Maintenance9-38
Tire sidewall labeling
This information identifies and
describes the fundamental
characteristics of the tire and also
provides the tire identification
number (TIN) for safety standard
certification. The TIN can be used to
identify the tire in case of a recall.
OHI078081
1. Manufacturer or brand name
Manufacturer or brand name is
shown.
2. Tire size designation
A tire’s sidewall is marked with a
tire size designation. You will need
this information when selecting
replacement tires for your car.
The following explains what the
letters and numbers in the tire size
designation mean. Example tire size designation:
(These numbers are provided as
an example only; your tire size
designator could vary depending on
your vehicle.)
235/60R18 102H
235 - Tire width in millimeters.
60 - Aspect ratio. The tire’s section
height as a percentage of its
width.
R - Tire construction code (Radial).
18 - Rim diameter in inches.
102 - Load Index, a numerical code associated with the maximum
load the tire can carry.
H - Speed Rating Symbol. See the speed rating chart in this section
for additional information.Wheel size designation
Wheels are also marked with
important information that you need
if you ever have to replace one. The
following explains what the letters
and numbers in the wheel size
designation mean.
Example wheel size designation:
7.5J X 18
7.5 - Rim width in inches.
J - Rim contour designation.
18 -
Rim diameter in inches.
09
9-41
WARNING
The temperature grade for this
tire is established for a tire that
is properly inflated and not
overloaded. Excessive speed,
under-inflation, over-inflation, or
excessive loading, either separately
or in combination, can cause heat
build-up and possible sudden
tire failure. This may cause loss
of vehicle control resulting in an
accident.
Tire Terminology and Definitions
Air Pressure
The amount of air inside the tire pressing
outward on 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 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.
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.
