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Any time you notice unusual wear, rotate your
tires as soon as possible and check wheel
alignment. Also check for damaged tires or
wheels. SeeWhen It Is Time for New Tireson
page 7!73andWheel Replacementon page 7!77.
When rotating your vehicle's tires, always use the
correct rotation pattern shown here.
Do not include the spare tire in the tire rotation.
After the tires have been rotated, adjust the front
and rear inflation pressures as shown on the Tire
and Loading Information label. SeeInflation - Tire
Pressureon page 7!65andLoading the Vehicleon
page 6!32.
Reset the Tire Pressure Monitor System. SeeTire
Pressure Monitor Operationon page 7!68.
Make certain that all wheel nuts are properly
tightened. See“Wheel Nut Torque”under
Capacities and Specificationson page 7!115.
{WARNING:
Rust or dirt on a wheel, or on the parts to
which it is fastened, can make wheel nuts
become loose after time. The wheel could
come off and cause an accident. 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 needed, to get all the rust or dirt off.
SeeChanging a Flat Tireon page 7!80.
Make sure the spare tire is stored securely.
Push, pull, and then try to rotate or turn the tire.
If it moves, tighten the cable. SeeStoring a Flat
or Spare Tire and Toolson page 7!94.
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When It Is Time for New Tires
Various factors, such as maintenance, temperatures,driving speeds, vehicle loading, and road conditions,influence when you need new tires.
One way to tell when it istime for new tires is tocheck the treadwearindicators, which appearwhen your tires have only1/16 inch (1.6 mm) or lessof tread remaining. Somecommercial truck tiresmay not have treadwearindicators.
You need new tires if any of the following statementsare true:
.You can see the indicators at three or moreplaces around the tire.
.You can see cord or fabric showing throughthe tire's rubber.
.The tread or sidewall is cracked, cut, or snaggeddeep enough to show cord or fabric.
.The tire has a bump, bulge, or split.
.The tire has a puncture, cut, or other damage thatcannot be repaired well because of the size orlocation of the damage.
The rubber in tires degrades over time, even if they arenot being used. This is also true for the spare tire,if your vehicle has one. Multiple conditions affect howfast this aging takes place, including temperatures,loading conditions, and inflation pressure maintenance.With proper care and maintenance tires will typicallywear out before they degrade due to age. If you areunsure about the need to replace your tires as they getolder, consult the tire manufacturer for more information.
Buying New Tires
GM has developed and matched specific tires for yourvehicle. The original equipment tires installed on yourvehicle, when it was new, were designed to meetGeneral Motors Tire Performance Criteria Specification(TPC spec) system rating. If you need replacementtires, GM strongly recommends that you get tires withthe same TPC Spec rating. This way, your vehicle willcontinue to have tires that are designed to give thesame performance and vehicle safety, during normaluse, as the original tires.
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GM's exclusive TPC Spec system considers over adozen critical specifications that impact the overallperformance of your vehicle, including brake systemperformance, ride and handling, traction control, and tirepressure monitoring performance. GM's TPC Specnumber is molded onto the tire's sidewall near the tiresize. If the tires have an all!season tread design, theTPC spec number will be followed by an MS for mudand snow. SeeTire Sidewall Labelingon page 7!60foradditional information.
GM recommends replacing tires in sets of four. This isbecause uniform tread depth on all tires will help keepyour vehicle performing most like it did when the tireswere new. Replacing less than a full set of tires canaffect the braking and handling performance of yourvehicle. SeeTire Inspection and Rotationon page 7!71for information on proper tire rotation.
{WARNING:
Mixing tires could cause you to lose control while
driving. If you mix tires of different sizes, brands,
or types (radial and bias-belted tires), the vehicle
might not handle properly, and you could have a
crash. Using tires of different sizes, brands,
or types could also cause damage to your vehicle.
Be sure to use the same size, brand, and type
tires on all wheels.
Your vehicle may have a different size spare than
the road tires (those originally installed on your
vehicle). When new, your vehicle included a spare
tire and wheel assembly with a similar overall
diameter as your vehicle's road tires and wheels,
so it is all right to drive on it. Because this spare
was developed for use on your vehicle, it will not
affect vehicle handling.
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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 specified
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 significantly 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 specified
government test surfaces of asphalt and concrete.
A tire marked C may have poor traction
performance.
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A. Wheel Block
B. Flat Tire
The following information explains how to use the jackand change a tire.
Removing the Spare Tire and Tools
The equipment you will need is stored under thestorage tray, which is located on the driver's side trimpanel (over the rear wheelhouse).
Regular Wheelbase shown, ExtendedWheelbase similar.
1. Remove the tray to access the tools by pulling upon the finger depression under the jack symbol.
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To access the spare tire:
A. Hoist Assembly
B. Hoist Shaft
C. Hoist Shaft AccessCover/Hole
D. Jack HandleExtensions
E. Wheel Wrench
F. Hoist Cable
G. Tire/Wheel Retainer
H. Spare Tire (ValveStem Pointed Down)
I. Hoist ShaftAccess Hole
J. Hoist End ofExtension Tool
K. Spare Tire Lock
1. To reach the hoist shaft access cover (C), you willfirst need to remove the hitch cover. Remove it byturning the two fasteners located at the bottom ofthe cover counterclockwise and then pull the coverdown and rotate towards you.
2. Open the hoist shaft access cover (C) on thebumper to access the spare tire lock (K).
3. To remove the spare tire lock insert the ignitionkey, turn it clockwise and then pull the lock out.
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4. Assemble the two jack handle extensions (D) andwheel wrench (E) as shown.
5. Insert the open end ofthe extension (J)through the hole in therear bumper (I) (hoistshaft access hole).
Be sure the hoist end (J) of the extension (D)connects to the hoist shaft (B). The ribbed squareend of the extension is used to lower the spare tire.
6. Turn the wheel wrench (E) counterclockwise tolower the spare tire (H) to the ground. Continue toturn the wheel wrench until the spare tire can bepulled out from under the vehicle.
If the spare tire does not lower to the ground, thesecondary latch is engaged causing the tire not tolower. SeeSecondary Latch Systemon page 7!91for more information.
7. Use the wheel wrenchhook that allows you topull the hoist cabletowards you, to assistin reaching thespare tire.
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8. Tilt the tire toward the vehicle with some slack inthe cable to access the tire/wheel retainer (G).Separate the retainer from the guide pin by slidingthe retainer up the pin while pressing down on thelatch.
Once the retainer is separated from the pin, tilt theretainer and pull it through the center of the wheelalong with the cable and latch.
9. Put the spare tire near the flat tire.
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