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Tire Inspection and Rotation
The tires on your vehicle should be inspected regularly
for wear. Also check for damaged tires or wheels.
SeeWhen It Is Time for New Tires on page 6-63and
Wheel Replacement on page 6-67for additional
information.
If your vehicle has P235/50R18 size tires they should
be rotated any time you notice unusual wear.
When rotating P235/50R18 size tires, always use the
correct rotation pattern shown here.
After the tires have been rotated, adjust the front and
rear in ation pressures as shown on the tire and loading
information label, seeIn ation - Tire Pressure on
page 6-58andLoading Your Vehicle on page 5-33.Vehicles that have the Tire Pressure Monitor (TPM)
system will need to have the sensors reset after a tire
rotation is performed. A special tool is needed to reset the
sensor identi cation codes. See your dealer for service.
Make certain that all wheel nuts are properly tightened.
SeeWheel Replacement on page 6-67and “Wheel Nut
Torque” underCapacities and Speci cations on
page 6-92.
{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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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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{CAUTION:
Getting under a vehicle when it is jacked up
is dangerous. If the vehicle slips off the jack,
you could be badly injured or killed. Never get
under a vehicle when it is supported only
by a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to place
the jack in the proper location before raising
the vehicle.If you ever use a jack to lift your vehicle, follow the
instructions that came with the jack, and be sure to use
the correct lifting points to avoid damaging your vehicle.
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 are using spans at least
two crossmember ribs.
Lift only in the areas shown in the following
pictures.
For additional information, see your GM dealer and
the Cadillac XLR service manual.
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1. Locate the rear lifting points (A), according to the
illustration shown.
2. Be sure to place a block or pad between the jack
and the vehicle.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 6-4.
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