2007 HUMMER H3 Owners Manual

{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.
Scanning the Terrain
Off-road driving can take you over many different
kinds of terrain. You need to be familiar with
the terrain and its many different features.
Here are some things to consider.
Surface Conditions:Off-roading can take you
over hard-packed dirt, gravel, rocks, grass, sand,
mud, snow, or ice. Each of these surfaces affects
the steering, acceleration, and braking of your
vehicle in different ways. Depending upon the kind
of surface you are on, you may experience slipping,
sliding, wheel spinning, delayed acceleration,
poor traction, and longer braking distances.Surface Obstacles:Unseen or hidden obstacles
can be hazardous. A rock, log, hole, rut, or bump
can startle you if you are not prepared for them.
Often these obstacles are hidden by grass, bushes,
snow, or even the rise and fall of the terrain itself.
Here are some things to consider:
Is the path ahead clear?
Will the surface texture change abruptly
up ahead?
Does the travel take you uphill or downhill?
There is more discussion of these subjects
later.
Will you have to stop suddenly or change
direction quickly?
When you drive over obstacles or rough terrain,
keep a rm grip on the steering wheel. Ruts,
troughs, or other surface features can jerk
the wheel out of your hands if you are not
prepared.
When possible, it is a good practice to survey
the landscape ahead on foot prior to driving
to observe hidden obstacles.
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When you drive over bumps, rocks, or other
obstacles, your wheels can leave the ground.
If this happens, even with one or two wheels, you
cannot control the vehicle as well or at all.
Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
In a way, off-road driving requires a different kind
of alertness from driving on paved roads and
highways. There are no road signs, posted speed
limits, or signal lights. You have to use your
own good judgment about what is safe and
what is not.
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. SeeDrunken Driving on page 235.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 degrees
minimum approach (A), 75 degrees 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.
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Roll Your 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, your vehicle will
cross logs up to 10 inches (25.4 cm) in diameter.
Approach the log at approximately a 15 degree
angle (A) with the transmission in FIRST (1)
and the transfer case in Four-Wheel-Low Lock
and “walk” your vehicle over, one tire at a time.
It may be necessary to modulate your brake
pedal and accelerator to avoid spin-out. Ease
the vehicle down from the log with your brake.
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Driving on Off-Road 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 your
vehicle can and cannot do. There are some hills
that simply cannot be driven, no matter how
well built the vehicle.
{CAUTION:
Many hills are simply too steep for any
vehicle. If you drive up them, you will
stall. If you drive down them, you cannot
control your speed. If you drive across
them, you will roll over. You could be
seriously injured or killed. If you have
any doubt about the steepness, do not
drive the hill.
Approaching a Hill
When you approach a hill, you need to decide if it
is one of those hills that is just too steep to climb,
descend, or cross. Steepness can be hard to judge.
On a very small hill, for example, there may be a
smooth, constant incline with only a small change in
elevation where you can easily see all the way to
the top. On a large hill, the incline may get steeper
as you near the top, but you may not see this
because the crest of the hill is hidden by bushes,
grass, or shrubs.
Here are some other things to consider as you
approach a hill:
Is there a constant incline, or does the hill get
sharply steeper in places?
Is there good traction on the hillside, or will
the surface cause tire slipping?
Is there a straight path up or down the hill so
you will not have to make turning maneuvers?
Are there obstructions on the hill that can
block your path, such as boulders, trees, logs,
or ruts?
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What is beyond the hill? Is there a cliff, an
embankment, a drop-off, a fence? Get out and
walk the hill if you do not know. It is the smart
way to nd out.
Is the hill simply too rough? Steep hills often
have ruts, gullies, troughs, and exposed rocks
because they are more susceptible to the
effects of erosion.
Driving Uphill
Once you decide you can safely drive up the hill,
you need to take some special steps:
Use transmission and transfer case low gear
and get a rm grip on the steering wheel.
Get a smooth start up the hill and try to
maintain your speed. Do not use more power
than you need, because you do not want
your wheels to start spinning or sliding.
Let the traction system work to control any
wheel slippage. The traction control system
allows for moderate wheel spin with some
capability to dig in and power up the hill.
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 your vehicle warranty.
Try to drive straight up the hill if at all possible.
If the path twists and turns, you might want
to nd another route.
{CAUTION:
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.
Ease up on your speed as you approach the
top of the hill.
Attach a ag to the vehicle to make you more
visible to approaching traffic on trails or hills.
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Sound the horn as you approach the top
of the hill to let opposing traffic know you
are there.
Use your headlamps even during the day.
They make you more visible to oncoming
traffic.
{CAUTION:
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.
Q:What should I do if my vehicle stalls,
or is about to stall, and I cannot make
it up the hill?
A:If this happens, there are some things
you should do, and there are some things
you must not do. First, here is what you
shoulddo:
Push the brake pedal to stop the vehicle
and keep it from rolling backwards. Also,
apply the parking brake.
If your engine is still running, shift the
transmission to REVERSE (R), release
the parking brake, and slowly back down
the hill in REVERSE (R).
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If your engine has stopped running, you will
need to restart it. With the brake pedal
pressed, apply the parking brake. If you
have an automatic transmission, shift the
transmission to PARK (P). Restart the engine.
Then, shift to REVERSE (R), release the
parking brake, and slowly back down the hill
as straight as possible in REVERSE (R).
As you are backing down the hill, put your
left hand on the steering wheel at the
12 o’clock position. This way, you will be
able to tell if your wheels are straight
and maneuver as you back down. It is
best that you back down the hill with your
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.Here are some things youmust notdo if you stall,
or are about to stall, when going up a hill:
Never attempt to prevent a stall by shifting
into NEUTRAL (N) to rev-up the engine
and regain forward momentum. This will
not work. Your vehicle will roll backwards very
quickly and you could go out of control.
Instead, apply the regular brake to stop the
vehicle. Then apply the parking brake. Shift to
REVERSE (R), release the parking brake,
and slowly back straight down.
Never attempt to turn around if you are
about to stall when going up a hill. If the hill
is steep enough to stall your vehicle, it is steep
enough to cause you to roll over if you turn
around. If you cannot make it up the hill,
you must back straight down the hill.
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Q:Suppose, after stalling, I try to back down
the hill and decide I just cannot do it.
What should I do?
A:Set the parking brake. If you have an
automatic transmission, shift to PARK (P).
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.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P), or, if you
have a manual transmission, even if you
are in gear. This is because the NEUTRAL
position on the transfer case overrides
the transmission. You or someone else
CAUTION: (Continued)
CAUTION: (Continued)
could be injured. If you are going to leave
your vehicle, set the parking brake and
shift the transmission to PARK (P), or,
put the manual transmission in FIRST (1).
But do not shift the transfer case to
NEUTRAL. Leave the transfer case in the
Four-Wheel High, Four-Wheel-High Lock,
or Four-Wheel-Low Lock position.
Driving Downhill
When off-roading takes you downhill, you will want
to consider a number of things:
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?
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