
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, 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
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 wheels on your vehicle were aligned and balanced
carefully at the factory to give you the longest tire life
and best overall performance.
If you notice unusual tire wear or your vehicle pulling
one way or the other, the alignment may need to
be reset. If you notice your vehicle vibrating when driving
on a smooth road, your wheels may need to be
rebalanced.
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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 if any of these conditions exist.
Your dealer 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
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
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 clearance to the
body and chassis.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your 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.
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.
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Notice:Lifting your vehicle improperly can damage
your vehicle and result in costly repairs not
covered by your warranty. To lift your vehicle
properly, follow the advice in this part.
To help prevent vehicle damage:
Be sure to place a block or pad between the
jack and the vehicle.
Make sure the jack you’re using spans at least
two crossmember ribs.
Lift only in the areas shown in the following
pictures.
For additional information, see your dealer and the
Chevrolet Corvette service manual.
Lifting From the Front
The front lifting points can be accessed from either side
of your vehicle, behind the front tires.
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3. Lift the vehicle with the jack, making sure the jack
spans at least two of the crossmember ribs (B).
For more information, seeDoing Your Own Service
Work on page 5-4.
If a Tire Goes Flat
Your Corvette has no spare tire, no tire changing
equipment and no place to store a tire.
It’s unusual for a tire to “blow out” while you’re driving,
especially if you maintain your tires properly.SeeTires on page 5-51. If air goes out of a tire, it’s
much more likely to leak out slowly.
Your vehicle has Extended Mobility Tires (EMT), so you
will not need to stop on the side of the road to change
a at tire. EMT tires can operate effectively with no
air pressure. If you drive on a de ated EMT for 25 miles
(80 km) or less and at speeds of 55 mph (90 km/h) or
less, there is a good chance that the tire can be
repaired. Contact the nearest authorized Chevrolet or
Goodyear EMT servicing facility, as soon as possible, to
have the at tire inspected and repaired or replaced.
For more information, seeExtended Mobility Tires
on page 5-56.
{CAUTION:
Special tools and procedures are required to
service an Extended Mobility Tire (EMT). If
these special tools and procedures are not
used you or others could be injured and your
vehicle could be damaged. Always be sure the
proper tools and procedures, as described in
the service manual, are used.
To order a service manual, seeService Publications
Ordering Information on page 7-11.
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Care of Safety Belts
Keep belts clean and dry.
{CAUTION:
Do not bleach or dye safety belts. If you do, it
may severely weaken them. In a crash, they
might not be able to provide adequate
protection. Clean safety belts only with mild
soap and lukewarm water.
Weatherstrips
Silicone grease on weatherstrips will make them last
longer, seal better, and not stick or squeak. Apply
silicone grease with a clean cloth. During very cold,
damp weather frequent application may be required. See
Recommended Fluids and Lubricants on page 6-12.
Washing Your Vehicle
The paint nish on the vehicle provides beauty, depth of
color, gloss retention, and durability.
The best way to preserve the vehicle’s nish is to keep it
clean by washing it often with lukewarm or cold water.Do not wash the vehicle in the direct rays of the sun.
Use a car washing soap. Do not use strong soaps
or chemical detergents. Be sure to rinse the vehicle well,
removing all soap residue completely. GM-approved
cleaning products can be obtained from your dealer. See
Vehicle Care/Appearance Materials on page 5-83.Do
not use cleaning agents that are petroleum based,
or that contain acid or abrasives. All cleaning agents
should be ushed promptly and not allowed to dry on the
surface, or they could stain. Dry the nish with a soft,
clean chamois or an all-cotton towel to avoid surface
scratches and water spotting.
Notice:If you drive your vehicle through an
automatic car wash that does not have enough
clearance for the wide rear tires and wheels, you
could damage your vehicle. Verify with the manager
of the car wash that your vehicle will t before
entering the car wash or use a touchless car wash.
High pressure car washes may cause water to enter
the vehicle.
If you are cleaning your vehicle with the hood open,
take care not to spray water directly into either end of
the air cleaner/ lter housing as this could damage
your vehicle’s engine. SeeEngine Air Cleaner/Filter on
page 5-18for more information.
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Aluminum Wheels
Notice:If you use strong soaps, chemicals,
abrasive polishes, cleaners, brushes, or cleaners
that contain acid on aluminum or chrome-plated
wheels, you could damage the surface of the
wheel(s). The repairs would not be covered by your
warranty. Use only GM-approved cleaners on
aluminum or chrome-plated wheels.
Keep the wheels clean using a soft clean cloth with mild
soap and water. Rinse with clean water. After rinsing
thoroughly, dry with a soft clean towel. A wax may then
be applied.
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.
The surface of these wheels is similar to the painted
surface of the vehicle. Do not use strong soaps,
chemicals, abrasive polishes, abrasive cleaners,
cleaners with acid, or abrasive cleaning brushes on
them because the surface could be damaged. Do not
use chrome polish on aluminum wheels.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 the 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.
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