wheel HUMMER H2 2006 Workshop Manual

Q:Are there some things I should not do when
driving down a hill?
A:Yes! These are important because if you ignore
them you could lose control and have a serious
accident:
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down may be too steep to drive
across. You could roll over if you do not drive
straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work and
could overheat and fade.
Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill. But if
it happens going downhill, here is what to do:
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) and, while still braking, restart
the engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
4-30

Driving Across an Incline
Sooner or later, an off-road trail will probably go across
the incline of a hill. If this happens, you have to
decide whether to try to drive across the incline. Here
are some things to consider:
A hill that can be driven straight up or down may
be too steep to drive across. When you go
straight up or down a hill, the length of the wheel
base — the distance from the front wheels to
the rear wheels — reduces the likelihood the vehicle
will tumble end over end. But when you drive
across an incline, the much more narrow track
width — the distance between the left and
right wheels — may not prevent the vehicle from
tilting and rolling over. Also, driving across an incline
puts more weight on the downhill wheels. This
could cause a downhill slide or a rollover.
Surface conditions can be a problem when you
drive across a hill. Loose gravel, muddy spots,
or even wet grass can cause your tires to slip
sideways, downhill. If the vehicle slips sideways, it
can hit something that will trip it — a rock, a
rut, etc. — and roll over.
Hidden obstacles can make the steepness of the
incline even worse. If you drive across a rock with the
uphill wheels, or if the downhill wheels drop into a rut
or depression, your vehicle can tilt even more.For reasons like these, you need to decide carefully
whether to try to drive across an incline. Just because the
trail goes across the incline does not mean you have to
drive it. The last vehicle to try it might have rolled over.
{CAUTION:
Driving across an incline that is too steep will
make your vehicle roll over. You could be
seriously injured or killed. If you have any
doubt about the steepness of the incline, do
not drive across it. Find another route instead.
Q:What if I am driving across an incline that is not
too steep, but I hit some loose gravel and start
to slide downhill. What should I do?
A:If you feel your vehicle starting to slide sideways,
turn downhill. This should help straighten out the
vehicle and prevent the side slipping. However,
a much better way to prevent this is to get out and
“walk the course” so you know what the surface
is like before you drive it.
4-31

Stalling on an Incline
If your vehicle stalls when you are crossing an incline,
be sure you, and any passengers, get out on the
uphill side, even if the door there is harder to open. If
you get out on the downhill side and the vehicle starts to
roll over, you will be right in its path.
If you have to walk down the slope, stay out of the path
the vehicle will take if it does roll over.{CAUTION:
Getting out on the downhill (low) side of a
vehicle stopped across an incline is
dangerous. If the vehicle rolls over, you could
be crushed or killed. Always get out on the
uphill (high) side of the vehicle and stay well
clear of the rollover path.
Driving in Mud, Sand, Snow, or Ice
When you drive in mud, snow, or sand, your wheels will
not get good traction. You cannot accelerate as quickly,
turning is more difficult, and you will need longer braking
distances.
It is best to use a low gear when you are in mud — the
deeper the mud, the lower the gear. In really deep
mud, the idea is to keep your vehicle moving so you do
not get stuck. Be careful to keep mud from building
up and washing onto the engine cooling system.
When you drive on sand, you will sense a change in
wheel traction. But it will depend upon how loosely
packed the sand is. On loosely packed sand, such as
on beaches or sand dunes, your tires will tend to
sink into the sand. This has an effect on steering,
accelerating, and braking. Drive at a reduced speed and
avoid sharp turns or abrupt maneuvers.
4-32

Hard packed snow and ice offer the worst tire traction.
On these surfaces, it is very easy to lose control.
On wet ice, for example, the traction is so poor that you
will have difficulty accelerating. And if you do get
moving, poor steering and difficult braking can cause
you to slide out of control.
{CAUTION:
Driving on frozen lakes, ponds, or rivers can
be dangerous. Underwater springs, currents
under the ice, or sudden thaws can weaken the
ice. Your vehicle could fall through the ice and
you and your passengers could drown. Drive
your vehicle on safe surfaces only.
Driving in Water
Heavy rain can mean ash ooding, and ood waters
demand extreme caution.
Find out how deep the water is before you drive through
it. If it is deep enough to cover your wheel hubs, axles, or
exhaust pipe, do not try it — you probably will not get
through. Also, water that deep can damage your axle and
other vehicle parts. Your vehicle is capable of depths up
to 20 inches. Know how to judge whether the water is
deeper than this before proceeding into it.If the water is not too deep, drive slowly through it. At
faster speeds, water splashes on your ignition
system and your vehicle can stall. Stalling can also
occur if you get your tailpipe under water. And, as long
as your tailpipe is under water, you will never be
able to start your engine. When you go through water,
remember that when your brakes get wet, it may
take you longer to stop.
{CAUTION:
Driving through rushing water can be
dangerous. Deep water can sweep your
vehicle downstream and you and your
passengers could drown. If it is only shallow
water, it can still wash away the ground from
under your tires, and you could lose traction
and roll the vehicle over. Do not drive through
rushing water.
SeeDriving in Rain and on Wet Roads on page 4-39for
more information on driving through water.
4-33

