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Maintenance
Tire speed ratings
The chart below lists many of the dif-
ferent speed ratings currently being
used for passenger vehicle tires.The
speed rating is part of the tire size
designation on the sidewall of the
tire. This symbol corresponds to that
tire’s designed maximum safe oper-
ating speed.
3. Checking tire life (TIN :Tire
Identification Number)
Any tires that are over six years old,
based on the manufacturing date,
(including the spare tire) should be
replaced by new ones. You can find
the manufacturing date on the tire
sidewall (possibly on the inside of the
wheel), displaying the DOT Code.
The DOT Code is a series of num-
bers on a tire consisting of numbers
and English letters. The manufactur-
ing date is designated by the last four
digits (characters) of the DOT code.
DOT : XXXX XXXX OOOO
The front part of the DOT shows a
plant code number, tire size and
tread pattern and the last four num-
bers indicate week and year manu-
factured.
For example:
DOT XXXX XXXX 1420 represents
that the tire was produced in the 14th
week of 2020.
4.Tire ply composition and
material
The number of layers or plies of rub-
ber-coated fabric in the tire. Tire
manufacturers also must indicate the
materials in the tire, which include
steel, nylon, polyester, and others.
The letter "R" means radial ply con-
struction; the letter "D" means diago-
nal or bias ply construction; and the
letter "B" means belted-bias ply con-
struction.
5. Maximum permissible infla-
tion pressure
This number is the greatest amount
of air pressure that should be put in
the tire. Do not exceed the maximum
permissible inflation pressure. Refer
to the Tire and Loading Information
label for recommended inflation
pressure.
Speed
Rating
Symbol
Maximum Speed
S 112 mph (180 km/h)
T 118 mph (190 km/h)
H 130 mph (210 km/h)
V 149 mph (240 km/h)
W 168 mph (270 km/h)
Y 186 mph (300 km/h)
