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:
Changing a tire can be dangerous. The vehicle
can slip off the jack and roll over or fall on you
or other people. You and they could be badly
injured or even killed. Find a level place to
change your tire. To help prevent the vehicle
from moving:
1. Set the parking brake rmly.
2. Put the shift lever in PARK (P).
3. Turn off the engine and do not restart
while the vehicle is raised.
4. Do not allow passengers to remain in the
vehicle.
To be even more certain the vehicle will not
move, you should put blocks at the front and
rear of the tire farthest away from the one
being changed. That would be the tire, on the
other side, at the opposite end of the vehicle.When your vehicle has a at tire, use the following
example as a guide to assist you in the placement of
wheel blocks.
The following information will tell you next how to use
the jack and change a tire.
Removing the Spare Tire and Tools
The equipment you will need is located in the rear of the
vehicle. To access the equipment, do the following:
1. Remove the storage bin to access the jack if your
vehicle has the cargo management system.
If your vehicle has the third row seat, remove the
head rest storage tray to access the jack.
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2. Turn the wing nut (A) holding the jack (B) (and
storage tray, if applicable) counterclockwise and
remove it.
3. Remove the jack and wheel wrench (C).
Removing the Spare Tire
The compact spare tire is located under the vehicle,
ahead of the rear bumper. SeeCompact Spare Tire on
page 5-84for more information about the compact
spare.To remove the spare tire from the vehicle, do the
following:
A. Wheel Wrench
B. Cable
C. Retainer
D. Compact Spare Tire
1. Open the liftgate. SeePower Liftgate on page 2-12
for more information.
2. Open the storage compartment door of the cargo
management system that is nearest the liftgate
and remove the container.
3. Attach the wheel wrench (A) into the hoist shaft.
4. Turn the wheel wrench counterclockwise to
lower the spare tire to the ground. Continue turning
the wrench until the spare tire (D) can be pulled
out from under the vehicle.
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5. Tilt the retainer (C) and slip it through the wheel
opening to remove the spare tire from the cable (B).
6. Turn the wrench clockwise until you feel two slips
or hear two clicks after removing the spare tire to
raise the cable back up.
Do not store a full-size or a at road tire under the
vehicle. SeeStoring a Flat or Spare Tire and
Tools on page 5-81.
To continue changing the at tire, seeRemoving the
Flat Tire and Installing the Spare Tire on page 5-74.
If the spare tire will not lower, the secondary latch
may be engaged causing the tire not to lower.Do the following to check the cable:
1. Check under the
vehicle to see if the
cable is visible. If it is
not visible, see
Secondary Latch
System on page 5-79.
2. If it is visible, rst try to tighten the cable by turning
the wheel wrench clockwise until you hear two
clicks or feel it skip twice. You cannot over-tighten
the cable.
3. Loosen the cable then by turning the wrench
counterclockwise three or four turns.
4. Tighten the cable all the way and then loosen it at
least two times, if the spare tire has not lowered.
If the spare tire did lower to the ground, continue
with Step 4 underRemoving the Spare Tire
and Tools on page 5-71.
If you still cannot lower the spare tire to the ground, see
Secondary Latch System on page 5-79.
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