tire type HUMMER H3 2007 Owners Manual

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.
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,
your 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 241
andStabiliTrak
®System on page 244.
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.
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The trailer tongue weight (A) should be 10 percent
to 15 percent of the total loaded trailer weight (B),
up to a maximum of 500 lbs (227 kg) with a weight
carrying hitch or a weight distributing hitch.
Do not exceed the maximum allowable tongue
weight for your vehicle. Choose the shortest hitch
extension that will position the hitch ball closest
to the vehicle. This will help reduce the effect
of trailer tongue weight on the rear axle.Your spare tire carrier is behind the tailgate.
If your hitch extension is too short, the spare
tire may interfere with trailer coupling or trailer
tongue jack operation on some types of trailers.
After you’ve loaded your trailer, weigh the
trailer and then the tongue, separately, to see if
the weights are proper. If they aren’t, you may be
able to get them right simply by moving some
items around in the trailer.Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the
upper limit for cold tires. You’ll nd these numbers
on the Certication/Tire Label located on the
B-pillar below the door latch or seeLoading Your
Vehicle on page 289. Then be sure you don’t
go over the GVW limit for your vehicle, or
the GAWR, including the weight of the trailer
tongue. If you use a weight distributing hitch, make
sure you don’t go over the rear axle limit before
you apply the weight distribution spring bars.
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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.
(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.
Passenger (P-Metric) Tire
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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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(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 seeInation - Tire Pressure on
page 375andLoading Your Vehicle on page 289.
(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 seeInation - Tire Pressure on
page 375andLoading Your Vehicle on page 289.
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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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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.
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If the tires have an all-season tread design, the
TPC spec number will be followed by a MS,
for mud and snow. SeeTire Sidewall Labeling on
page 368for additional information.
{CAUTION:
Mixing tires could cause you to lose
control while driving. If you mix tires of
different sizes, brands, or types (radial
and bias-belted tires) the vehicle may not
handle properly, and you could have a
crash. Using tires of different sizes,
brands, or types may also cause damage
to your vehicle. Be sure to use the correct
size, brand, and type of tires on your
vehicle’s wheels.
{CAUTION:
If you use bias-ply tires on your vehicle,
the wheel rim anges could develop
cracks after many miles of driving. A tire
and/or wheel could fail suddenly, causing
a crash. Use only radial-ply tires with the
wheels on your vehicle.
If you must replace your vehicle’s tires with those
that do not have a TPC Spec number, make
sure they are the same size, load range, speed
rating, and construction type (radial and
bias-belted tires) as your vehicle’s original tires.
384

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.
Warning:The traction grade assigned to this tire
is based on straight-ahead braking traction
tests, and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
386

Tire Chains
{CAUTION:
If your vehicle has LT285/75R16 or
P265/65R18 size tires, do not use tire
chains. They can damage your vehicle
because there is not enough clearance.
Tire chains used on a vehicle without the
proper amount of clearance can cause
damage to the brakes, suspension, or
other vehicle parts. The area damaged by
the tire chains could cause you to lose
control of your vehicle and you or others
may be injured in a crash.
Use another type of traction device only if
its manufacturer recommends it for use
on your vehicle and tire size combination
and road conditions.
CAUTION: (Continued)
CAUTION: (Continued)
Follow that manufacturer’s instructions.
To help avoid damage to your vehicle,
drive slowly, readjust, or remove the
device if it is contacting your vehicle, and
do not spin your vehicle’s wheels.
If you do nd traction devices that will t,
install them on the rear tires.
Notice:If your vehicle has a tire size other than
LT285/75R16 or P265/65R18 use tire chains only
where legal and only when you must. Use
chains that are the proper size for your tires.
Install them on the tires of the rear axle. Do not
use chains on the tires of the front axle. Tighten
them as tightly as possible with the ends
securely fastened. Drive slowly and follow the
chain manufacturer’s instructions. If you can
hear the chains contacting your vehicle, stop
and retighten them. If the contact continues,
slow down until it stops. Driving too fast or
spinning the wheels with chains on will damage
your vehicle.
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