engine HUMMER H2 2008 User Guide

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 it is, turn the steering wheel left and right while
you turn the key hard. If none of this works,
then your vehicle needs service.
B (ACC/ACCESSORY):This position lets things like
the radio and the windshield wipers operate while
the engine is off.
Lengthy operation of features such as the radio in the
ACC/ACCESSORY ignition position and the ON/RUN
position may drain the battery and prevent your vehicle
from starting. Do not operate your vehicle in the
ACC/ACCESSORY ignition position for a long period
of time.
C (ON/RUN):This is the position for driving. It is the
position the ignition switch returns to after the engine
starts, and the key is released.
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.
D (START):This position starts the engine.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.
Retained Accessory Power (RAP)
These vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Sunroof
Power Windows
The sunroof and power windows will continue to work
up to 10 minutes after the key is turned to LOCK/OFF or
until any door is opened. The radio will continue to
work for up to 10 minutes after the key is turned
to LOCK/OFF or until the driver’s door is opened.
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Starting the Engine
Move your shift lever to PARK (P) or NEUTRAL (N).
Your engine will not start in any other position – this is
a safety feature. To restart when you are already
moving, use NEUTRAL (N) only.
Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could damage the
transmission. Shift to PARK (P) only when your
vehicle is stopped.
Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm. Do not race the engine
immediately after starting it. Operate the engine and
transmission gently to allow the oil to warm up and
lubricate all moving parts.
Your vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the engine
and protects components. If the ignition key is turned
to the START position, and then released when the
engine begins cranking, the engine will continue
cranking for a few seconds or until the vehicle starts.
If the engine does not start and the key is held in
START for many seconds, cranking will be stopped
after 15 seconds to prevent cranking motor damage.To prevent gear damage, this system also prevents
cranking if the engine is already running. Engine
cranking can be stopped by turning the ignition
switch to the ACC/ACCESSORY or LOCK/OFF
position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down.
2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F or−18°C),
it could be ooded with too much gasoline. Try
pushing the accelerator pedal all the way to the oor
and holding it there as you hold the key in START
for up to a maximum of 15 seconds. Wait at least
15 seconds between each try, to allow the cranking
motor to cool down. When the engine starts, let go of
the key and accelerator. If the vehicle starts briey
but then stops again, do the same thing. This clears
the extra gasoline from the engine. Do not race the
engine immediately after starting it. Operate the
engine and transmission gently until the oil warms up
and lubricates all moving parts.
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Notice:The 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/retailer. If you do not, your
engine might not perform properly. Any resulting
damage would not be covered by your vehicle’s
warranty.
Engine Coolant Heater
The engine coolant heater, if available, can help in cold
weather conditions at or below 0°F (−18°C) for easier
starting and better fuel economy during engine warm-up.
Plug in the coolant heater at least four hours before
starting your vehicle. An internal thermostat in the
plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above 0°F (−18°C).
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Locate the electrical cord near the front recovery
loop on the driver’s side of the vehicle.
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/retailer in the area where you will be
parking your vehicle. The dealer/retailer can give you
the best advice for that particular area.
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Automatic Transmission Operation
Your vehicle has a Hydra-Matic®6L80 automatic
transmission, and has an electronic shift position
indicator within the instrument panel cluster. This display
comes on when the ignition key is turned to the
ON/RUN position.
There are several different positions for the shift lever.
PARK (P):This position locks the rear wheels. It is the
best position to use when you start your engine
because your vehicle cannot move easily.
When parked on a hill, especially when the vehicle
has a heavy load, you may notice an increase in the
effort to shift out of PARK (P). See Torque Lock
(Automatic Transmission) underShifting Into PARK (P)
on page 2-41for more information.{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) on
page 2-41. If you are pulling a trailer, see
Towing a Trailer on page 4-55.
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.
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To rock your vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission, see
If Your Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 4-39.
NEUTRAL (N):In this position, the engine does not
connect with the wheels. To restart when you are
already moving, use NEUTRAL (N) only. Also, use
NEUTRAL (N) when your vehicle is being towed.
{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.DRIVE (D):This position is for normal driving. It
provides the best fuel economy for your vehicle. If you
need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
By doing this, the vehicle shifts down to the next gear
and has more power.
DRIVE (D) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road
driving. You may want to shift the transmission to a
lower gear selection if the transmission shifts too often.
Downshifting the transmission in slippery road
conditions could result in skidding, see Skidding under
Loss of Control on page 4-12.
MANUAL MODE (M):This position lets drivers select
the range of gears appropriate for current driving
conditions. If your vehicle has this feature, see Driver
Shift Control (DSC) later in this section.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator pedal
may damage the transmission. The repair will not be
covered by your warranty. If you are stuck, do not
spin the tires. When stopping on a hill, use the brakes
to hold the vehicle in place.
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SECOND (2):This position reduces vehicle speed
without using the brakes. Use SECOND (2) on hills.
It can help control your speed as you go down steep
mountain roads, but then you may also want to use the
brakes off and on.
FIRST (1):This position reduces vehicle speed without
using the brakes. Use it for major/severe downgrades
and off-road driving where the vehicle would otherwise
accelerate due to steepness of grade.
When you shift to SECOND (2) or FIRST (1) it provides
the lowest gear appropriate to your current road
speed and continues to downshift as the vehicle slows,
eventually downshifting to the selected gear.
