tires HUMMER H3 2010 User Guide

9-8 Driving and Operating
Loading Your Vehicle for
Off-Road Driving
{WARNING
.Cargo on the load floor piled
higher than the seatbacks
can be thrown forward during
a sudden stop. You or your
passengers could be injured.
Keep cargo below the top of
the seatbacks.
.Unsecured cargo on the load
floor can be tossed about
when driving over rough
terrain. You or your
passengers can be struck
by flying objects. Secure
the cargo properly.(Continued)
WARNING (Continued)
.Heavy loads on the roof raise
the vehicle's center of gravity,
making it more likely to roll
over. You can be seriously or
fatally injured if the vehicle
rolls over. Put heavy loads
inside the cargo area, not on
the roof. Keep cargo in the
cargo area as far forward and
low as possible.
There are some important things to
remember about how to load your
vehicle.
.The heaviest things should be
on the floor, forward of the rear
axle. Put heavier items as far
forward as you can.
.Be sure the load is properly
secured, so things are not
tossed around. You will find other important
information under
Vehicle Load
Limits
on page 9‑27and Tireson
page 10‑44.
Environmental Concerns
Off-road driving can provide
wholesome and satisfying
recreation. However, it also
raises environmental concerns.
We recognize these concerns
and urge every off-roader to follow
these basic rules for protecting the
environment:
.Always use established trails,
roads, and areas that have been
specially set aside for public
off-road recreational driving and
obey all posted regulations.
.Avoid any driving practice
that could damage shrubs,
flowers, trees, or grasses or
disturb wildlife. This includes
wheel-spinning, breaking down
trees, or unnecessary driving
through streams or over soft
ground.

9-14 Driving and Operating
Crossing Obstacles
Approach Angle—a Key to
Mobility
If you encounter a large dip in the
terrain, do not enter straight on;
enter at an angle —15° minimum
approach (A), 75° maximum
approach angle (B). For very large
dips, ditches or small washes, coast
in, using the engine as a brake
(transmission and transfer case
lowest gears). Then, use the low
ranges in the transmission and
transfer case to power out. Roll The Tires Over Large Rocks
Do not straddle large rocks; drive
over them, letting the tire cover the
rock. The tread of the tire is thicker
and tougher than the sidewall of the
tire and is more resilient to impact
than underbody components.
Log Crossing
Using the proper technique,
the vehicle will cross logs up to
25.4 cm (10 inches) in diameter.
Approach the log at approximately a
15° angle (A) with the transmission
in 1 (First) and the transfer case in
Four‐Wheel‐Low Lock and
“walk”the vehicle over, one tire at a time.
It may be necessary to modulate
the brake pedal and accelerator to
avoid spin-out. Ease the vehicle
down from the log with the brake.
Driving on Hills
Off-road driving often takes you up,
down, or across a hill. Driving safely
on hills requires good judgment
and an understanding of what the
vehicle can and cannot do. There
are some hills that simply cannot be
driven, no matter how well built the
vehicle.

Driving and Operating 9-19
Driving Across an Incline
An off-road trail will probably go
across the incline of a hill. To decide
whether to try to drive across the
incline, consider the following:
{WARNING
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 might be too steep
to drive across. When going
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 driving across an incline, the narrower
track width
—the distance
between the left and right
wheels —might not prevent the
vehicle from tilting and rolling
over. Driving across an incline
puts more weight on the downhill
wheels which could cause a
downhill slide or a rollover.
.Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the 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, the vehicle can tilt
even more. For these reasons, carefully
consider 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.
If you feel the vehicle starting to
slide sideways, turn downhill.
This should help straighten out
the vehicle and prevent the side
slipping. The best way to prevent
this is to
“walk the course” first, so
you know what the surface is like
before driving it.

