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 speci ed
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 signi cantly 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
speci ed government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
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Temperature – A, B, C
The temperature grades are
A (the highest), B, and C,
representing the tire’s resistance
to the generation of heat and
its ability to dissipate heat
when tested under controlled
conditions on a speci ed indoor
laboratory test wheel. Sustained
high temperature can cause
the material of the tire to
degenerate and reduce tire life,
and excessive temperature
can lead to sudden tire failure.
The grade C corresponds to
a level of performance which all
passenger car tires must meet
under the Federal Motor Vehicle
Safety Standard No. 109. Grades
B and A represent higher levels
of performance on the laboratory
test wheel than the minimum
required by law. It should benoted that the temperature grade
for this tire is established for a tire
that is properly in ated and not
overloaded. Excessive speed,
underin ation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
{WARNING
The temperature grade for this
tire is established for a tire
that is properly in ated and
not overloaded. Excessive
speed, underin ation, or
excessive loading, either
separately or in combination,
can cause heat buildup and
possible tire failure.
Wheel Alignment and
Tire Balance
The tires and wheels on your
vehicle were aligned and balanced
carefully at the factory to give
you the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
will not be necessary on a regular
basis. However, if you notice
unusual tire wear or your vehicle
pulling to one side or the other, the
alignment might need to be
checked. If you notice your vehicle
vibrating when driving on a
smooth road, the tires and wheels
might need to be rebalanced.
See your dealer/retailer for proper
diagnosis.
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Tire Chains
{CAUTION
Do not use tire chains. 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 the 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 the
vehicle and tire size combination
and road conditions. Follow that
manufacturer’s instructions. To
help avoid damage to the vehicle,
drive slowly, readjust or remove
the device if it is contacting the
vehicle, and do not spin the
vehicle’s wheels. If you do nd
traction devices that will t,
install them on the front tires.
Tire Changing
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. If a
jack is provided with the vehicle,
it 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. If a jack is provided
with the vehicle, only use it 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.
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Services Provided
Emergency Fuel Delivery:
Delivery of enough fuel
for the vehicle to get to the
nearest service station.
Lock-Out Service:Service is
provided to unlock the vehicle
if you are locked out. A remote
unlock may be available if you
have OnStar
®. For security
reasons, the driver must present
identi cation before this service
is given.
Emergency Tow From a Public
Road or Highway:Tow to the
nearest Saturn retailer for
warranty service, or if the vehicle
was in a crash and cannot be
driven. Assistance is also
given when the vehicle is stuck
in sand, mud, or snow.
Flat Tire Change:Service is
provided to change a at tire
with the spare tire. The spare tire,
if equipped, must be in good
condition and properly in ated.
It is the owner’s responsibility for
the repair or replacement of
the tire if it is not covered by the
warranty.
Battery Jump Start:Service is
provided to jump start a dead
battery.
Trip Interruption Bene ts and
Assistance:If your trip is
interrupted due to a warranty
failure, incidental expenses may
be reimbursed during the 5 years/
100,000 miles (160 000 km)
Powertrain warranty period.
Items considered are hotel,
meals, and rental car.
Services Not Included in
Roadside Assistance
Impound towing caused by
violation of any laws.
Legal nes.
Mounting, dismounting or
changing of snow tires, chains,
or other traction devices.
Towing or services for vehicles
driven on a non-public road or
highway.
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