After Off-Road Driving
Remove any brush or debris that has collected on the
underbody, chassis, or under the hood. These
accumulations can be a re hazard.
After operation in mud or sand, have the brake linings
cleaned and checked. These substances can cause
glazing and uneven braking. Check the engine and oil
coolers for mud accumulation. Thoroughly and carefully
clean these devices to allow proper cooling. Check
the body structure, steering, suspension, wheels, tires,
and exhaust system for damage. Also, check the
fuel lines and cooling system for any leakage.
Your vehicle will require more frequent service due to
off-road use. See the Maintenance Schedule for
additional information.
Assist Steps
Your vehicle may be equipped with removable side steps.
Remove the steps prior to off-roading to give your
vehicle more ground clearance and to prevent damage
to the vehicle from the side steps dragging and/or
catching on obstacles.
Notice:Do not drive off-road with the side steps
attached to your vehicle. You can damage the side
steps and/or your vehicle’s frame if they get caught
or drag against an obstacle. This damage would not
be covered by your vehicle’s warranty. Always
remove the side steps prior to any off-road driving.
U-Type Side Steps
The following instructions show how to install the
optional U-type steps. If you want to remove them, just
reverse the instructions:
1. Start with the side step brackets pointing up and
away from you, or just make sure the HUMMER
logo faces up.
2. For the front step, use the rst and third brackets
on the vehicle from the front tire. For the rear step,
use the rst and third brackets on the vehicle
from the rear tire.
You will notice that the side steps have pins on
both sides of the step brackets. This is because the
steps are interchangeable between front/back
and the driver/passenger sides of the vehicle. Use
the pins as follows:
Driver Side:Look at the side step with the
HUMMER logo facing you. You will use the pins
which are on the right side of each side step
bracket. This works for the front or rear of
the vehicle.
Passenger Side:Look at the side step with the
HUMMER logo facing you. You will use the pins
which are on the left side of each side step
bracket. This works for the front or rear of
the vehicle.
4-34

Before Leaving on a Long Trip
Make sure you are ready. Try to be well rested. If you
must start when you are not fresh — such as after
a day’s work — do not plan to make too many miles that
rst part of the journey. Wear comfortable clothing
and shoes you can easily drive in.
Is your vehicle ready for a long trip? If you keep it
serviced and maintained, it is ready to go. If it needs
service, have it done before starting out. Of course,
you will nd experienced and able service experts in
GM dealerships all across North America. They will be
ready and willing to help if you need it.
Here are some things you can check before a trip:
Windshield Washer Fluid:Is the reservoir full? Are
all windows clean inside and outside?
Wiper Blades:Are they in good shape?
Fuel, Engine Oil, Other Fluids:Have you checked
all levels?
Lamps:Are they all working? Are the lenses clean?
Tires:They are vitally important to a safe,
trouble-free trip. Is the tread good enough for
long-distance driving? Are the tires all inated to the
recommended pressure?
Weather Forecasts:What is the weather outlook
along your route? Should you delay your trip a
short time to avoid a major storm system?
Maps:Do you have up-to-date maps?
Highway Hypnosis
Is there actually such a condition as highway hypnosis?
Or is it just plain falling asleep at the wheel? Call it
highway hypnosis, lack of awareness, or whatever.
There is something about an easy stretch of road with
the same scenery, along with the hum of the tires on the
road, the drone of the engine, and the rush of the
wind against the vehicle that can make you sleepy. Do
not let it happen to you! If it does, your vehicle can
leave the road in less than a second, and you could
crash and be injured.
What can you do about highway hypnosis? First, be
aware that it can happen.
Then here are some tips:
Make sure your vehicle is well ventilated, with a
comfortably cool interior.
Keep your eyes moving. Scan the road ahead and
to the sides. Check your mirrors and your
instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get some
exercise, or both. For safety, treat drowsiness
on the highway as an emergency.
4-43

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.
For more information about using tire chains on your
vehicle, seeTire Chains on page 5-67.
Rocking Your Vehicle to Get It Out
First, turn your steering wheel left and right. That
will clear the area around your front wheels. Your vehicle
has a traction control system that will activate when
the system senses that the wheels are spinning.
SeeTraction Control System (TCS) on page 4-9for
more information. Then, with the wheels straight ahead,
shift back and forth between REVERSE (R) and a
forward gear, 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.
Or, you can use your recovery loops. If you do need
to be towed out, seeTowing Your Vehicle on page 4-59.
4-50

