Accelerator HUMMER H3 2008 User Guide

Off-Road Recovery
You may nd that your right wheels have dropped off the
edge of a road onto the shoulder while you are 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 your vehicle straddles the edge of the
pavement. You can turn the steering wheel up to
one-quarter 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,
we suggest the following tips:
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.
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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 your 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.
A cornering skid is best handled by easing your foot
off the accelerator pedal.
Remember: Any traction control system helps avoid
only the acceleration skid. If your traction system is
off, then an acceleration skid is also best handled
by easing your foot off the accelerator pedal.
SeeTraction Control System (TCS) on page 4-5
andStabiliTrak
®System on page 4-7.If your 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,
your vehicle may straighten out. Always be ready
for a second skid if it occurs.
Of course, traction is reduced when water, snow, ice,
gravel, or other material is on the road. For safety,
you will want to 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 your 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.
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Your 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 FIRST (1) 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.
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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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You can run the engine to keep warm, but be careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see it
or smell it, so you might not know it is in your
vehicle. Clear away snow from around the
base of your vehicle, especially any that is
blocking the exhaust pipe. And check around
again from time to time to be sure snow does
not collect there.
Open a window just a little on the side of the
vehicle that is away from the wind. This will
help keep CO out.
Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well-charged battery to
restart the vehicle, and possibly for signaling later on with
the headlamps. Let the heater run for a while.
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Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right to clear
the area around the front wheels. The traction control
system activates when the system senses that the
wheels are spinning. Turn off any traction or stability
system. SeeTraction Control System (TCS) on page 4-5
andStabiliTrak
®System on page 4-7. Then, with the
wheels straight ahead, shift back and forth between
REVERSE (R) and a forward gear, or with a manual
transmission, between FIRST (1) or SECOND (2)
and REVERSE (R), 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 you shift, and press lightly
on the accelerator pedal when the transmission is
in gear. By slowly spinning the wheels in the forward
and reverse directions, you will cause a rocking motion
that could free your vehicle. If that does not get your
vehicle out after a few tries, it might need to be towed
out. Or, you can use the recovery loops. If your
vehicle does need to be towed out, seeTowing
Your Vehicle on page 4-48.
Recovery Loops
{CAUTION:
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. Your vehicle could be damaged and it would
not be covered by warranty.
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If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about 10 minutes.
If the warning does not come back on, you can drive
normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there is still no sign of steam, idle the engine for
three minutes while you are parked. Push down
the accelerator until the engine speed is about twice as
fast as normal idle speed for at least three minutes
while you are parked. If you still have the warning, turn
off the engine and get everyone out of the vehicle
until it cools down.
You may decide not to lift the hood but to get service
help right away.Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Engine Cooling Fan
C. Radiator Pressure Cap
If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.3.7L Engine shown, 5.3L Engine similar
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When the engine is cold, the coolant level should be at
least up to the FULL COLD mark. If it is not, you
may have a leak at the pressure cap or in the radiator
hoses, heater hoses, radiator, water pump or
somewhere else in the cooling system.
{CAUTION:
Heater and radiator hoses, and other engine
parts, can be very hot. Do not touch them. If
you do, you can be burned.
Do not run the engine if there is a leak. If you
run the engine, it could lose all coolant. That
could cause an engine re, and you could be
burned. Get any leak xed before you drive the
vehicle.
If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it does not, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running the engine
without coolant is not covered by the warranty.
Notice:Using coolant other than DEX-COOL
®may
cause premature engine, heater core, or radiator
corrosion. In addition, the engine coolant could
require changing sooner, at 30,000 miles (50 000 km)
or 24 months, whichever occurs rst. Any repairs
would not be covered by the warranty. Always
use DEX-COOL
®(silicate-free) coolant in the vehicle.
5-32

If a Tire Goes Flat
It is unusual for a tire to blowout while you are driving,
especially if you maintain your vehicle’s tires properly.
If air goes out of a tire, it is much more likely to leak out
slowly. But if you should ever have a blowout, here
are a few tips about what to expect and what to do:
If a front tire fails, the at tire creates a drag that pulls
the vehicle toward that side. Take your foot off the
accelerator pedal and grip the steering wheel rmly.
Steer to maintain lane position, and then gently brake to
a stop well out of the traffic lane.
A rear blowout, particularly on a curve, acts much like a
skid and may require the same correction you would
use in a skid. In any rear blowout remove your foot from
the accelerator pedal. Get the vehicle under control
by steering the way you want the vehicle to go. It may
be very bumpy and noisy, but you can still steer. Gently
brake to a stop, well off the road if possible.{CAUTION:
Lifting a vehicle and getting under it to do
maintenance or repairs is dangerous without
the appropriate safety equipment and training.
The jack provided with your vehicle is
designed only for changing a at tire. If it is
used for anything else, you or others could be
badly injured or killed if the vehicle slips off
the jack. Use the jack provided with your
vehicle only for changing a at tire.
If a tire goes at, the next part shows how to use the
jacking equipment to change a at tire safely.
5-78

At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-32.
Do not use the accelerator pedal, and be ready to
turn off the engine immediately if it starts.
3. On automatic transmission vehicles, try to start the
engine in each gear. The vehicle should start only
in PARK (P) or NEUTRAL (N). If the vehicle
starts in any other position, contact your
dealer/retailer for service.
On manual transmission vehicles, put the shift lever
in NEUTRAL, push the clutch pedal down halfway,
and try to start the engine. The vehicle should
start only when the clutch pedal is pushed down all
the way to the oor.If the vehicle starts when the clutch pedal is not
pushed all the way down, contact your
dealer/retailer for service.
Automatic Transmission Shift Lock
Control System Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle. It should be parked on a level
surface.
2. Firmly apply the parking brake. SeeParking Brake
on page 2-32.
Be ready to apply the regular brake immediately if
the vehicle begins to move.
3. With the engine off, turn the ignition to ON/RUN,
but do not start the engine. Without applying the
regular brake, try to move the shift lever out
of PARK (P) with normal effort. If the shift lever
moves out of PARK (P), contact your dealer/retailer
for service.
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