Ignition Positions
With your key in the ignition switch, you can turn it to
five different positions.
A (ACCESSORY):This position allows you to use
things like the radio, power windows and the windshield
wipers when the engine is off. To get into ACCESSORY,
push in the key and turn it toward you. Your steering
wheel will remain locked, just as it was before you
inserted the key.
B (LOCK):This position locks your ignition, steering
wheel and transmission. It is a theft-deterrent feature.
You will only be able to remove your key when the
ignition is turned to LOCK.C (OFF):This position lets you turn off the engine but
still turn the steering wheel. It does not lock the
steering wheel like LOCK. Use OFF if you must have
your vehicle in motion while the engine is off.
D (RUN):This is the position for driving.
E (START):This position starts your engine.
Engine Starter Over-Crank
Protection
Your vehicle may have an engine starter over-crank
protection system. If the starter motor overheats and
shuts off due to over-cranking, the motor must cool down
before it will reset and allow starter operation. It can take
up to six minutes before the starter will work again.
Starting the Gasoline Engine
Engines start differently. The 8th digit of your Vehicle
Identification Number (VIN) shows the code letter for your
engine. SeeVehicle Identi cation Number (VIN) on
page 5-87. Follow the proper steps to start the engine.
To start a diesel engine, seeStarting the Diesel Engine
on page 2-14.
2-12
Automatic Transmission
Set the parking brake and move your shift lever to
NEUTRAL (N) or PARK (P), if so equipped. Your engine
will not start in any other position — that is a safety
feature.
Manual Transmission
Set the parking brake, shift to neutral NEUTRAL (N)
and hold the clutch pedal to the floor while starting
the engine.
Starter Motor Operation
•The starter motor will disengage if you release
the key or the engine reaches a predetermined
engine speed.
•To prevent overheating, the starter motor will
disengage after continuously operating for
15 seconds. You must release the key from the
start position to re-engage the starter.
•The starter motor will not engage if the engine
is already running.
•The starter motor will disengage if, after
two seconds, the starter pinion gear does not
engage the flywheel or there is no engine
rpm signal from the engine speed sensor.
Starting Your Engine
1. Without pushing the accelerator pedal, turn your
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm.
2. If the engine does not start in 10 seconds, push the
accelerator pedal all the way down and crank the
engine for five more seconds, unless it starts sooner.
3. If your engine still will not start, or starts but then
stops, it could be flooded with too much gasoline.
Wait 15 seconds to let the starter motor cool down.
Do Steps 1 through 3 again.
When the engine starts, let go of the key and the
accelerator pedal.
Notice:Your engine is designed to work with the
electronics in your vehicle. If you add electrical
parts or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer. If you do not, your engine
might not perform properly. Any resulting damage
would not be covered by your vehicle’s warranty.
If you ever need to have your vehicle towed,
seeTowing Your Vehicle on page 4-35.
2-13
If you are trying to start your engine after you have run
out of fuel, seeRunning Out of Fuel on page 5-15.
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 DURAMAX®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.
The following tips will help you get good starting in
cold weather.
•Use the recommended engine oil when the outside
temperature drops below freezing. SeeEngine Oil
(Caterpillar
®Diesel Engine) on page 5-22or
Engine Oil (DURAMAX®Diesel) on page 5-22or
Engine Oil (Gasoline Engine) on page 5-26.
When the outside temperature drops below
0°F (−18°C), use of the optional engine coolant
block heater is recommended.
•If you experience longer cranking times, notice an
unusual amount of exhaust smoke or are at
higher altitudes (over 7,000 ft. or 2 135 m), you may
use your optional engine coolant block heater.
SeeEngine Coolant Heater on page 2-24.
•SeeWhat Fuel to Use on page 5-8for information
on what fuel to use in cold weather.
2-16
During this warm-up period, check your warning lights
and gages:
•If oil pressure does not begin to rise within
15 seconds of starting, stop the engine and find the
cause. SeeOil Pressure Gage on page 3-37for
more information.
•If the engine coolant temperature gage needle goes
into the hot area on the gage, stop the engine and
find the cause of the overheating. SeeEngine
Coolant Temperature Gage on page 3-35for
more information.
•If you have air brakes, the dual-needle air pressure
gage should read at least 115 psi (790 kPa) for
both service systems before you try to move
the vehicle. When air pressure is below 60 psi
(420 kPa), the LOW AIR light will come on and you
will hear a tone alarm. SeeBrake System Warning
Light on page 3-31for more information. If the
pressure does not build up or drops during warm-up,
stop the engine and find the cause before you try
to move the vehicle. Recommended air pressure
before driving is 120 psi (830 kPa). SeeAir
Pressure Gage on page 3-44for more information.
•The charging system light should come on when
the ignition key is turned to RUN or START and
should go out when the engine is running above
idle. If the light does not go out or comes back on
during normal engine operation, have the charging
system checked right away. (This light tells you
if the generator is not charging; it does not reflect
the condition of the battery.) SeeCharging System
Light on page 3-30for more information.
