2010 HUMMER H3 engine

9-4 Driving and Operating
That could be a lot of distance in
an emergency, so keeping enough
space between the vehicle and
others is important.
And, of course, actual stopping
distances vary greatly with the
surface of the road, whether it is
pavement or gravel; the condition
of the road, whether it is wet, dry,
or icy; tire tread; the condition of the
brakes; the weight of the vehicle;
and the amount of brake force
applied.
Avoid needless heavy
braking. Some people drive in
spurts—heavy acceleration
followed by heavy braking —rather
than keeping pace with traffic. This
is a mistake. The brakes might not
have time to cool between hard
stops. The brakes will wear out
much faster with a lot of heavy
braking. Keeping pace with the
traffic and allowing realistic following
distances eliminates a lot of
unnecessary braking. That means
better braking and longer brake life. If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. If the brakes are pumped,
the pedal could get harder to push
down. If the engine stops, there will
still be some power brake assist but
it will be used when the brake is
applied. Once the power assist is
used up, it can take longer to stop
and the brake pedal will be harder
to push.
Adding non‐dealer/non‐retailer
accessories can affect vehicle
performance. See
Accessories and
Modifications on page 10‑3.
Steering
Power Steering
If power steering assist is lost
because the engine stops or the
power steering 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.

Driving and Operating 9-11
The vehicle can climb a 40.6 cm
(16 inch) 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 completestop. 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 first 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.

9-12 Driving and Operating
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 thebrakes.
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.
{WARNING
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.

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.

9-16 Driving and Operating
.Do not continue if the vehicle
shudders or exhibits suspension
hopping. This can cause
damage to the driveline or
suspension components.
Improper driving technique is not
covered by the vehicle warranty.
{WARNING
Turning or driving across steep
hills can be dangerous. You could
lose traction, slide sideways, and
possibly roll over. You could be
seriously injured or killed. When
driving up hills, always try to go
straight up.
.Try to drive straight up the hill if
at all possible. If the path twists
and turns, you might want to find
another route.
.Ease up on the speed as you
approach the top of the hill.
.Attach a flag to the vehicle to be
more visible to approaching
traffic on trails or hills.
.Sound the horn as you approach
the top of the hill to let opposing
traffic know you are there.
.Use headlamps even during the
day to make the vehicle more
visible to oncoming traffic.
{WARNING
Driving to the top (crest) of a
hill at full speed can cause an
accident. There could be a
drop-off, embankment, cliff,
or even another vehicle. You
could be seriously injured or
killed. As you near the top of a
hill, slow down and stay alert.If the vehicle stalls, or is about to
stall, and you cannot make it up
the hill:
.Push the brake pedal to stop
the vehicle and keep it from
rolling backwards and apply the
parking brake.
.If the engine is still running, shift
the transmission to R (Reverse),
release the parking brake, and
slowly back down the hill in
R (Reverse).
.If the engine has stopped
running, you need to restart it.
With the brake pedal pressed,
apply the parking brake. If the
vehicle has an automatic
transmission, shift the
transmission to P (Park).
Restart the engine. Then, shift
to R (Reverse), release the
parking brake, and slowly back
down the hill as straight as
possible in R (Reverse).

Driving and Operating 9-17
.While backing down the hill, put
your left hand on the steering
wheel at the 12 o'clock position
so you can tell if the wheels are
straight and can maneuver as
you back down. It is best to back
down the hill with the wheels
straight rather than in the left or
right direction. Turning the wheel
too far to the left or right will
increase the possibility of a
rollover.
Things not to do if the vehicle stalls,
or is about to stall, when going up
a hill:
.Never attempt to prevent a stall
by shifting into N (Neutral) to
rev-up the engine and regain
forward momentum. This will
not work. The vehicle can roll
backward very quickly and could
go out of control.
.Never try to turn around if about
to stall when going up a hill.
If the hill is steep enough to stall
the vehicle, it is steep enough
to cause it to roll over. If you
cannot make it up the hill, back
straight down the hill.
If, after stalling, you try to back
down the hill and decide you just
cannot do it, set the parking brake.
If the vehicle has an automatic
transmission, shift to P (Park). Turn
off the engine. Leave the vehicle
and go get some help. Exit on the
uphill side and stay clear of the path
the vehicle would take if it rolled
downhill. Do not shift the transfer
case to Neutral when you leave the
vehicle. Leave it in some gear.
{WARNING
Shifting the transfer case to
Neutral can cause your vehicle to
roll even if the transmission is in
P (Park). This is because the
Neutral position on the transfer
case overrides the transmission.
You or someone else could be
injured. If you are going to leave
your vehicle, set the parking
brake and shift the transmission
to P (Park). But do not shift the
transfer case to Neutral.

9-18 Driving and Operating
Driving Downhill
When off-roading takes you
downhill, consider:
.How steep is the downhill?
Will I be able to maintain vehicle
control?
.What is the surface like?
Smooth? Rough? Slippery?
Hard-packed dirt? Gravel?
.Are there hidden surface
obstacles? Ruts? Logs?
Boulders?
.What is at the bottom of the hill?
Is there a hidden creek bank or
even a river bottom with large
rocks?
If you decide you can go down
a hill safely, try to keep the vehicle
headed straight down. Use a low
gear so engine drag can help the
brakes so they do not have to do all
the work. Descend slowly, keeping
the vehicle under control at all
times.
{WARNING
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and a
serious accident. Apply the
brakes lightly when descending a
hill and use a low gear to keep
vehicle speed under control.
Things not to do when driving down
a hill:
.When driving downhill, avoid
turns that take you across the
incline of the hill. A hill that is not
too steep to drive down might be
too steep to drive across. The
vehicle could roll over.
.Never go downhill with the
transmission in N (Neutral),
called free-wheeling. The brakes
will have to do all the work and
could overheat and fade. Vehicles are much more likely to
stall when going uphill, but if it
happens when going downhill:
1. Stop the vehicle by applying the
regular brakes and apply the
parking brake.
2. With an automatic transmission, shift to P (Park). 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.

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.