HUMMER H3 2009 Owners Manual

2. Press the rear axle locking
button with the vehicle moving
less than 16 mph (26 km/h).
The light in the button stops ashing
and remains illuminated when the
rear axle is locked.
Notice:If you try to lock the axle
while the vehicle is stuck and
the tires are spinning, the
vehicle’s drivetrain could be
damaged. The repairs would not
be covered by the vehicle
warranty. Always lock the axle
before attempting situations
and/or navigating terrain which
could possibly cause the vehicle
to become stuck.
The locking rear axle will be
disengaged when the wheel speed
is greater than 40 mph (64 km/h),
if the vehicle’s battery is low and/or
the transfer case is shifted out of
4LO Lock mode.Notice:If the vehicle’s axle is
locked while driving on pavement,
the drivetrain could be damaged.
Repairs would not be covered
by the vehicle warranty. Do
not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.
Locking Front Axle
For vehicles with this feature, the
locking front axle, used with
the locking rear axle, can give the
vehicle additional traction when
traveling in off-road situations such
as mud, snow, sand, steep hills
and uneven terrain.
The button used to turn the locking
front axle on or off is located on
the instrument panel.Before the front axle can be locked,
the rear axle must be locked.
To lock the front and rear axles:
1. Place the transfer case in
the 4LO Lock mode. This is the
only mode which allows the
front and rear axles to lock. See
Full-Time Four-Wheel Drive
on page 2-24for more
information regarding the transfer
case and 4LO Lock mode.
2. Press the rear axle locking
button with the vehicle moving
less than 16 mph (26 km/h).
3. Wait for the light in the button
to stop ashing and remain
illuminated to show that the rear
axle is locked.
4. Press the front axle locking
button with the vehicle stopped
or moving less than 16 mph
(26 km/h).
Driving Your Vehicle 4-9

5. Wait for the light in the button
to stop ashing and remain
illuminated to show that the front
axle is locked.
Notice:If you try to lock the axle
while the vehicle is stuck and
the tires are spinning, the
vehicle’s drivetrain could be
damaged. The repairs would not
be covered by the vehicle
warranty. Always lock the axle
before attempting situations
and/or navigating terrain which
could possibly cause the vehicle
to become stuck.
Locking axles will be disengaged
when the wheel speed is greater
than 40 mph (64 km/h), if the
vehicle’s battery is low and/or the
transfer case is shifted out of
4LO Lock mode.Notice:If the vehicle’s axle is
locked while driving on pavement,
the drivetrain could be damaged.
Repairs would not be covered
by the vehicle warranty. Do
not use the locking axle on
pavement. If four-wheel drive is
needed when traveling on
pavement, use only 4HI.
Steering
Power Steering
If power steering assist is lost
because the engine stops or the
system is not functioning, the vehicle
can be steered but it will take
more effort.
Steering Tips
It is important to take curves at a
reasonable speed.
Traction in a curve depends on the
condition of the tires and the
road surface, the angle at which the
curve is banked, and vehicle
speed. While in a curve, speed is
the one factor that can be controlled.
If there is a need to reduce speed,
do it before entering the curve,
while the front wheels are straight.
Try to adjust the speed so you
can drive through the curve.
Maintain a reasonable, steady
speed. Wait to accelerate until out
of the curve, and then accelerate
gently into the straightaway.
4-10 Driving Your Vehicle

Steering in Emergencies
There are times when steering can
be more effective than braking.
For example, you come over a hill
and nd a truck stopped in your
lane, or a car suddenly pulls
out from nowhere, or a child darts
out from between parked cars
and stops right in front of you. These
problems can be avoided by
braking — if you can stop in time.
But sometimes you cannot stop
in time because there is no room.
That is the time for evasive
action —steering around the
problem.
The vehicle can perform very well in
emergencies like these. First
apply the brakes. SeeBraking on
page 4-3. It is better to remove
as much speed as possible from a
collision. Then steer around the
problem, to the left or right
depending on the space available.An emergency like this requires
close attention and a quick decision.
If holding the steering wheel at
the recommended 9 and 3 o’clock
positions, it can be turned a full
180 degrees very quickly without
removing either hand. But you have
to act fast, steer quickly, and just
as quickly straighten the wheel once
you have avoided the object.
The fact that such emergency
situations are always possible is a
good reason to practice defensive
driving at all times and wear
safety belts properly.
Off-Road Recovery
The vehicle’s right wheels can drop
off the edge of a road onto the
shoulder while driving.
If the level of the shoulder is only
slightly below the pavement,
recovery should be fairly easy. Ease
off the accelerator and then, if
there is nothing in the way, steer
so that the vehicle straddles
the edge of the pavement.
Driving Your Vehicle 4-11