9-20 Driving and Operating
Stalling on an Incline
{WARNING
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.
If the vehicle stalls when 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.
Driving in Mud, Sand, Snow,
or Ice
When you drive in mud, snow,
or sand, the wheels do not get good
traction. Acceleration is not as
quick, turning is more difficult, and
braking distances are longer.
It is best to use a low gear when in
mud —the deeper the mud, the
lower the gear. In really deep mud,
keep the vehicle moving so it does
not get stuck.
When driving on sand, wheel
traction changes. On loosely packed
sand, such as on beaches or sand
dunes, the tires will tend to sink
into the sand. This affects 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 the
vehicle does get moving, poor
steering and difficult braking can
cause it to slide out of control.
{WARNING
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 and Operating 9-21
Driving in Water
{WARNING
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 flash flooding,
and flood waters demand extreme
caution. Find out how deep the water is
before driving through it. Do not
try it if it is deep enough to cover
the wheel hubs, axles, or exhaust
pipe
—you probably will not get
through. Deep water can damage
the axle and other vehicle parts.
The vehicle is capable of depths up
to 50 cm (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 the ignition
system and the vehicle can stall.
Stalling can also occur if you get the
tailpipe under water. If the tailpipe is
under water, you will never be able
to start the engine. When going
through water, remember that when
the brakes get wet, it might take
longer to stop. See Driving on Wet
Roads on page 9‑22.
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 fire 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 and
check the fuel lines and cooling
system for any leakage.
The vehicle requires more frequent
service due to off-road use. Refer
to the Maintenance Schedule for
additional information.

9-22 Driving and Operating
Driving on Wet Roads
Rain and wet roads can reduce
vehicle traction and affect your
ability to stop and accelerate.
Always drive slower in these types
of driving conditions and avoid
driving through large puddles and
deep‐standing or flowing water.
{WARNING
Wet brakes can cause crashes.
They might not work as well in
a quick stop and could cause
pulling to one side. You could
lose control of the vehicle.
After driving through a large
puddle of water or a car/vehicle
wash, lightly apply the brake
pedal until the brakes work
normally.(Continued)
WARNING (Continued)
Flowing or rushing water creates
strong forces. Driving through
flowing water could cause your
vehicle to be carried away. If this
happens, you and other vehicle
occupants could drown. Do not
ignore police warnings and be
very cautious about trying to drive
through flowing water.
Hydroplaning
Hydroplaning is dangerous. Water
can build up under your vehicle's
tires so they actually ride on the
water. This can happen if the road
is wet enough and you are going
fast enough. When your vehicle is
hydroplaning, it has little or no
contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to
slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet
weather driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping
equipment in good shape.
.Keep the windshield washer fluid
reservoir filled.
.Have good tires with proper
tread depth. SeeTireson
page 10‑44.
.Turn off cruise control.
Highway Hypnosis
Always be alert and pay attention
to your surroundings while driving.
If you become tired or sleepy, find a
safe place to park your vehicle
and rest.

Driving and Operating 9-23
Other driving tips include:
.Keep the vehicle well ventilated.
.Keep interior temperature cool.
.Keep your eyes moving—scan
the road ahead and to the sides.
.Check the rearview mirror and
vehicle instruments often.
Hill and Mountain Roads
Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips for
driving in these conditions include:
.Keep the vehicle serviced and in
good shape.
.Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.Going down steep or long hills,
shift to a lower gear.
{WARNING
If you do not shift down, the
brakes could get so hot that they
would not work well. You would
then have poor braking or even
none going down a hill. You could
crash. Shift down to let the engine
assist the brakes on a steep
downhill slope.
{WARNING
Coasting downhill in N (Neutral)
or with the ignition off is
dangerous. The brakes will have
to do all the work of slowing down
and they could get so hot that
they would not work well. You
would then have poor braking or
even none going down a hill. You
could crash. Always have the
engine running and the vehicle in
gear when going downhill.
.Stay in your own lane. Do not
swing wide or cut across the
center of the road. Drive at
speeds that let you stay in your
own lane.
.Top of hills: Be alert —
something could be in your
lane (stalled car, accident).
.Pay attention to special road
signs (falling rocks area, winding
roads, long grades, passing or
no-passing zones) and take
appropriate action.

