2007 GMC SIERRA CLASSIC tire type

(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/
transaxle, 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.
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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’re 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.
Dual Tire Operation
When the vehicle is new, or whenever a wheel,
wheel bolt or wheel nut is replaced, check the
wheel nut torque after 100, 1,000 and 6,000 miles
(160, 1 600 and 10 000 km) of driving. For proper
torque and wheel nut tightening information, see
Removing the Spare Tire and Tools on page 566.
The outer tire on a dual wheel setup generally
wears faster than the inner tire. Your tires will wear
more evenly and last longer if you rotate the
tires periodically, seeTire Inspection and Rotation
on page 553. Also seeScheduled Maintenance
(Gasoline Engine) on page 617.
{CAUTION:
If you operate your vehicle with a tire
that is badly underinated, the tire can
overheat. An overheated tire can lose air
suddenly or catch re. You or others
could be injured. Be sure all tires
(including the spare) are properly inated.
SeeInation - Tire Pressure on page 551, for
information on proper tire ination.
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{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 same
size, brand, and type tires on all wheels.
Your vehicle may have a different size
spare than the road tires (those originally
installed on your vehicle). When new, your
vehicle included a spare tire and wheel
assembly with a similar overall diameter
as your vehicle’s road tires and wheels,
so it is all right to drive on it. Because
this spare was developed for use on your
vehicle, it will not affect vehicle handling.
{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.
Your vehicle’s original equipment tires are listed
on the Tire and Loading Information Label.
This label is attached to the vehicle’s center pillar
(B-pillar). SeeLoading Your Vehicle on page 409,
for more information about the Tire and Loading
Information Label and its location on your vehicle.
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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.
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CAUTION: (Continued)
Use another type of traction device
only if its manufacturer recommends
it for use on your vehicle and tire size
combination and road conditions. 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 does not have dual
wheels and is equipped with a tire size other
than P265/75R16, LT265/75R16, P265/70R17
or P275/55R20, 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. Don’t 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.
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 will create 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.
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Spare Tire
Your vehicle, when new, had a fully-inated spare
tire. A spare tire may lose air over time, so check its
ination pressure regularly. SeeInation - Tire
Pressure on page 551andLoading Your Vehicle on
page 409for information regarding proper tire
ination and loading your vehicle. For instruction on
how to remove, install or store a spare tire, see
Removing the Flat Tire and Installing the Spare Tire
on page 571andStoring a Flat or Spare Tire and
Tools on page 584.
Notice:If your vehicle has four-wheel drive
and the different size spare tire is installed
on your vehicle, do not drive in four-wheel
drive until you can have your at tire repaired
and/or replaced. You could damage your
vehicle, and the repair costs would not be
covered by your warranty. Never use
four-wheel drive when the different size spare
tire is installed on your vehicle.Your vehicle may have a different size spare tire
than the road tires originally installed on your
vehicle. This spare tire was developed for use on
your vehicle, so it is all right to drive on it. If
your vehicle has four-wheel drive and the different
size spare tire is installed, keep the vehicle in
two-wheel drive.
After installing the spare tire on your vehicle, you
should stop as soon as possible and make
sure the spare tire is correctly inated. Have the
damaged or at road tire repaired or replaced
as soon as you can and installed back onto your
vehicle. This way, the spare tire will be available
in case you need it again.
Do not mix tires and wheels of different sizes,
because they will not t. Keep your spare tire and
its wheel together. If your vehicle has a spare
tire that does not match your vehicle’s original road
tires and wheels in size and type, do not include
the spare in the tire rotation.
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GMC and General Motors of Canada Limited
reserve the right to limit services or reimbursement
to an owner or driver when, in their sole
discretion, the claims become excessive in
frequency or type of occurrence.
Roadside Assistance is not part of or included in
the coverage provided by the New Vehicle Limited
Warranty. GMC and General Motors of Canada
reserve the right to make any changes or
discontinue the Roadside Assistance program at
any time without notication.
Towing and Road Service Exclusions
Specically excluded from Roadside Assistance
coverage are towing or services for vehicles
operated on a non-public roadway or highway,
nes, impound towing caused by a violation
of local, Municipal, State, Provincial, or Federal
law, and mounting, dismounting or changing
of snow tires, chains, or other traction devices.
Courtesy Transportation
To enhance your ownership experience, we and
our participating dealers are proud to offer
Courtesy Transportation, a customer support
program for new vehicles.
For warranty repairs during the Bumper-to-Bumper
(U.S.) or Base Warranty Coverage period
(Canada), provided by the New Vehicle Limited
Warranty, interim transportation may be available
under the Courtesy Transportation program.
Several courtesy transportation options are
available to assist in reducing your inconvenience
when warranty repairs are required.
Courtesy Transportation is not a part of the New
Vehicle Limited Warranty and is available only
at participating dealers. A separate booklet entitled
“Warranty and Owner Assistance Information”
furnished with each new vehicle provides detailed
warranty coverage information.
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