish
compatibility with the air inlet heater system.
101
If the light does not come on when the engine is
cold, your vehicle needs service.
If your batteries do not have enough charge to
start your engine, seeBattery on page 304.
Be sure you have the right oil for your engine, and
that you have changed the oil at the proper
times. If you use the wrong oil, your engine may
be harder to start.
Be sure you are using the proper fuel for existing
weather conditions. SeeWhat Fuel to Use on
page 253.
If the engine starts, runs a short time, then stops,
your vehicle needs service.
{CAUTION:
Do not use gasoline or starting aids, such
as ether, in the air intake. They could
damage your engine. There could also be
a re, which could cause serious personal
injury.
Engine Alarm and Automatic
Shutdown
Your check gages warning light will come on if the
system senses high engine temperature or low
engine oil pressure. If high engine temperature or
low engine oil pressure is detected, you will
also hear a tone alarm at two beats per second.
The alarm and the light will remain on until
the condition is fixed. If the engine temperature or
oil pressure condition worsens, the tone alarm
will go to five beats per second.
If the system senses low engine coolant, the
five beat per second alarm and the low coolant
warning light will come on.
The five beats per second tone alarm means that
your engine will shut down in about 25 to
30 seconds. There is also an engine shutdown
light to indicate that the engine will shut down. See
Engine Shutdown Warning Light on page 177.
104
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
138
Loading Your Vehicle
It is the responsibility of the Final Stage
manufacturer to install a Certification label on
your vehicle. This label shows how much weight
your vehicle can properly carry. It may also
show the size of the vehicle’s original tires, and
the inflation pressures needed to obtain the
gross weight capacity of your vehicle. This is
called the Gross Vehicle Weight Rating (GVWR).
The tire information could also be shown on a
separate Tire Information label.
The GVWR includes the weight of the vehicle,
all occupants, fuel, and cargo.
The Certification label also tells you the maximum
weight for the front and rear axles, called the
Gross Axle Weight Rating (GAWR). To find out
the actual loads on your front and rear axles,
go to a weigh station and weigh your vehicle.
Your dealer can help you with this. Be sure
to spread out your load equally on both sides
of the center line.Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
And, if you do have a heavy load, spread it out.
{CAUTION:
Do not load your vehicle any heavier than
the Gross Vehicle Weight Rating (GVWR),
or either the maximum front or rear Gross
Axle Weight Rating (GAWR). If you do,
parts on your vehicle can break, and it
can change the way your vehicle handles.
These could cause you to lose control
and crash. Also, overloading can shorten
the life of your vehicle.
238
Service........................................................ 248
California Proposition 65 Warning.............. 248
Doing Your Own Service Work.................. 249
Engine Fan Breakage................................ 250
Fuel............................................................. 251
Gasoline Octane........................................ 251
Gasoline Specifications.............................. 251
Additives................................................... 252
Diesel Engine Fuel.................................... 253
What Fuel to Use...................................... 253
Very Cold Weather Operation.................... 256
Water in Fuel............................................ 256
Running Out of Fuel.................................. 262
Fuel Filter Replacement............................. 263
Fuels in Foreign Countries........................ 264
Filling the Tank......................................... 264
Filling a Portable Fuel Container............... 266Checking Things Under the Hood.............. 266
Hood Latches............................................ 267
Engine Oil (Caterpillar
®Diesel Engine)...... 268
Engine Oil (Gasoline Engine).................... 268
Engine Oil (DURAMAX
®/Isuzu Diesel
Engine).................................................. 272
Engine Oil Life System
(Gasoline Engine).................................. 276
Engine Oil Life System
(DURAMAX
®Diesel)............................... 278
Engine Oil Life System
(Caterpillar
®Diesel Engine).................... 279
Engine Air Cleaner/Filter............................ 280
Automatic Transmission Fluid.................... 282
Manual Transmission Fluid........................ 283
Engine Coolant (Gas and
DURAMAX
®/Isuzu Engines).................... 284
Engine Coolant (Caterpillar®Diesel
Engines)................................................ 287
Coolant Surge Tank Pressure Cap............ 288
Section 5 Service and Appearance Care
245
Engine Overheating................................... 288
Cooling System (Gas and
DURAMAX
®/Isuzu Engines).................... 290
Engine Fan Noise..................................... 294
Power Steering Fluid................................. 295
Windshield Washer Fluid........................... 296
Brakes...................................................... 297
Battery...................................................... 304
Jump Starting............................................ 305
Rear Axle.................................................... 311
Rear Axle Shift Motor................................ 312
Four-Wheel Drive........................................ 312
Front Axle................................................... 313
Noise Control System................................. 314
Tampering with Noise Control System
Prohibited.............................................. 314
Bulb Replacement....................................... 315
Windshield Wiper Blade Replacement....... 316Other Service Items.................................... 317
Fuel Filter.................................................. 317
Primary Fuel Filter and Water Separator...... 317
Secondary Fuel Filter and Water
Separator/Heater (Caterpillar
®Diesel)...... 318
Automatic Ether Injection System
(Caterpillar
®Diesel)................................ 318
Front Wheel Bearings with
Oil-Filled Hubs....................................... 319
Air Conditioning System............................ 320
Tires............................................................ 321
Inflation - Tire Pressure............................. 322
Wheel Loading.......................................... 323
Dual Tire Operation................................... 323
When It Is Time for New Tires.................. 324
Wheel Alignment and Tire Balance............ 324
Tightening the Wheel Nuts........................ 325
Wheel Replacement.................................. 328
If a Tire Goes Flat.................................... 330
Section 5 Service and Appearance Care
246
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
Other Service Items
Fuel Filter
Fuel Filter/Pressure Regulator
(Gasoline Engines)
The steel fuel filter/pressure regulator is located
near the engine compartment on the driver’s
side frame rail. If your vehicle has a rear steel fuel
tank, the fuel filter/pressure regulator is located
near the rear fuel tank, on the driver’s side frame
rail. SeeScheduled Maintenance on page 363
for recommended service intervals.
If your vehicle is equipped with the optional Davco
spin-on type filter, it is located on the driver’s
side frame rail.
Fuel Filter (Diesel Engines)
If you have a diesel engine, your fuel filter is
located in the engine compartment on the driver’s
side of the vehicle, or along the driver’s side
frame rail. See “Fuel Filter Replacement” earlier in
this section for further information.
Also seeScheduled Maintenance on page 363for
recommended service intervals.
Primary Fuel Filter and Water
Separator
If you have a diesel
engine, you may have
this spin-on filter. It
is located on the driver’s
side frame rail.
It has a clear plastic drain bowl at the bottom.
Check the drain bowl occasionally for any water or
particles.
To drain the bowl, do the following:
1. Shut off the engine.
2. Partially open the drain valve at the bottom of
the filter.
SeeEngine Oil (Caterpillar
®Diesel Engine) on
page 268orEngine Oil (Gasoline Engine) on
page 268orEngine Oil (DURAMAX
®/Isuzu Diesel
Engine) on page 272for proper disposal
procedures.
317