Turn the steering wheel 3 to
5 inches, 8 to 13 cm, (about
one-eighth turn) until the right front
tire contacts the pavement edge.
Then turn the steering wheel to go
straight down the roadway.
Passing
Passing another vehicle on a
two-lane road can be dangerous. To
reduce the risk of danger while
passing:
Look down the road, to the sides,
and to crossroads for situations
that might affect a successful
pass. If in doubt, wait.
Watch for traffic signs,
pavement markings, and lines
that could indicate a turn or
an intersection. Never cross a
solid or double-solid line on your
side of the lane.
Do not get too close to the
vehicle you want to pass. Doing
so can reduce your visibility.
Wait your turn to pass a slow
vehicle.
When you are being passed,
ease to the right.
Loss of Control
Let us review what driving experts
say about what happens when
the three control systems — brakes,
steering, and acceleration — do
not have enough friction where the
tires meet the road to do what
the driver has asked.
In any emergency, do not give up.
Keep trying to steer and constantly
seek an escape route or area of
less danger.
Skidding
In a skid, a driver can lose control
of the vehicle. Defensive drivers
avoid most skids by taking
reasonable care suited to existing
conditions, and by not overdriving
those conditions. But skids are
always possible.The three types of skids
correspond to the vehicle’s three
control systems. In the braking
skid, the wheels are not rolling. In
the steering or cornering skid,
too much speed or steering in a
curve causes tires to slip and
lose cornering force. And in the
acceleration skid, too much
throttle causes the driving wheels
to spin.
Remember: Any traction control
system helps avoid only the
acceleration skid. If the traction
system is off, then an acceleration
skid is best handled by easing
your foot off the accelerator pedal.
SeeTraction Control System
(TCS) on page 4-7andStabiliTrak
®
System on page 4-6.
If the vehicle starts to slide, ease
your foot off the accelerator
pedal and quickly steer the way you
want the vehicle to go. If you
start steering quickly enough, the
vehicle may straighten out. Always
be ready for a second skid if it
occurs.
4-12 Driving Your Vehicle

Of course, traction is reduced when
water, snow, ice, gravel, or other
material is on the road. For safety,
slow down and adjust your
driving to these conditions. It is
important to slow down on slippery
surfaces because stopping
distance will be longer and vehicle
control more limited.
While driving on a surface with
reduced traction, try your best to
avoid sudden steering, acceleration,
or braking, including reducing
vehicle speed by shifting to a lower
gear. Any sudden changes could
cause the tires to slide. You may not
realize the surface is slippery until
the vehicle is skidding. Learn to
recognize warning clues — such as
enough water, ice, or packed
snow on the road to make a
mirrored surface — and slow down
when you have any doubt.
Remember: Any Antilock Brake
System (ABS) helps avoid only the
braking skid.Off-Road Driving
The airbag system is designed to
work properly under a wide range
of conditions, including off-road
usage. Always wear your safety belt
and observe safe driving speeds,
especially on rough terrain.
Drinking and driving can be very
dangerous on any road and this is
certainly true for off-road driving.
At the very time you need special
alertness and driving skills, your
reexes, perceptions, and judgment
can be affected by even a small
amount of alcohol. You could
have a serious — or even
fatal — accident if you drink and
drive or ride with a driver who has
been drinking.Off-roading can be great fun
but has some denite hazards. The
greatest of these is the terrain
itself. When off-road driving, traffic
lanes are not marked, curves are not
banked, and there are no road
signs. Surfaces can be slippery,
rough, uphill, or downhill.
Avoid sharp turns and abrupt
maneuvers. Failure to operate the
vehicle correctly off-road could result
in loss of vehicle control or vehicle
rollover.
Off-roading involves some new
skills. That is why it is very important
that you read these driving tips
and suggestions to help make
off-road driving safer and more
enjoyable.
Driving Your Vehicle 4-13

Before You Go Off-Roading

Have all necessary maintenance
and service work done.
Make sure there is enough fuel,
that uid levels are where they
should be, and that the spare tire
is fully inated.
Be sure to read all the
information about
four-wheel-drive vehicles in this
manual.
Make sure all underbody shields,
if the vehicle has them, are
properly attached.
Know the local laws that apply to
off-roading where you will be
driving or check with law
enforcement people in the area.
Be sure to get the necessary
permission if you will be on
private land.
Loading Your Vehicle for
Off-Road Driving
{CAUTION
Cargo on the load oor 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
oor can be tossed about
when driving over rough
terrain. You or your
passengers can be struck by
ying objects. Secure the
cargo properly.
(Continued)
CAUTION (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 oor, 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.
4-14 Driving Your Vehicle