Your vehicle has a shift stabilization feature that
adjusts the transmission shifting to the current driving
conditions in order to reduce rapid upshifts and
downshifts. This shift stabilization feature is designed to
determine, before making an upshift, if the engine
will be able to maintain vehicle speed by analyzing
things such as vehicle speed, throttle position andvehicle load. If the shift stabilization feature determines
that a current vehicle speed cannot be maintained,
the transmission does not upshift and instead holds the
current gear. In some cases, this may appear to be
a delayed shift, however the transmission is operating
normally.
Your vehicle’s transmission uses adaptive shift controls
that compares key shift parameters to pre-programmed
ideal shifts stored in the transmissions computer.
The transmission constantly makes adjustments to
improve vehicle performance according to how
the vehicle is being used, such as with a heavy load or
when temperature changes. During this adaptive
shift controls process, shifting may feel different as the
transmission determines the best settings.
When temperatures are very cold, the Hydra-Matic
®
6L80 automatic transmission’s gear shifting may
be delayed providing more stable shifts until the engine
warms up. Shifts may be more noticeable with a cold
transmission. This difference in shifting is normal.
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Tow/Haul Mode
Your vehicle is equipped
with a tow/haul mode.
The button is located on
the instrument panel
to the right of the
steering wheel.
You can use this feature to assist when towing or
hauling a heavy load. See “Tow/Haul Mode” under
Towing a Trailer on page 4-55for more information.
Full-Time Four-Wheel Drive
The transfer case on your Full-Time Four-Wheel Drive
vehicle is designed to constantly send the 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.
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.
Transfer Case Dial
The transfer case dial is
located to the right of the
instrument panel cluster.
Use this switch to shift into
and out of the different
Full-Time Four-Wheel
Drive modes.
The transfer case is a part of the Full-Time Four-Wheel
Drive system and allows the following four different
modes of operation:
4
m(Full-Time Four-Wheel Drive):This setting is used
for driving in most street and highway situations.
It can be used for light or variable off-road conditions.
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.
4
nQ(Four-Wheel-Low Lock):This mode delivers
extra torque to all four wheels and is used for extreme
off-road conditions. Choose Four-Wheel-Low Lock while
driving off-road in deep sand, mud, or snow and climbing
or descending steep hills.
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Shifting between Four-Wheel High and
Four-Wheel-High Lock
With the vehicle traveling less than 40 mph
(64 km/h), turn the dial to the Four-Wheel High or
Four-Wheel-High Lock position. The indicator light on
the dial will ash while shifting. It will remain on
when the shift is complete.
It may be necessary to drive backwards for a short
distance of 25 feet (7.5 m) to get the lock feature
to disengage.
Shifting into Four-Wheel-Low Lock
To shift into Four-Wheel-Low Lock, the ignition must be
in RUN 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). Turn the dial to the
Four-Wheel-Low Lock position. You must wait for the
Four-Wheel-Low Lock indicator light on the dial to
stop ashing and remain lit before shifting the
transmission in gear.When the transfer case is shifted into Four-Wheel-Low
Lock position a StabiliTrak
®indicator light will come
on to show that the system has been turned off and a
message will show in the DIC. SeeDIC Warnings
and Messages on page 3-56for more information.
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.
It is normal for your vehicle to have engagement noise
and bump when shifting between Four-Wheel Low
and Four-Wheel High or Four-Wheel-High Lock ranges
or from NEUTRAL with the engine running.
If the Four-Wheel-Low Lock position is selected when
your vehicle is in gear and/or moving, 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 setting last chosen.
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Shifting Out of Four-Wheel Low Lock
To shift from Four-Wheel-Low Lock to Four-Wheel High
or Four-Wheel-High 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 RUN. 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). Turn the dial to the
Four-Wheel High or Four-Wheel-High Lock position.
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 or Four-Wheel-High Lock ranges
or from NEUTRAL with the engine running.
If the Four-Wheel High or Four-Wheel-High Lock position
is selected when your vehicle is in gear and/or moving,
the Four-Wheel High or Four-Wheel-High Lock indicator
light will ash for 30 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).
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.
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it will not roll.
2. Set the parking brake and apply the regular brake
pedal. SeeParking Brake on page 2-40
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to NEUTRAL
position. The transfer case will not shift to NEUTRAL
unless this position is held for 10 seconds.
The NEUTRAL light will come on and then the dial
can be slowly released. The dial will be in the
Four-Wheel Low Lock position but the transfer case
will be in NEUTRAL with the NEUTRAL light on.
7. If the engine is running, make sure that the transfer
case is in NEUTRAL (N) by shifting the transmission
to REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
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Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular brake
pedal.
2. Shift the transmission to NEUTRAL (N) and turn
the ignition to RUN with the engine off.
3. Turn the transfer case dial to Four-Wheel High,
Four-Wheel High Lock or Four-Wheel Low Lock.
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the requested mode indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
mode indicator lights to stop ashing before shifting
the transmission into gear.
5. Start the engine and shift the transmission to the
desired position.
Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime will activate and
the warning light will ash
when the parking brake
is applied and the vehicle
is moving at least 3 mph
(5 km/h) for at least
three seconds.
To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever, located
above the parking brake pedal, with the parking
brake symbol, to release the parking brake.
If the ignition is on when the parking brake is released,
the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-55.
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