light HUMMER H3 2007 Owners Manual

Brake Wear
Your vehicle has four-wheel disc brakes.
Disc brake pads have built-in wear indicators that
make a high-pitched warning sound when the
brake pads are worn and new pads are needed.
The sound may come and go or be heard all
the time your vehicle is moving, except when you
are pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.
Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates may cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with your brakes.Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated,
inspect brake pads for wear and evenly tighten
wheel nuts in the proper sequence to GM torque
specications.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not
return to normal height, or if there is a rapid
increase in pedal travel. This could be a sign
of brake trouble.
Brake Adjustment
Every time you make a brake stop, your disc
brakes adjust for wear.
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Notice:If the other vehicle’s system is not a
12-volt system with a negative ground,
both vehicles can be damaged. Only use
vehicles with 12-volt systems with negative
grounds to jump start your vehicle.
2. Get the vehicles close enough so the jumper
cables can reach, but be sure the vehicles are
not touching each other. If they are, it could
cause a ground connection you do not
want. You would not be able to start your
vehicle, and the bad grounding could damage
the electrical systems.
To avoid the possibility of the vehicles rolling,
set the parking brake rmly on both vehicles
involved in the jump start procedure. Put
an automatic transmission in PARK (P) or a
manual transmission in NEUTRAL before
setting the parking brake. If you have a
four-wheel-drive vehicle, be sure the transfer
case is not in NEUTRAL.Notice:If you leave your radio or other
accessories on during the jump starting
procedure, they could be damaged. The repairs
would not be covered by your warranty.
Always turn off your radio and other
accessories when jump starting your vehicle.
3. Turn off the ignition on both vehicles.
Unplug unnecessary accessories plugged into
the cigarette lighter or the accessory power
outlets. Turn off the radio and all lamps
that are not needed. This will avoid sparks
and help save both batteries. And it could
save the radio!
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4. Open the hoods and locate the batteries on
both vehicles. You will use the positive (+)
battery terminal and the remote negative (−)
jump starting terminal to jump start your
vehicle. To access the positive (+) battery
terminal, open the terminal cover. SeeEngine
Compartment Overview on page 322for
more information on the terminal locations.
{CAUTION:
Using a match near a battery can cause
battery gas to explode. People have been
hurt doing this, and some have been
blinded. Use a ashlight if you need
more light.
CAUTION: (Continued)
CAUTION: (Continued)
Be sure the batteries have enough water.
You do not need to add water to the
ACDelco
®battery (or batteries) installed in
your new vehicle. But if a battery has ller
caps, be sure the right amount of uid is
there. If it is low, add water to take care of
that rst. If you do not, explosive gas
could be present.
Battery uid contains acid that can burn
you. Do not get it on you. If you
accidentally get it in your eyes or on your
skin, ush the place with water and get
medical help immediately.
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The vehicle should be properly prepared as follows:
The vehicle should be placed so the headlamps
are 25 ft. (7.6 m) from a light colored wall or
other at surface.
The vehicle must have all four tires on a level
surface which is level all the way to the wall or
other at surface.
The vehicle should be placed so it is
perpendicular to the wall or other at surface.
The vehicle should not have any snow, ice, or
mud on it.
The vehicle should be fully assembled and all
other work stopped while headlamp aiming is
being performed.
The vehicle should be normally loaded with a
full tank of fuel and one person or 160 lbs
(75 kg) sitting on the driver’s seat.
Tires should be properly inated.
The spare tire is in its original location in
the vehicle.To adjust the vertical aim, do the following:
1. Open the hood. SeeHood Release on
page 321for more information.
2. Find the aim dot on the lens of the headlamp.
3. Measure the distance from the ground to
the aim dot on the headlamp. Record the
distance.
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4. At the wall or other at surface, measure from
the ground upward the recorded distance from
Step 2 and mark it.
5. Draw or tape a horizontal line the width of the
vehicle at the wall or other at surface where
it was marked it Step 4.
Notice:Do not cover a headlamp to improve
beam cut-off when aiming. Covering a
headlamp may cause excessive heat build-up
which may cause damage to the headlamp.
6. Turn on the headlamps and place a piece of
cardboard or equivalent in front of the
headlamp not being aimed. This should allow
only the beam of light from the headlamp
being aimed to be seen on the at surface.7. Locate the vertical headlamp aiming screws,
which are under the hood near each headlamp
assembly.
The adjustment screw can be turned with an
E8 Torx
®socket or T15 Torx®screwdriver.
Passenger’s Side Shown
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(E) Tire Ply Material:The type of cord and
number of plies in the sidewall and under
the tread.
(F) Uniform Tire Quality Grading (UTQG):
Tire manufacturers are required to grade
tires based on three performance factors:
treadwear, traction, and temperature resistance.
For more information, seeUniform Tire Quality
Grading on page 386.
(G) Maximum Cold Ination Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.
For information on recommended tire pressure
seeInation - Tire Pressure on page 375
andLoading Your Vehicle on page 289.
(A) Tire Size:The tire size code is a combination
of letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.
Light Truck (LT-Metric) Tire
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Tire Size
The following examples show the different parts of
a tire size.
