2008 HUMMER H3 wheel

Starting and Operating
Your Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an elaborate
break-in. But it will perform better in the long run if
you follow these guidelines:
Keep your speed at 55 mph (88 km/h) or less for
the rst 500 miles (805 km).
Do not drive at any one constant speed, fast or
slow, for the rst 500 miles (805 km). Do not
make full-throttle starts. Avoid downshifting to
brake or slow the vehicle.
Avoid making hard stops for the rst 200 miles
(322 km) or so. During this time the new brake
linings are not yet broken in. Hard stops
with new linings can mean premature wear and
earlier replacement. Follow this breaking-in
guideline every time you get new brake linings.
Do not tow a trailer during break-in. SeeTowing
a Trailer on page 4-50for the trailer towing
capabilities of your vehicle and more
information.
Following break-in, engine speed and load can be
gradually increased.
Ignition Positions
With the key in the ignition
switch, you can turn to
four different positions.
To shift out of PARK (P), the ignition must be in
ON/RUN and the regular brake pedal must be applied.
Notice:Using a tool to force the key from the
ignition switch could cause damage or break the key.
Use the correct key and turn the key only with your
hand. Make sure the key is all the way in. If none of
this works, then your vehicle needs service.
(A) LOCK/OFF:This position locks the ignition. It also
locks the transmission on automatic transmission
vehicles. It locks the steering wheel on manual
transmission vehicles when the key is removed. It is a
theft-deterrent feature. You will only be able to remove
your key when the ignition is turned to LOCK/OFF.
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If you have an automatic transmission, the ignition
switch cannot be turned to LOCK/OFF unless the shift
lever is in PARK (P).
If the steering wheel is locked, move it from right to
left and turn the key to ACC/ACCESSORY. If none of
this works, then your vehicle needs service.
(B) ACC/ACCESSORY:This is the position in which
you can operate your electrical accessories or items
plugged into the accessory power outlets. On automatic
transmission vehicles, this position unlocks the
ignition. On manual transmission vehicles, it unlocks the
ignition and steering wheel. Use this position if your
vehicle must be pushed or towed.
(C) ON/RUN:This is the position that the switch returns
to after you start your engine and release the switch.
The switch stays in ON when the engine is running.
But even when the engine is not running, you can use
ON/RUN to operate the electrical accessories and
to display some instrument panel cluster warning and
indicator lights. The transmission is also unlocked in
this position on automatic transmission vehicles.
The battery could be drained if you leave the key in
the ACC/ACCESSORY or ON/RUN position with
the engine off. You may not be able to start your
vehicle if the battery is allowed to drain for an
extended period of time.START (D):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
When the engine is not running, ACC/ACCESSORY
and ON/RUN allows you to operate the electrical
accessories, such as the radio or items plugged into
the accessory power outlets.
A warning tone will sound if you open the driver’s
door when the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.
Key In the Ignition
Never leave your vehicle with the keys inside, as it is an
easy target for joy riders or thieves. If you leave the
key in the ignition and park your vehicle, a chime
will sound, when you open the driver’s door. Always
remember to remove your key from the ignition and take
it with you. This will lock your ignition and transmission.
Also, always remember to lock the doors.
The battery could be drained if you leave the key in the
ignition while your vehicle is parked. You may not be
able to start your vehicle after it has been parked for an
extended period of time.
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Automatic Transmission Operation
The automatic transmission has a shift lever on the
console.
It features an electronic shift position indicator within
the instrument cluster. This display must be powered
anytime the shift lever is capable of being moved out of
PARK (P). This means that if your key is turned off,
but not in LOCK, there will be a small current drain on
your battery which could discharge your battery over
a period of time. If you need to leave your key in
the ignition but not in LOCK for an extended period,
it is recommended that you disconnect the battery cable
from the battery to prevent discharging your battery.
There are several different positions for your shift lever.PARK (P):This position locks your rear wheels. It is
the best position to use when you start the engine
because your vehicle cannot move easily.
{CAUTION:
It is dangerous to get out of your vehicle if
the shift lever is not fully in PARK (P) with the
parking brake rmly set. Your vehicle can roll.
