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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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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