Power Winch Platform
You can use the power winch platform (if equipped) with
an aftermarket winch. Connect the winch to the
platform and wiring to the vehicle following the winch
manufacturer’s guidelines.
Notice:Do not use the winch platform to winch at
a tension of more than 9,000 lbs. (4 082 kg). This
would damage your vehicle’s frame. This damage
would not be covered by your vehicle’s warranty.
If you are using a winch to pull out another vehicle,
follow the winch manufacturer’s guidelines and observe
the following to prevent damage to your vehicle:
If possible, have your vehicle anchored from
the opposite side of the winch to a solid,
immovable object.
If winching from the front, use both of the rear
recovery loops. If winching from the rear, use both
of the front recovery loops.
Put your transmission in NEUTRAL (N).
Use your regular brakes to hold your vehicle in
place and block the wheels to keep the vehicle
from moving.Notice:Using a power winch with the transmission
in gear to pull out another vehicle may damage
the transmission. When operating a power winch,
always leave the transmission in NEUTRAL (N).
Notice:Driving your vehicle through an automatic
car wash with the winch installed, can cause
damage to your vehicle and the car wash. Always
remove the winch from your vehicle before using an
automatic car wash. SeeWashing Your Vehicle
on page 5-109for more information.
If you are using a winch to pull out your own vehicle,
follow the winch manufacturer’s guidelines for self
recovery and observe the following to prevent damage
to your vehicle:
Do not self recover your vehicle by wrapping the
winch cable around an object (such as a pulley
block or tree) and attaching it back to your vehicle’s
recovery loops.
Always attach the winch cable directly to a solid
anchor directly in front of your vehicle to achieve
a straight line pull.
4-54

Recreational Vehicle Towing
Recreational vehicle towing means towing your vehicle
behind another vehicle – such as behind a motorhome.
The two most common types of recreational vehicle
towing are known as “dinghy towing” (towing your vehicle
with all four wheels on the ground) and “dolly towing”
(towing your vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).
With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing,” following.
Here are some important things to consider before you
do recreational vehicle towing:
What’s the towing capacity of the towing vehicle?
Be sure you read the tow vehicle manufacturer’s
recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they can tow.
Do you have the proper towing equipment?
See your dealer or trailering professional for
additional advice and equipment recommendations.
Is your vehicle ready to be towed? Just as you
would prepare your vehicle for a long trip, you’ll
want to make sure your vehicle is prepared to be
towed. SeeBefore Leaving on a Long Trip on
page 4-43.
Dinghy Towing
Use the following procedure to tow your vehicle:
1. Shift the transmission to PARK (P).
2. Turn the engine off, but leave the ignition in
ACCESSORY.
3. Firmly set the parking brake.
4. Securely attach the vehicle being towed to the
tow vehicle.
{CAUTION:
Shifting a full-time four-wheel-drive vehicle’s
transfer case into NEUTRAL can cause your
vehicle to roll even if the transmission is in
PARK (P). You or others could be injured.
Make sure the parking brake is rmly set
before you shift the transfer case to NEUTRAL.
5. Shift the transfer case to NEUTRAL (N). See
Full-Time Four-Wheel Drive on page 2-30for
the proper procedure to select the NEUTRAL
position for your vehicle.
4-60

6. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle. You can use your vehicle’s front mounted
receiver with the proper accessories to tow it.
See “Front Mounted Receiver” underIf Your Vehicle
is Stuck in Sand, Mud, Ice or Snow on page 4-50.
7. Turn the ignition to ACCESSORY.
8. Disconnect the battery if you are going to tow for
long distances or long periods of time.
When towing your vehicle for extended periods of time,
start your vehicle as often as possible to prevent
battery drain. This should only be done when the tow
vehicle is parked.
Dolly Towing
Your vehicle cannot be dolly towed. If you must tow
your vehicle behind another, use the dinghy towing
procedure listed previously.
Notice:Dolly towing your vehicle will damage
drivetrain components. Do not dolly tow your
vehicle.
Selectable Extended Rear
Ride Height
If your vehicle has this feature it comes as part of the
electronically controlled air suspension system.
The selectable rear ride height allows you to raise the
rear of the vehicle about 2 inches (5 cm) over the normal
ride height. This can be helpful when driving off-road
where you may need more ground clearance to clear an
obstacle.
The button that controls this
feature is located on the
instrument panel to the
right of the steering wheel.
To use this feature, ensure that the following conditions
are met:
The engine must be running.
All doors must be fully closed. The suspension will
not raise or lower if a door is open.
The vehicle speed must be less than 40 mph
(64 km/h). The system will not activate otherwise.
4-61