HUMMER H3 2007 Owners Manual

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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If you decide you can go down a hill safely, then
try to keep your vehicle headed straight down, and
use a low gear. This way, engine drag can help
your brakes and they will not have to do all
the work. Descend slowly, keeping your vehicle
under control at all times.
{CAUTION:
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.
Q:Are there some things I should not do
when driving down a hill?
A:Yes! These are important because if you
ignore them you could lose control and
have a serious accident:
When driving downhill, avoid turns that take
you across the incline of the hill. A hill that
is not too steep to drive down may be
too steep to drive across. You could roll over
if you do not drive straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
Your brakes will have to do all the work
and could overheat and fade.
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Q:Am I likely to stall when going downhill?
A:It is much more likely to happen going uphill.
But if it happens going downhill, here is
what to do:
1. Stop your vehicle by applying the regular
brakes. Apply the parking brake.
2. If you have an automatic transmission,
shift to PARK (P). 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 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:
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.
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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.
{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.
Q:What if I am driving across an incline
that is not too steep, but I hit some
loose gravel and start to slide downhill.
What should I do?
A: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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Stalling on an Incline
If your vehicle stalls when you are 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.
{CAUTION:
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.
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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.
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Driving in 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.
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.{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.
SeeDriving in Rain and on Wet Roads on page 273
for more information on driving through water.
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