Tire Size
The following illustration shows an example of a typical
passenger car tire size.
(A) P-Metric Tire:The United States version of a
metric tire sizing system. The letter “P” as the
first character in the tire size means a passenger
vehicle tire engineered to standards set by the U. S.
Tire and Rim Association.(B) Tire Width:The three-digit number indicates the
tire section width in millimeters from sidewall to sidewall.
(C) Aspect Ratio:A two-digit number that indicates
the tire height-to-width measurements. For example, if
the tire size aspect ratio is “70,” as shown in item “C” of
the illustration, it would mean that the tire’s sidewall is
70% as high as it is wide.
(D) Construction Code:A letter code is used to
indicate the type of ply construction in the tire. The letter
“R” means radial ply construction; the letter “D” means
diagonal or bias ply construction; and the letter “B”
means belted-bias ply construction.
(E) Rim Diameter:Diameter of the wheel in inches.
(F) Service Description:These characters represent
the load range and the speed rating of a tire. The
load range represents the load carrying capacity a tire is
certified to carry. The load index can range from 1 to
279. The speed rating is the maximum speed a tire
is certified to carry a load. Speed ratings range from “A”
to “Z”.
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{CAUTION:
Mixing tires could cause you to lose control
while driving. If you mix tires of different sizes
or types (radial and bias-belted tires), the
vehicle may not handle properly, and you
could have a crash. Using tires of different
sizes may also cause damage to your vehicle.
Be sure to use the same size and type tires on
all wheels. It’s all right to drive with your
compact spare temporarily, it was developed
for use on your vehicle. See “Compact Spare
Tire” in the index.
{CAUTION:
If you use bias-ply tires on your vehicle, the
wheel rim anges could develop cracks after
many miles of driving. A tire and/or wheel
could fail suddenly, causing a crash. Use only
radial-ply tires with the wheels on your vehicle.
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.
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Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used
or how far it’s 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
Notice:Use tire chains only where legal and only
when you must. Use only SAE Class “S” type chains
that are the proper size for your tires. Install them
on the front tires and tighten them as tightly as
possible with the ends securely fastened. Drive
slowly and follow the chain manufacturer’s
instructions. If you can hear the chains contacting
your vehicle, stop and retighten them. If the contact
continues, slow down until it stops. Driving too
fast or spinning the wheels with chains on will
damage your vehicle.
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Compact Spare Tire
Although the compact spare tire was fully inflated when
your vehicle was new, it can lose air after a time.
Check the inflation pressure regularly. It should be
60 psi (420 kPa).
After installing the compact spare on your vehicle, you
should stop as soon as possible and make sure
your spare tire is correctly inflated. The compact spare
is made to perform well at speeds up to 65 mph
(105 km/h) for distances up to 3,000 miles (5 000 km),
so you can finish your trip and have your full-size
tire repaired or replaced where you want. Of course, it’s
best to replace your spare with a full-size tire as
soon as you can. Your spare will last longer and be in
good shape in case you need it again.Notice:When the compact spare is installed, don’t
take your vehicle through an automatic car wash
with guide rails. The compact spare can get caught
on the rails. That can damage the tire and wheel,
and maybe other parts of your vehicle.
Don’t use your compact spare on other vehicles.
And don’t mix your compact spare tire or wheel with
other wheels or tires. They won’t fit. Keep your spare tire
and its wheel together.
Notice:Tire chains won’t t your compact spare.
Using them can damage your vehicle and can
damage the chains too. Don’t use tire chains on
your compact spare.
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Tire Inflation Check.........................................6-16
Tire Sidewall Labeling......................................5-52
Tire Size.......................................................5-56
Tire Terminology and Definitions........................5-57
Tires.............................................................5-52
Buying New Tires........................................5-62
Chains.......................................................5-66
Changing a Flat Tire....................................5-68
Compact Spare Tire.....................................5-79
If a Tire Goes Flat.......................................5-67
Inflation - Tire Pressure................................5-59
Inspection and Rotation................................5-60
Uniform Tire Quality Grading.........................5-63
Wheel Alignment and Tire Balance.................5-65
Wheel Replacement.....................................5-65
When It Is Time for New Tires......................5-62
To Use the Engine Coolant Heater....................2-19
Top Strap......................................................1-43
Top Strap Anchor Location...............................1-45
Torque Lock...................................................2-25
Total Weight on Your Vehicle’s Tires..................4-41
Towing
Recreational Vehicle.....................................4-30
Towing a Trailer..........................................4-38
Your Vehicle...............................................4-29
Trailer Brakes.................................................4-41
Transaxle
Fluid, Automatic...........................................5-19
Transaxle Operation, Automatic.........................2-20Transmission, Transaxle, Transfer Case Unit
Repair Manual............................................7-12
Transportation Options...................................... 7-8
Trap-Resistant Trunk Kit...................................2-13
Trip Odometer................................................3-24
Trunk............................................................2-11
Trunk Lamp...................................................3-15
Turn and Lane-Change Signals.......................... 3-6
Turn Signal/Multifunction Lever........................... 3-6
Turn Signals When Towing a Trailer..................4-43
U
Underbody Flushing Service.............................6-19
Understanding Radio Reception........................3-54
Uniform Tire Quality Grading............................5-63
United States – Customer Assistance.................. 7-4
Used Replacement Wheels..............................5-66
Using Cleaner on Fabric..................................5-81
Using RDS....................................................3-46
VVehicle
Control........................................................ 4-5
Damage Warnings........................................... iv
Loading......................................................4-32
Service Soon Light......................................3-35
Symbols......................................................... iv
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