Do not leave your vehicle when the engine is
running unless you have to. If you have left the
engine running, the vehicle can move suddenly.
You or others could be injured. To be sure your
vehicle will not move, even when you are on
fairly level ground, always set your parking
brake and move the shift lever to PARK (P).
SeeShifting Into PARK (P) (Automatic
Transmission) on page 2-33. If you are pulling a
trailer, seeTowing a Trailer on page 4-50.
Make sure the shift lever is fully in PARK (P)
before starting the engine. Your vehicle has an
automatic transmission shift lock control system.
You must fully apply your regular brakes rst and
then press the shift lever button before you can
shift from PARK (P) when the ignition key is in ON.
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If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way
into PARK (P) as you maintain brake application. Then
press the shift lever button and move the shift lever
into another gear. SeeShifting Out of PARK (P)
(Automatic Transmission) on page 2-35
REVERSE (R):Use this gear to back up.
Notice:Shifting to REVERSE (R) while your vehicle
is moving forward could damage the transmission.
The repairs would not be covered by your warranty.
Shift to REVERSE (R) only after your vehicle is
stopped.
To rock your vehicle back and forth to get out of snow,
ice, or sand without damaging your transmission,
seeIf Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 4-39
NEUTRAL (N):In this position, your engine does not
connect with the wheels. To restart when you are
already moving, use NEUTRAL (N) only.
{CAUTION:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless
your foot is rmly on the brake pedal, your
vehicle could move very rapidly. You could
lose control and hit people or objects. Do not
shift into a drive gear while your engine is
running at high speed.
Notice:Shifting out of PARK (P) or NEUTRAL (N)
with the engine running at high speed may damage
the transmission. The repairs would not be covered
by your warranty. Be sure the engine is not running
at high speed when shifting your vehicle.
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Up-Shift Light
This light will show you
when to shift to the next
higher gear for best
fuel economy.
When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions permit.
For the best fuel economy, accelerate slowly and shift
when the light comes on.
While you accelerate, it is normal for the light to go
on and off if you quickly change the position of
the accelerator. Ignore the shift light when you
downshift.
If your vehicle has four-wheel drive and has a manual
transmission, disregard the shift light when the transfer
case is in four-wheel low.
For more information, seeUp-Shift Light on page 3-32.
Shift Speeds
{CAUTION:
If you skip a gear when you downshift, you
could lose control of your vehicle. You could
injure yourself or others. Do not shift down
more than one gear at a time when you
downshift.
Full-Time Four-Wheel Drive
Full-Time Four-Wheel Drive sends your engine’s driving
power to all four wheels for extra traction. To get the
most out of Full-Time Four-Wheel Drive, you must
be familiar with its operation.
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Transfer Case Buttons
The transfer case buttons are located to the right of the
instrument panel cluster. Use these switches to shift
into and out of the different Full-Time Four-Wheel
Drive modes.
You can choose between four modes:
4
m(Four-Wheel High):This setting is used for driving
in most street and highway situations. You can also
use this setting for light or variable off-road conditions.
N (NEUTRAL):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-48orTowing
Your Vehicle on page 4-48for more information.Notice:Driving on pavement in Four-Wheel
High Lock or Four Wheel Low Lock for extended
periods may cause premature wear on your vehicle’s
powertrain and tires. Do not drive in Four-Wheel
High Lock or Four-Wheel Low Lock on pavement for
extended periods.
4
mQ(Four-Wheel-High Lock):Use this mode
when you need extra traction in most off-road situations
such as sand, mud, snow or level, rocky trails.
Notice:Operating your vehicle in
Four-Wheel-Low Lock above 30 mph (48 km/h) for
any extended period of time could cause damage
to the transfer case. Do not operate your vehicle
in Four-Wheel-Low Lock above 30 mph (48 km/h) for
extended periods.
4
nQ(Four-Wheel-Low Lock):This mode delivers
extra torque to all four wheels and is used for extreme
off-road conditions. You might choose 4-Wheel-Low
Lock if you are driving in off-road situations, such as,
deep sand, mud, or snow and climbing or descending
steep hills.
