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.
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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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.
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 may need to be checked. If you notice
your vehicle vibrating when driving on a smooth
road, your tires and wheels may need to be
rebalanced. See your retailer for proper diagnosis.
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
retailer if any of these conditions exist.
Your retailer will know the kind of wheel you need.
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Each new wheel should have the same
load-carrying capacity, diameter, width, offset and
be mounted the same way as the one it replaces.
{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.
If you need to replace any of your wheels, wheel
bolts, or wheel nuts, replace them only with
new Saturn original equipment parts. This way,
you will be sure to have the right wheel, wheel
bolts, and wheel nuts for your vehicle.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 clearance to the body
and chassis.{CAUTION:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after a time. The wheel
could come off and cause a crash. When
you change a wheel, remove any rust or
dirt from places where the wheel attaches
to the vehicle. In an emergency, you can
use a cloth or a paper towel to do this;
but be sure to use a scraper or wire brush
later, if you need to, to get all the rust or
dirt off.
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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
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. Follow that manufacturer’s
instructions. To help avoid damage to
your vehicle, drive slowly, re-adjust or
remove the device if it is contacting your
vehicle, and do not spin your wheels.
If you do nd traction devices that will t,
install them on the rear tires.
If a Tire Goes Flat
Your vehicle has a tire in ator kit. There is no
spare tire, no tire changing equipment, and
no place to store a tire.
It is unusual for a tire to blow out while you are
driving, especially if you maintain your tires
properly. SeeTires on page 284. If air goes out
of a tire, it is much more likely to leak out slowly.
But, if you should ever have a blow out, 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.
A rear blow out, particularly on a curve, acts much
like a skid and may require the same correction
you would use in a skid. In any rear blow out,
remove your foot from the accelerator pedal.
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The surface of these wheels is similar to the
painted surface of your vehicle. Do not use strong
soaps, chemicals, abrasive polishes, abrasive
cleaners, cleaners with acid, or abrasive cleaning
brushes on them because you could damage
the surface. Do not use chrome polish on
aluminum wheels.
Notice:Using chrome polish on aluminum
wheels could damage the wheels. The repairs
would not be covered by your warranty.
Use chrome polish on chrome wheels only.
Use chrome polish only on chrome-plated wheels,
but avoid any painted surface of the wheel, and
buff off immediately after application.
Notice:If you drive your vehicle through an
automatic car wash that has silicone carbide
tire cleaning brushes, you could damage
the aluminum or chrome-plated wheels.
The repairs would not be covered by your
warranty. Never drive a vehicle equipped with
aluminum or chrome-plated wheels through
an automatic car wash that uses silicone
carbide tire cleaning brushes.Do not take your vehicle through an automatic
car wash that has silicone carbide tire cleaning
brushes. These brushes can also damage
the surface of these wheels.
Tires
To clean the tires, use a stiff brush with tire
cleaner.
Notice:Using petroleum-based tire dressing
products on your vehicle may damage the
paint nish and/or tires. When applying a tire
dressing, always wipe off any overspray
from all painted surfaces on your vehicle.
Sheet Metal Damage
If the vehicle is damaged and requires sheet
metal repair or replacement, make sure the body
repair shop applies anti-corrosion material to
parts repaired or replaced to restore corrosion
protection.
Original manufacturer replacement parts will
provide the corrosion protection while maintaining
the warranty.
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