2008 HUMMER H2 wheel

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:
{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.
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.
When driving across an incline that is not too steep, the
vehicle can hit some loose gravel and start to slide
downhill. 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.
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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.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.
4-30

Driving in Water
{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.
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 (50 cm). 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.
SeeDriving in Rain and on Wet Roads on page 4-33
for more information on driving through water.
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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
If your vehicle has 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.
Driving at Night
Night driving is more dangerous than day driving because
some drivers are likely to be impaired — by alcohol or
drugs, with night vision problems, or by fatigue.
Night riving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by adjusting the inside
rearview mirror.
Slow down and keep more space between you and
other vehicles because your headlamps can only
light up so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into approaching headlamps.
Keep the windshield and all glass on your vehicle
clean — inside and out.
Keep your eyes moving, especially during turns
or curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
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Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine
again and repeat this only when you feel really
uncomfortable from the cold. But do it as little as
possible. Preserve the fuel as long as you can.
To help keep warm, you can get out of the vehicle
and do some fairly vigorous exercises every half hour
or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free your
vehicle when stuck in sand, mud, ice, or snow.
SeeRocking Your Vehicle to Get It Out on page 4-40.
If your vehicle has a traction system, it can often help to
free a stuck vehicle. Refer to your vehicle’s traction
system in the Index. If the stuck condition is too severe
for the traction system to free the vehicle, turn the
traction system off and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. The vehicle can overheat,
causing an engine compartment re or other
damage. Spin the wheels as little as possible
and avoid going above 35 mph (55 km/h) as
shown on the speedometer.
For information about using tire chains on your vehicle,
seeTire Chains on page 5-75.
4-39

Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right to clear
the area around the front wheels. The traction control
system activates when the system senses that the
wheels are spinning. SeeTraction Control System (TCS)
on page 4-5. Then, shift back and forth between
REVERSE (R) and a forward gear, spinning the wheels
as little as possible. To prevent transmission wear,
wait until the wheels stop spinning before shifting gears.
Release the accelerator pedal while you shift, and
press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning the wheels in
the forward and reverse directions, you will cause a
rocking motion that could free your vehicle. If that does
not get your vehicle out after a few tries, it might
need to be towed out. Or, you can use the recovery
loops. If your vehicle does need to be towed out,
seeTowing Your Vehicle on page 4-51.
Recovery Loops
{CAUTION:
These loops, when used, are under a lot of
force. Keep people away from the vicinity of
the loops and any chains or cables during use.
Always pull the vehicle straight out. Never pull
on the loops at a sideways angle. The loops
could break off and you or others could be
injured from the chain or cable snapping back.
Notice:Never use the recovery loops to tow the
vehicle. Your vehicle could be damaged and it would
not be covered by warranty.
4-40

Front Mounted Receiver
Your vehicle is equipped with a front mounted receiver.
You can use the receiver with a power winch platform
(described later in this section) or with other
accessories.
Never use the front mounted receiver to tow a trailer.
You can use the front mounted receiver to tow your
vehicle behind another. SeeRecreational Vehicle
Towing on page 4-51.
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.
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Towing
Towing Your Vehicle
Consult your dealer/retailer or a professional towing
service if you need to have your disabled vehicle towed.
SeeRoadside Assistance Program on page 7-6.
If you want to tow your vehicle behind another vehicle
for recreational purposes (such as behind a motorhome),
see “Recreational Vehicle Towing” following.
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 4-34.
4-51