
Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical passenger
vehicle tire and a compact spare tire sidewall.
(A) Tire Size:The tire size is a combination of letters
and numbers used to de®ne a particular tire's width,
height, aspect ratio, construction type, and service
description. See the ªTire Sizeº illustration later in this
section for more detail.(B) TPC Spec (Tire Performance Criteria
Speci®cation):Original equipment tires designed to
GM's speci®c tire performance criteria have a TPC
speci®cation code molded onto the sidewall. GM's TPC
speci®cations meet or exceed all federal safety
guidelines.
(C) DOT (Department of Transportation):The
Department of Transportation (DOT) code indicates that
the tire is in compliance with the U.S. Department of
Transportation Motor Vehicle Safety Standards.
(D) Tire Identi®cation Number (TIN):The letters and
numbers following DOT (Department of Transportation)
code is the Tire Identi®cation Number (TIN). The
TIN shows the manufacturer and plant code, tire size,
and date the tire was manufactured. The TIN is molded
onto both sides of the tire, although only one side
may have the date of manufacture.
(E) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.
(F) Uniform Tire Quality Grading (UTQG):Tire
manufacturers are required to grade tires based on three
performance factors: treadwear, traction, and
temperature resistance. For more information see
Uniform Tire Quality Grading on page 5-64.
(G) Maximum Cold In¯ation Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load. Passenger (P-Metric) Tire Example
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2006 - Pontiac GTO Owner Manual

(A) Temporary Use Only:The compact spare tire or
temporary use tire has a tread life of approximately
3,000 miles (5 000 km) and should not be driven
at speeds over 65 mph (105 km/h). The compact spare
tire is for emergency use when a regular road tire
has lost air and gone ¯at. If your vehicle has a compact
spare tire, see
Compact Spare Tire on page 5-76andIf a Tire Goes Flat on page 5-68.
(B) Tire Ply Material:The type of cord and number of
plies in the sidewall and under the tread.(C) Tire Identi®cation Number (TIN):The letters and
numbers following the DOT (Department of
Transportation) code is the Tire Identi®cation Number
(TIN). The TIN shows the manufacturer and plant code,
tire size, and date the tire was manufactured. The
TIN is molded onto both sides of the tire, although only
one side may have the date of manufacture.
(D) Maximum Cold In¯ation Load Limit:Maximum
load that can be carried and the maximum pressure
needed to support that load.
(E) Tire In¯ation:The temporary use tire or compact
spare tire should be in¯ated to 60 psi (420 kPa).
For more information on tire pressure and in¯ation see
In¯ation - Tire Pressure on page 5-58.
(F) Tire Size:A combination of letters and numbers
de®ne a tire's width, height, aspect ratio, construction
type and service description. The letter T as the
®rst character in the tire size means the tire is for
temporary use only.
(G) TPC Spec (Tire Performance Criteria
Speci®cation):Original equipment tires designed to
GM's speci®c tire performance criteria have a TPC
speci®cation code molded onto the sidewall. GM's TPC
speci®cations meet or exceed all federal safety
guidelines. Compact Spare Tire Example
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2006 - Pontiac GTO Owner Manual

Tire Size
The following illustration shows an example of a typical
passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P as the
®rst 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 60, as shown in item C of the
illustration, it would mean that the tire's sidewall is
60 percent 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 speed rating of the tire. The load
index represents the load carry capacity a tire is certi®ed
to carry. The load index can range from 1 to 279. The
speed rating is the maximum speed a tire is certi®ed
to carry a load. Speed ratings range from A to Z.
Tire Terminology and De®nitions
Air Pressure:The amount of air inside the tire pressing
outward on each square inch of the tire. Air pressure
is expressed in pounds per square inch (psi) or
kilopascal (kPa).
Accessory Weight:This means the combined weight
of optional accessories. Some examples of optional
accessories are, automatic transmission, power steering,
power brakes, power windows, power seats, and air
conditioning.
Aspect Ratio:The relationship of a tire's height to its
width.
Belt:A rubber coated layer of cords that is located
between the plies and the tread. Cords may be made
from steel or other reinforcing materials.
Bead:The tire bead contains steel wires wrapped by
steel cords that hold the tire onto the rim.
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2006 - Pontiac GTO Owner Manual

Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned
and balanced carefully at the factory to give you the
longest tire life and best overall performance.
Adjustments to wheel alignment and tire balancing will
not be necessary on a regular basis. However, if
you notice unusual tire wear or your vehicle pulling to
one side or the other, the alignment may need to
be checked. If you notice your vehicle vibrating when
driving on a smooth road, your tires and wheels
may need to be rebalanced. See your dealer for proper
diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.
{CAUTION:
Using the wrong replacement wheels, wheel
bolts, or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance, and tire or tire chain
clearance to the body and chassis.
See
Changing a Flat Tire on page 5-69for more
information.
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2006 - Pontiac GTO Owner Manual

R
Radiator Pressure Cap....................................5-26
Radios..........................................................3-44
Care of Your CD Player...............................3-57
Care of Your CDs........................................3-57
Radio with Six-Disc CD................................3-46
Setting the Time..........................................3-45
Theft-Deterrent............................................3-55
Understanding Reception..............................3-57
Rear Safety Belt Comfort Guides......................1-22
Rear Seat Passengers, Safety Belts..................1-19
Rearview Mirrors.............................................2-29
Reclining Seatbacks.......................................... 1-3
Recommended Fluids and Lubricants.................6-12
Recreational Vehicle Towing.............................4-34
Remote Keyless Entry System............................ 2-4
Remote Keyless Entry System, Operation............ 2-5
Removing the Flat Tire and Installing the
Spare Tire..................................................5-71
Removing the Spare Tire and Tools...................5-70
Replacement Bulbs.........................................5-49
Reporting Safety Defects
General Motors...........................................7-14
United States Government............................7-13
Restraint System Check
Checking the Restraint Systems....................1-53
Replacing Restraint System Parts
After a Crash..........................................1-53Retained Accessory Power (RAP)......................2-17
Right Front Passenger Position, Safety Belts......1-19
Roadside
Assistance Program....................................... 7-6
Rocking Your Vehicle to Get it Out....................4-28
Running the Engine While Parked.....................2-28
S
Safety Belt
Pretensioners..............................................1-24
Reminder Light............................................3-24
Safety Belts
Care of......................................................5-79
Driver Position............................................1-12
How to Wear Safety Belts Properly................1-11
Questions and Answers About Safety Belts.....1-11
Rear Safety Belt Comfort Guides...................1-22
Rear Seat Passengers.................................1-19
Right Front Passenger Position......................1-19
Safety Belt Use During Pregnancy.................1-19
Safety Belts Are for Everyone......................... 1-6
Shoulder Belt Height Adjuster........................1-18
Safety Warnings and Symbols.............................. iii
Scheduled Maintenance..................................... 6-4
Seatback Latches............................................. 1-5
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2006 - Pontiac GTO Owner Manual

Seats
Head Restraints............................................ 1-4
Manual Lumbar............................................. 1-2
Power Seats................................................. 1-2
Reclining Seatbacks...................................... 1-3
Seatback Latches.......................................... 1-5
Securing a Child Restraint
Rear Seat Position......................................1-41
Right Front Seat Position..............................1-43
Security Light.................................................3-31
Service........................................................... 5-3
Accessories and Modi®cations......................... 5-3
Adding Equipment to the Outside of Your
Vehicle..................................................... 5-5
California Proposition 65 Warning.................... 5-3
Doing Your Own Work................................... 5-4
Engine Soon Light.......................................3-28
Publications Ordering Information...................7-14
Servicing Your Airbag-Equipped Vehicle..............1-52
Setting the Time.............................................3-45
Sheet Metal Damage.......................................5-82
Shifting Into Park (P).......................................2-24Shifting Out of Park (P)...................................2-26
Shoulder Belt Height Adjuster...........................1-18
Signals, Turn and Lane-Change.......................... 3-8
Spare Tire
Compact....................................................5-76
Installing....................................................5-71
Removing...................................................5-70
Storing.......................................................5-75
Speci®cations, Capacities.................................5-90
Speedometer..................................................3-24
Starting Your Engine.......................................2-18
Steering........................................................4-10
Steering Wheel Controls, Audio.........................3-56
Steering Wheel, Tilt Wheel................................. 3-6
Storage Areas
Center Console Storage Area........................2-30
Cupholder(s)...............................................2-30
Front Storage Area......................................2-30
Glove Box..................................................2-30
Stuck in Sand, Mud, Ice or Snow......................4-28
Sun Visors.....................................................2-13
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2006 - Pontiac GTO Owner Manual