Tire Information
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:
195/60R15 88H
195
— Tire width in millimeters.
60
— Aspect ratio. The tire's
section height as a percentage of
its width.
R
— Tire construction code
(Radial).
15
— Rim diameter in inches.
88
— 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:
15 x 5 1/2 JJ
15
— Rim diameter in inches.
5 1/2
— Rim width in inches.
JJ
— Rim contour designation.
Tire Speed Ratings
The chart below shows many of
the different speed ratings
currently being used for
passenger car tires. The speed
rating symbol is part of the tire
size designation on the sidewall of
the tire. This symbol corresponds
to that tire's designed maximum
safe operating speed.
Technical Information
