Tire Designations; Tire Terminology And Definitions - Chevrolet BOLT EV2017 Owner's Manual

Chevrolet Bolt EV Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
10122739) - 2017 - CRC - 10/3/16
resistance. For more information
see Uniform Tire Quality
Grading 0 285.
(7) Maximum Cold Inflation
Load Limit Maximum load that
:
can be carried and the
maximum pressure needed to
support that load.

Tire Designations

Tire Size
The following is an example of a
typical passenger vehicle
tire size.
(1) Passenger (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.
(2) Tire Width
:
number indicates the tire section
width in millimeters from
sidewall to sidewall.
(3) Aspect Ratio
number that indicates the tire
height-to-width measurements.
For example, if the tire size
aspect ratio is 60, as shown in
item 3 of the illustration, it would
mean that the tire's sidewall is
60 percent as high as it is wide.
(4) Construction Code
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.
(5) Rim Diameter
the wheel in inches.
(6) Service Description
characters represent the load
index and speed rating of the
tire. The load index represents
The three-digit
the load carrying capacity a tire
is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
A two-digit
:
Tire Terminology and
Definitions
Air Pressure
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in kPa (kilopascal)
A letter
:
or psi (pounds per square inch).
Accessory Weight
combined weight of optional
accessories. Some examples of
optional accessories are, electric
drive unit, power windows,
power seats, and air
conditioning.
Aspect Ratio
Diameter of
:
of a tire's height to its width.
Vehicle Care 273
These
:
The amount of
:
The
:
The relationship
: