width HUMMER H3 2009 Owners Manual

{CAUTION
You can be seriously injured by not
wearing the lap-shoulder belt
properly. In a crash, you would not
be restrained by the shoulder belt.
Your body could move too far
forward increasing the chance of
head and neck injury. You might
also slide under the lap belt.
The belt force would then be
applied right on the abdomen.
That could cause serious or fatal
injuries. The shoulder belt should
go over the shoulder and across
the chest.
Q:What is wrong with this?
A:The belt is twisted across
the body.
{CAUTION
You can be seriously injured by a
twisted belt. In a crash, you would
not have the full width of the belt
to spread impact forces. If a belt
is twisted, make it straight so it
can work properly, or ask your
dealer/retailer to x it.
Seats and Restraint System 1-19

Driving Across an Incline
An off-road trail will probably go
across the incline of a hill. To decide
whether to try to drive across the
incline, consider the following:
{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.
A hill that can be driven
straight up or down might be
too steep to drive across. When
going straight up or down a
hill, the length of the wheel
base — the distance from
the front wheels to the rear
wheels —reduces the likelihoodthe vehicle will tumble end over
end. But when driving across
an incline, the narrower
track width — the distance
between the left and right
wheels — might not prevent the
vehicle from tilting and rolling
over. Driving across an incline
puts more weight on the downhill
wheels which could cause a
downhill slide or a rollover.
Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the 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, the vehicle can tilt
even more.
For these reasons, carefully
consider 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.
If you feel the vehicle starting to
slide sideways, turn downhill. This
should help straighten out the
vehicle and prevent the side
slipping. The best way to prevent
this is to “walk the course” rst,
so you know what the surface is like
before driving it.
Driving Your Vehicle 4-25

To adjust the vertical aim:
1. Open the hood. SeeHood
Release on page 5-9.
2. Record the distance from the
ground to the aim dot on the
headlamp.3. At a wall, measure from the
ground upward the recorded
distance from Step 2 and mark it.
4. Draw or tape a horizontal line the
width of the vehicle at the wall
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.
5. 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 wall.
6. 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 Side Shown
5-40 Service and Appearance Care

CAUTION (Continued)
Underinated tires pose
the same danger as
overloaded tires. The
resulting accident could
cause serious injury.
Check all tires frequently to
maintain the recommended
pressure. Tire pressure
should be checked when
your vehicle’s tires are
cold. SeeInflation - Tire
Pressure on page 5-51.
Overinated tires are more
likely to be cut, punctured,
or broken by a sudden
impact — such as when
you hit a pothole. Keep
tires at the recommended
pressure.
Worn, old tires can cause
accidents. If the tire’s tread
is badly worn, or if your
vehicle’s tires have been
damaged, replace them.
Tire Sidewall Labeling
Useful information about a tire
is molded into the sidewall.
The following illustrations are
examples of a typical P-Metric
and a LT-Metric tire sidewall.
(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.
(B) TPC Spec (Tire
Performance Criteria
Specication)
:Original
equipment tires designed to
GM’s specic tire performance
criteria have a TPC specication
code molded onto the sidewall.
GM’s TPC specications meet
or exceed all federal safety
guidelines.
(C) DOT (Department of
Transportation)
:The
Department of Transportation
(DOT) code indicates that
the tire is in compliance
with the U.S. Department of
Transportation Motor Vehicle
Safety Standards.
Passenger (P-Metric) Tire
Service and Appearance Care 5-45

(D) Tire Identication Number
(TIN):The letters and numbers
following DOT code are the
Tire Identication Number (TIN).
The TIN shows the manufacturer
and plant code, tire size, and
date the tire was manufactured.
The TIN is molded onto both
sides of the tire, although only
one side may have the date
of manufacture.
(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 5-62.(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 see
Inflation - Tire Pressure on
page 5-51andLoading the
Vehicle on page 4-35.
(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.
(B) TPC Spec (Tire
Performance Criteria
Specication)
:Original
equipment tires designed to
GM’s specic tire performance
criteria have a TPC specication
code molded onto the sidewall.
GM’s TPC specications meet
or exceed all federal safety
guidelines.
(C) Dual Tire Maximum Load
:Maximum load that can be
carried and the maximum
pressure needed to support
that load when used in a dual
conguration. For information on
recommended tire pressure see
Inflation - Tire Pressure on
page 5-51andLoading the
Vehicle on page 4-35.
Light Truck (LT-Metric) Tire
5-46 Service and Appearance Care

(D) DOT (Department of
Transportation):The
Department of Transportation
(DOT) code indicates that
the tire is in compliance
with the U.S. Department of
Transportation Motor Vehicle
Safety Standards.
(E) Tire Identication Number
(TIN)
:The letters and numbers
following DOT code are the
Tire Identication Number (TIN).
The TIN shows the manufacturer
and plant code, tire size, and
date the tire was manufactured.
The TIN is molded onto both
sides of the tire, although
only one side may have the date
of manufacture.
(F) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(G) Single Tire Maximum Load
:Maximum load that can be
carried and the maximum
pressure needed to support that
load when used as a single.For information on recommended
tire pressure seeInflation - Tire
Pressure on page 5-51and
Loading the Vehicle on
page 4-35.
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.
Passenger (P-Metric) Tire
Light Truck (LT-Metric) Tire
Service and Appearance Care 5-47

(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.
(E) Rim Diameter
:Diameter of
the wheel in inches.
(F) Service Description
:The service description indicates
the load range and speed
rating of a tire. The load index
can range from 1 to 279. Speed
ratings range from A to Z.
Tire Terminology and
Denitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch
of the tire. Air pressure is
expressed in pounds per square
inch (psi) or kilopascal (kPa).
Accessory Weight
:This means
the combined weight of optional
accessories. Some examples
of optional accessories are,
automatic transmission, power
steering, power brakes, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire’s height to its width.
Belt
:A rubber coated layer of
cords that is located between the
plies and the tread. Cords may
be made from steel or other
reinforcing materials.Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline
of the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in pounds per
square inch (psi) or kilopascals
(kPa) before a tire has built
up heat from driving. See
Inflation - Tire Pressure on
page 5-51.
Curb Weight
:The weight of a
motor vehicle with standard
and optional equipment including
the maximum capacity of fuel,
oil, and coolant, but without
passengers and cargo.
5-48 Service and Appearance Care

Uniform Tire Quality
Grading
Quality grades can be found
where applicable on the
tire sidewall between tread
shoulder and maximum section
width. For example:
Treadwear 200 Traction AA
Temperature A
The following information relates
to the system developed by
the United States National
Highway Traffic Safety
Administration (NHTSA), which
grades tires by treadwear,
traction, and temperature
performance. This applies
only to vehicles sold in the
United States. The grades are
molded on the sidewalls of
most passenger car tires.The Uniform Tire Quality
Grading (UTQG) system
does not apply to deep tread,
winter-type snow tires,
space-saver, or temporary use
spare tires, tires with nominal rim
diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary
with respect to these grades,
they must also conform to
federal safety requirements and
additional General Motors
Tire Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a
comparative rating based on
the wear rate of the tire
when tested under controlled
conditions on a specied
government test course.For example, a tire graded
150 would wear one and a half
(1.5) times as well on the
government course as a tire
graded 100. The relative
performance of tires depends
upon the actual conditions
of their use, however, and may
depart signicantly from the
norm due to variations in
driving habits, service practices,
and differences in road
characteristics and climate.
Traction – AA, A, B, C
The traction grades, from highest
to lowest, are AA, A, B, and C.
Those grades represent the
tire’s ability to stop on wet
pavement as measured under
controlled conditions on
specied government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
5-62 Service and Appearance Care

Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts
should be replaced. If the wheel
leaks air, replace it (except some
aluminum wheels, which can
sometimes be repaired). See your
dealer/retailer if any of these
conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset, and be
mounted the same way as the one
it replaces.If you need to replace any of your
wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System
(TPMS) sensors, replace them only
with new GM original equipment
parts. This way, you will be sure
to have the right wheel, wheel bolts,
wheel nuts, and TPMS sensors
for your vehicle.
{CAUTION
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
on your vehicle can be dangerous.
It could affect the braking and
handling of your vehicle, make
your tires lose air and make you
lose control. You could have a
collision in which you or others
could be injured. Always use the
correct wheel, wheel bolts, and
wheel nuts for replacement.Notice:The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.
SeeChanging a Flat Tire on
page 5-66for more information.
Used Replacement Wheels
{CAUTION
Putting a used wheel on the
vehicle is dangerous. You cannot
know how it has been used or how
far it has been driven. It could fail
suddenly and cause a crash. If you
have to replace a wheel, use a
new GM original equipment wheel.
5-64 Service and Appearance Care