•The voltmeter charge indicator gage tells you the
condition of your battery’s charge. The gage
should be in the center area during engine
operation. The red area on the left indicates an
undercharge condition; the red area on the
right indicates an overcharge. If the gage is in
either red area, have the battery and charging
system checked right away. SeeVoltmeter Gage
on page 3-30for more information.
Notice:Do not allow the engine to operate at low
idle for more than ve minutes. This can cause
low engine operating temperatures which can
affect engine operation and reduce engine life.
Engine idle speed should be increased to 1200 rpm
whenever extended idle is required. Once started,
the engine should be placed under load to allow the
engine coolant temperature to reach 150°F (66°C)
before shutting off the engine.
2-23
Engine Coolant Heater
Your vehicle may be equipped with this feature.
In very cold weather, 0°F (–18°C) or colder, the engine
coolant heater can help. You will get easier starting
and better fuel economy during engine warm-up.
Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your vehicle.
At temperatures above 32°F (0°C), use of the coolant
heater is not required.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Find the plug-in outlet located under the
driver’s door.
3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could
be damaged.
How long should you keep the coolant heater
plugged in? The answer depends on the outside
temperature, the kind of oil you have, and some other
things. Instead of trying to list everything here, we
ask that you contact your dealer in the area where you
will be parking your vehicle. The dealer can give
you the best advice for that particular area.
2-24
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 5-38. 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
®Engines) on page 5-36
orEngine Coolant (Caterpillar®Diesel Engines) on
page 5-38and 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 ShutdownunderStarting the Diesel Engine
on page 2-14. United States
Canada
3-35
If Your Vehicle is Stuck in Sand,
Mud, Ice or Snow
In order to free your vehicle when it is stuck, you will
need to spin the wheels, but you do not want to
spin your wheels too fast. The method known as rocking
can help you get out when you are stuck, but you
must use caution.
{CAUTION:
If you let your tires spin at high speed, they can
explode, and you or others could be injured.
And, the transmission or other parts of the
vehicle can overheat. That could cause an
engine compartment re or other damage.
When you are stuck, spin the wheels as little as
possible. Do not spin the wheels above 35 mph
(55 km/h) as shown on the speedometer.
Notice:Spinning your wheels can destroy parts of
your vehicle as well as the tires. If you spin the
wheels too fast while shifting your transmission
back and forth, you can destroy your transmission.
Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right. That will clear
the area around the front wheels. If you have a
four-wheel-drive vehicle, shift into 4HI. SeeFour-Wheel
Drive on page 2-33. If your vehicle has traction
control, you should turn the traction control system off.
SeeTraction Control System (TCS) on page 4-10.
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 4-35.
4-30
Service............................................................5-3
Doing Your Own Service Work.........................5-4
Two Safety Cautions about Engine Fan
Breakage...................................................5-5
Fuel................................................................5-6
Gasoline Octane............................................5-6
Gasoline Specifications....................................5-6
Additives.......................................................5-6
Diesel Engine Fuel.........................................5-7
What Fuel to Use...........................................5-8
Very Cold Weather Operation.........................5-10
Water in Fuel...............................................5-10
Running Out of Fuel.....................................5-15
Fuel Filter Replacement.................................5-16
Fuels in Foreign Countries.............................5-17
Filling the Tank............................................5-18
Filling a Portable Fuel Container.....................5-19
Checking Things Under the Hood....................5-20
Hood Latches...............................................5-20
Engine Oil (Caterpillar
®Diesel Engine).............5-22
Engine Oil (DURAMAX®Diesel)......................5-22
Engine Oil (Gasoline Engine)..........................5-26
Engine Oil Life System (Gasoline Engine)........5-29
Engine Oil Life System (DURAMAX
®Diesel).....5-31
Engine Oil Life System (Caterpillar®
Diesel Engine)..........................................5-32Engine Air Cleaner/Filter................................5-33
Automatic Transmission Fluid.........................5-34
Manual Transmission Fluid.............................5-35
Engine Coolant (Gas and
DURAMAX
®Engines).................................5-36
Engine Coolant (Caterpillar®Diesel Engines).....5-38
Coolant Surge Tank Pressure Cap..................5-38
Engine Overheating.......................................5-38
Cooling System (Gas and
DURAMAX
®Engines).................................5-40
Engine Fan Noise.........................................5-45
Power Steering Fluid.....................................5-45
Windshield Washer Fluid................................5-46
Brakes........................................................5-47
Battery........................................................5-55
Jump Starting...............................................5-56
Rear Axle.......................................................5-60
Rear Axle Shift Motor....................................5-62
Four-Wheel Drive............................................5-62
Front Axle......................................................5-63
Noise Control System.....................................5-64
Tampering with Noise Control System
Prohibited.................................................5-64
Bulb Replacement..........................................5-65
Windshield Wiper Blade Replacement..............5-65
Section 5 Service and Appearance Care
5-1