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Width
& aspect ratio
The "P" in front of the
number stands for
"passenger."
"215" represents the
width of the tire in millimeters.
"65" is the ratio of
height to width. The
"R" stands for
"radial" and the
"15" is the diameter of
the wheel in inches. A
"B" in place of the
"R" means the tire is
belted bias construction. A
"D" in place of the
"R" means diagonal bias
construction. |
Service
Description:
"89H" in this example,
consists of the load index (89)
and speed symbol (H). This only
appears on speed-rated tires. |
DOT
code:
The letters "DOT"
certify compliance with all
applicable safety standards
established by the Department of
Transportation (DOT). Adjacent to
this is a tire identification or
serial number. This serial number
is a code with up to 11 digits
that are a combination of numbers
and letters.
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Ply
composition:
The sidewall also shows the type
of cord and number of plies in
the sidewall and under the tread.
The DOT requires tire
manufacturers to grade passenger
car tires based on three
performance factors: treadwear,
traction and temperature
resistance. |
Treadwear,
traction & temp.:
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test track.
A tire graded 200 would wear
twice as long on the government
test course under specified test
conditions as one graded 100.
Traction grades, from highest to
lowest, are A, B and C. They
represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on
specified government test
surfaces of asphalt and concrete.
The temperature grades, from
highest to lowest, are A, B and
C. These represent the tire's
resistance to the generation of
heat when tested under controlled
conditions on a specified indoor
laboratory test wheel.
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Load
limit:
The maximum load is shown in lbs.
(pounds) and in kg (kilograms),
and maximum pressure in psi
(pounds per square inch) and in
kPa (kilopascals). Kilograms and
kilopascals are metric units of
measurement. |
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