You will nd other important
information underLoading the
Vehicle on page 4-35andTires on
page 5-44.
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, owers,
trees, or grasses or disturb
wildlife. This includes
wheel-spinning, breaking down
trees, or unnecessary driving
through streams or over
soft ground.
Always carry a litter bag and
make sure all refuse is removed
from any campsite before
leaving.
Take extreme care with open
res (where permitted), camp
stoves, and lanterns.
Never park your vehicle over dry
grass or other combustible
materials that could catch re
from the heat of the vehicle’s
exhaust system.
Traveling to Remote Areas
It makes sense to plan your
trip, especially when going to a
remote area. Know the terrain and
plan your route. Get accurate
maps of trails and terrain. Check to
see if there are any blocked or
closed roads.
It is also a good idea to travel
with at least one other vehicle in
case something happens to one
of them.
For vehicles with a winch, be sure
to read the winch instructions.
In a remote area, a winch can be
handy if you get stuck but you
will want to know how to use
it properly.
Driving Your Vehicle 4-15

High Mobility Characteristics
The H3 has a 8.8 inch (22.3 cm)
running ground clearance (A),
a 9.2 inch (23.4 cm) axle to ground
clearance (B), and a low center
of gravity.
The H3T has a 9.5 inch (24.1 cm)
running ground clearance (A),
and 8.7 inch (22.1 cm) axle to
ground clearance (B), and a low
center of gravity.
The H3 has an approximate
approach angle (A) of 37.4 degrees
and a departure angle (B) of
34.7 degrees, depending on
suspension packages.The H3T has an approximate
approach angle (A) of 37.1 degrees
and a departure angle (B) of
31 degrees, depending on
suspension packages.
Design specications required
a minimum gradeability of 60%
(31 degrees) slope, with the vehicle
fully loaded, on high friction
surfaces with maximum vehicle
speed not to exceed 6 mph
(9.7 km/h). The vehicle is expected
to traverse this grade only for
short durations. Never stop and idle
the vehicle or park it on this grade.
4-16 Driving Your Vehicle

The vehicle should be able to
traverse a 40% (22 degrees) side
slope at 6 mph (9.7 km/h) while fully
loaded on high friction surfaces.The vehicle can climb a
16 inch (40.6 cm) vertical step.
Step climbing is best done by
approaching the step at an angle
rather than straight on.
Brake and Accelerator
Operation Techniques for
Off-Road Driving
For logs, walls, rocks, severe
ditches, hills, sand, etc.
1. Bring the vehicle to a complete
stop. Do not rev the engine.
2. Select the proper transmission
and transfer case gear
range; usually 1 (First) gear,
Four-Wheel-Low Lock for such
obstacles.3. If wheel spin is experienced,
maintain steady throttle, with
your foot off the brake pedal, to
allow the Traction Control
System (TCS) to control the
wheel spin. TCS might not
operate if the brakes are applied.
4. If wheel spin cannot be controlled
by the TCS system, fully press
the brake pedal with your left foot
so all wheel spin is stopped.
5. Back away from the obstacle
so that a new approach can
be tried.
6. As the rst wheel crosses the
obstacle, be prepared to
alternate the brake and
accelerator pedal to maintain
control and avoid tire drop-off
from obstacles. Repeat this
process for the other wheels.
Driving Your Vehicle 4-17

For mounds, washouts, loose
up-hill slopes, ditches, etc.
When wheel spin occurs as the
vehicle is moving, the driver may
notice a slight shaking or shuddering
of the vehicle. This should be
stopped as soon as possible to
prevent damage to vehicle
components. This is the indication
that a loss of traction is occurring on
this terrain. The operator should:
1. Reduce speed and apply
the brakes.
2. Assess the terrain properly and
adjust vehicle speed and gear
ranges accordingly: Four-Wheel
High position for higher speeds
and Four-Wheel-Low Lock
for more torque and lower
speeds. Transmission 1 (First)
gear is generally recommended.3. Apply slight pressure to the
brake when the shaking or
shuddering sensation is felt,
keeping the vehicle moving in a
controlled manner.
4. Be prepared to alternate between
braking and accelerating through
the adverse terrain.
Getting Familiar with Off-Road
Driving
It is a good idea to practice in an
area that is safe and close to home
before you go into the wilderness.
Off-roading requires some new
and different skills.
Tune your senses to different
kinds of signals. Your eyes need
to constantly sweep the terrain
for unexpected obstacles. Your ears
need to listen for unusual tire or
engine sounds. Use your arms,
hands, feet, and body to respond to
vibrations and vehicle bounce.Controlling the vehicle is the key to
successful off-road driving. One of
the best ways to control the
vehicle is to control the speed.
At higher speeds:
You approach things faster and
have less time to react.
There is less time to scan the
terrain for obstacles.
The vehicle has more bounce
when driving over obstacles.
More braking distance is needed,
especially on an unpaved surface.
{CAUTION
When you are driving off-road,
bouncing and quick changes in
direction can easily throw you
out of position. This could cause
you to lose control and crash.
So, whether you are driving
on or off the road, you and
your passengers should wear
safety belts.
4-18 Driving Your Vehicle