9-24 Driving and Operating
Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow
or ice between the tires and the
road, creating less traction or grip.
Wet ice can occur at about 0°C
(32°F) when freezing rain begins to
fall, resulting in even less traction.
Avoid driving on wet ice or in
freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the
condition. Accelerate gently so
traction is not lost. Accelerating too
quickly causes the wheels to spin
and makes the surface under the
tires slick, so there is even less
traction.
Try not to break the fragile traction.
If you accelerate too fast, the drive
wheels will spin and polish the
surface under the tires even more.The
Antilock Brake System (ABS)
on page 9‑50improves vehicle
stability during hard stops on
slippery roads, but apply the brakes
sooner than when on dry pavement.
Allow greater following distance on
any slippery road and watch for
slippery spots. Icy patches can
occur on otherwise clear roads in
shaded areas. The surface of a
curve or an overpass can remain icy
when the surrounding roads are
clear. Avoid sudden steering
maneuvers and braking while
on ice.
Turn off cruise control, if equipped,
on slippery surfaces.Blizzard Conditions
Being stuck in snow can be a
serious situation. Stay with the
vehicle unless there is help nearby.
If possible, use the Roadside
Service
on page 13‑5. To get help
and keep everyone in the
vehicle safe:
.Turn on the hazard warning
flashers.
.Tie a red cloth to an outside
mirror.
{WARNING
Snow can trap engine exhaust
under the vehicle. This may
cause exhaust gases to get
inside. Engine exhaust contains
carbon monoxide (CO) which
cannot be seen or smelled. It can
cause unconsciousness and even
death.
(Continued)

9-26 Driving and Operating
If the Vehicle is Stuck
Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
If stuck too severely for the traction
system to free the vehicle, turn the
traction system off and use the
rocking method.
{WARNING
If the 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 fire or other
damage. Spin the wheels as little
as possible and avoid going
above 55 km/h (35 mph) as
shown on the speedometer.
For information about using tire
chains on the vehicle, see Tire
Chains on page 10‑64.
Rocking the Vehicle to Get
it Out
Turn the steering wheel left and
right to clear the area around the
front wheels. Turn off any traction
system. Shift back and forth
between R (Reverse) and a forward
gear, or with a manual transmission,
between 1 (First) or 2 (Second) and
R (Reverse), 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 shifting, and press
lightly on the accelerator pedal
when the transmission is in gear.
Slowly spinning the wheels in the
forward and reverse directions
causes a rocking motion that could
free the vehicle. If that does not get
the vehicle out after a few tries, it
might need to be towed out. The
recovery loops can be used. If the
vehicle does need to be towed out,
see Towing the Vehicle
on
page 10‑90. Recovery Loops
{WARNING
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. The
vehicle could be damaged and
it would not be covered by the
vehicle warranty.

9-28 Driving and Operating
Tire and Loading Information
Label
Label Example
A vehicle specific Tire and
Loading Information label is
attached to the vehicle's center
pillar (B‐pillar). With the driver
door open, you will find the label
attached below the door latch
post. The Tire and Loading
Information label shows the
number of occupant seatingpositions (A), and the maximum
vehicle capacity weight (B) in
kilograms and pounds.
The Tire and Loading
Information label also shows
the size of the vehicle's original
equipment tires (C) and the
recommended cold tire inflation
pressures (D). For more
information on tires and inflation
see
Tires
on page 10‑44and Tire
Pressure
on page 10‑51.
There is also important
information on the Certification/
Tire label. It tells Gross Vehicle
Weight Rating (GVWR) and
the Gross Axle Weight Rating
(GAWR) for the front and rear
axles. See “Certification/Tire
Label” later in this section.
Steps for Determining Correct
Load Limit
1.
Locate the statement
“The combined weight of
occupants and cargo should
never exceed XXX kg or
XXX lbs” on your vehicle's
placard.
2.Determine the combined
weight of the driver and
passengers that will be riding
in your vehicle.
3.Subtract the combined
weight of the driver and
passengers from XXX kg or
XXX lbs.