If the vehicle has a locking rear axle, when in this mode
you can also choose to lock the rear axle for additional
traction in extreme off-road situations. SeeLocking Rear
Axle on page 4-6.
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Indicator lights in the buttons show which mode you
are in. The indicator lights will come on briey when
you turn on the ignition the mode the vehicle is in
will stay on. If the lights do not come on, you should
take your vehicle to your dealer for service. An indicator
light will ash while shifting the transfer case. It will
remain lit when the shift is complete. If for some reason
the transfer case cannot make a requested shift,
it will return to the last chosen setting.
If the SERV 4WD message on the Driver Information
Center (DIC) stays on, you should take your vehicle to
your dealer for service. See Service 4WD message
underDIC Warnings and Messages on page 3-43.
Shifting between Four-Wheel High
and Four-Wheel-High Lock
With the vehicle traveling less than 45 mph
(72 km/h), press and release the Four-Wheel High
or Four-Wheel-High Lock button. The indicator light
will ash while shifting. It will remain lit when the
shift is complete.
It may be necessary to drive backwards while turning
for a distance of 25 feet (7.5 m) to get the lock
feature to disengage.
Shifting into Four-Wheel Low Lock
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
To shift into Four-Wheel-Low Lock, the ignition must be in
ON and the vehicle must be stopped or moving less than
3 mph (5 km/h) with the transmission in NEUTRAL (N).
The preferred method for shifting into Four-Wheel Low is
to have your vehicle moving 1 to 2 mph (1.6 to 3.2 km/h).
Press and release the Four-Wheel-Low Lock button.
If your vehicle has a manual transmission, the clutch
pedal must be pressed to the oor while you press the
Four-Wheel-Low Lock button, or the shift will not be
completed. You must wait for the Four-Wheel-Low Lock
indicator light to stop ashing and remain lit before
shifting your transmission in gear.
It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High ranges or from NEUTRAL with
the engine running.
If the Four-Wheel-Low Lock button is pressed when
your vehicle is in gear and/or moving too fast, the
Four-Wheel-Low Lock indicator light will ash for
15 seconds and not complete the shift unless your
vehicle is moving less than 3 mph (5 km/h) and
the transmission is in NEUTRAL (N). After 15 seconds
the transfer case will return to the last chosen setting.
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Shifting Out of Four-Wheel-Low Lock
Notice:Shifting the transmission into gear before
the indicator light stops ashing could cause
damage to the transfer case. Always wait until the
indicator light stops ashing before putting the
transmission back in gear.
To shift out of Four-Wheel-Low Lock, your vehicle must
be stopped or moving less than 3 mph (5 km/h) with the
transmission in NEUTRAL (N) and the ignition in ON. The
preferred method for shifting out of Four-Wheel-Low
Lock is to have your vehicle moving 1 to 2 mph
(1.6 to 3.2 km/h). Press and release the Four-Wheel High
or Four-Wheel-High Lock button. If your vehicle has a
manual transmission, the clutch pedal must be pressed
to the oor while you press the Four-Wheel High or
Four-Wheel-High Lock button, or the shift will not be
completed. You must wait for the Four-Wheel High or
Four-Wheel-High Lock indicator light to stop ashing and
remain lit before shifting your transmission into gear.It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High ranges or from NEUTRAL with
the engine running.
If the Four-Wheel High or Four-Wheel-High Lock button
is pressed when your vehicle is in gear and/or moving
too fast, the Four-Wheel High or Four-Wheel-High Lock
indicator light will ash for 15 seconds but will not
complete the shift unless your vehicle is moving less than
3 mph (5 km/h) and the transmission is in NEUTRAL (N).
Shifting Into NEUTRAL
To shift the transfer case to NEUTRAL, do the following:
1. Set the parking brake.
2. Start the vehicle by turning the ignition to START.
3. Put the transmission in NEUTRAL (N). If your
vehicle has a manual transmission, press and
hold the clutch pedal down while you perform
Steps 5 through 9.
4. Shift the transfer case to Four-Wheel High.
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