2007 CHEVROLET CORVETTE width

Q:What is wrong with this?
A:The belt is twisted across the body.
{CAUTION:
You can be seriously injured by a twisted
belt. In a crash, you would not have the
full width of the belt to spread impact
forces. If a belt is twisted, make it straight
so it can work properly, or ask your
dealer/retailer to x it.
28

Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The example below shows a typical
passenger (p-metric) tire sidewall.(A) Tire Size:The tire size is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction
type, and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications 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 Identication Number (TIN):The letters
and numbers following DOT code are the Tire
Identication 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.
Passenger (P-Metric) Tire Example
380

(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 seeUniform Tire Quality
Grading on page 396.
(G) Maximum Cold Ination Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.
Tire Size
The following illustration shows an example of a
typical passenger (p-metric) 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 certied to carry.
The load index can range from 1 to 279.
The speed rating is the maximum speed a
tire is certied to carry a load. Speed ratings
range from A to Z.
381

Tire Terminology and Denitions
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.
Bias Ply Tire:A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.Cold Tire Pressure:The amount of air pressure
in a tire, measured in pounds per square inch (psi)
or kilopascals (kPa) before a tire has built up
heat from driving. SeeInation - Tire Pressure
on page 386.
Curb Weight:This means the weight of a motor
vehicle with standard and optional equipment
including the maximum capacity of fuel, oil, and
coolant, but without passengers and cargo.
DOT Markings:A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identication Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR:Gross Vehicle Weight Rating.
SeeLoading Your Vehicle on page 309.
GAWR FRT:Gross Axle Weight Rating for the
front axle. SeeLoading Your Vehicle on page 309.
GAWR RR:Gross Axle Weight Rating for the
rear axle. SeeLoading Your Vehicle on page 309.
382

Different Size Tires and Wheels
If you add wheels or tires that are a different size
than your original equipment wheels and tires,
this may affect the way your vehicle performs,
including its braking, ride and handling
characteristics, stability, and resistance to
rollover. Additionally, if your vehicle has electronic
systems such as, anti-lock brakes, traction
control, and electronic stability control, the
performance of these systems can be affected.
{CAUTION:
If you add different sized wheels, your
vehicle may not provide an acceptable
level of performance and safety if tires
not recommended for those wheels are
selected. You may increase the chance
that you will crash and suffer serious
injury. Only use GM specic wheel and
tire systems developed for your vehicle,
and have them properly installed by a
GM certied technician.SeeBuying New Tires on page 394and
Accessories and Modications on page 319
for additional information.
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.
396

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/retailer
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.
398