Maintenance
9-36
Tire speed ratings
The chart below lists many of the
different 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
operating speed.
Speed Rating Symbol Maximum Speed
S 180 km/h (112 mph)
T 190 km/h (118 mph)
H 210 km/h (130 mph)
V 240 km/h (149 mph)
W 270 km/h (168 mph)
Y 300 km/h (186 mph)
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 numbers
on a tire consisting of numbers and
English letters. The manufacturing
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
numbers indicate week and year
manufactured.
For example:
DOT XXXX XXXX 1521 represents that
the tire was produced in the 15th
week of 2021. 4. Tire ply composition and material
The number of layers or plies of
rubber-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
construction; the letter “D“ means
diagonal or bias ply construction;
and the letter “B” means belted-bias
ply construction.
5. Maximum permissible inflation
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.
6. Maximum load rating
This number indicates the maximum
load in kilograms and pounds that
can be carried by the tire. When
replacing the tires on the vehicle,
always use a tire that has the same
load rating as the factory installed
tire.
7. Uniform tire quality grading
Quality grades can be found where
applicable on the tire sidewall
between tread shoulder and maximum section width.
For example:
TREADWEAR 200
TRACTION AA
TEMPERATURE A