(A) Passenger (P-Metric) Tire:The United
States version of a metric tire sizing system.
The letter P as the rst character in the tire size
means a passenger vehicle tire engineered
to standards set by the U.S. Tire and Rim
Association.(A) Light Truck (LT-Metric) Tire:The United
States version of a metric tire sizing system.
The letters LT as the rst two characters in the
tire size means a light truck tire engineered
to standards set by the U.S. Tire and Rim
Association.
(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
(C) Aspect Ratio:A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 75, as
shown in item C of the light truck (LT-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 percent as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire.
The letter R means radial ply construction;
the letter D means diagonal or bias ply
construction; and the letter B means belted-bias
ply construction.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
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GAWR FRT:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 289.
GAWR RR:Gross Axle Weight Rating for the
rear axle. SeeLoading Your Vehicle on page 289.
Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa):The metric unit for air pressure.
Light Truck (LT-Metric) Tire:A tire used on
light duty trucks and some multipurpose passenger
vehicles.
Load Index:An assigned number ranging from
1 to 279 that corresponds to the load carrying
capacity of a tire.
Maximum Ination Pressure:The maximum
air pressure to which a cold tire may be inated.
The maximum air pressure is molded onto the
sidewall.
Maximum Load Rating:The load rating for a tire
at the maximum permissible ination pressure
for that tire.Maximum Loaded Vehicle Weight:The sum of
curb weight, accessory weight, vehicle capacity
weight, and production options weight.
Normal Occupant Weight:The number of
occupants a vehicle is designed to seat multiplied
by 150 lbs (68 kg). SeeLoading Your Vehicle
on page 289.
Occupant Distribution:Designated seating
positions.
Outward Facing Sidewall:The side of an
asymmetrical tire that has a particular side that
faces outward when mounted on a vehicle.
The side of the tire that contains a whitewall, bears
white lettering, or bears manufacturer, brand,
and/or model name molding that is higher
or deeper than the same moldings on the other
sidewall of the tire.
Passenger (P-Metric) Tire:A tire used on
passenger cars and some light duty trucks and
multipurpose vehicles.
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How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are
properly inated simply by looking at them. Radial
tires may look properly inated even when they
are underinated. Check the tire’s ination
pressure when the tires are cold. Cold means your
vehicle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Remove the valve cap from the tire valve stem.
Press the tire gage rmly onto the valve to
get a pressure measurement. If the cold tire
ination pressure matches the recommended
pressure on the Tire and Loading Information
label, no further adjustment is necessary. If the
ination pressure is low, add air until you reach the
recommended amount.
If you overll the tire, release air by pushing on
the metal stem in the center of the tire valve.
Recheck the tire pressure with the tire gage.
Be sure to put the valve caps back on the valve
stems. They help prevent leaks by keeping out dirt
and moisture.
Tire Pressure Monitor System
Your vehicle has a Tire Pressure Monitor System
(TPMS). This system uses radio and sensor
technology to check tire pressure levels. TPMS
sensors are mounted onto each tire and wheel
assembly on your vehicle, including the spare tire.
The TPMS sensors monitor the air pressure in
your vehicle’s tires and transmit the tire pressure
readings to a receiver located in the vehicle.
When a low tire pressure condition is detected,
the TPMS will illuminate the low tire pressure
warning light located in the instrument panel
cluster, and at the same time display the LOW
TIRE warning message on the Driver Information
Center (DIC). The low tire pressure warning
light and the LOW TIRE warning message appear
at each ignition cycle until the tires are inated
to the correct ination pressure.
376

For additional information and details about the
DIC operation and displays seeDIC Controls and
Displays on page 192andDIC Warnings and
Messages on page 196.
You may notice, during cooler weather conditions,
that the low tire pressure warning light and the
DIC LOW TIRE message may come on when the
vehicle is rst started, and then turn off as you
start to drive. This may be an early indicator that
the air pressure in the tire(s) is getting low
and needs to be inated to the proper pressure.
Each tire, including the spare (if provided), should
be checked monthly when cold and inated to
the ination pressure recommended by the vehicle
manufacturer on the vehicle placard or tire
ination pressure label. (If your vehicle has tires of
a different size than the size indicated on the
vehicle placard or tire ination pressure label, you
should determine the proper tire ination
pressure for those tires.)As an added safety
feature, your vehicle
has been equipped with
a tire pressure
monitoring system
(TPMS) that illuminates
a low tire pressure
telltale when one
or more of your tires is
signicantly
under-inated.
Accordingly, when the low tire pressure telltale
illuminates, you should stop and check your tires
as soon as possible, and inate them to the
proper pressure. Driving on a signicantly
under-inated tire causes the tire to overheat and
can lead to tire failure. Under-ination also
reduces fuel efficiency and tire tread life, and may
affect the vehicle’s handling and stopping ability.
Please note that the TPMS is not a substitute for
proper tire maintenance, and it is the driver’s
responsibility to maintain correct tire pressure, even
if under-ination has not reached the level to trigger
illumination of the TPMS low tire pressure telltale.
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