735
Maintenance
Tyre speed ratings
The chart below lists many of the dif-
ferent speed ratings currently being
used for passenger car tyres. The
speed rating is part of the tyre size
designation on the sidewall of the
tyre. This symbol corresponds to that
tyre's designed maximum safe oper-
ating speed.
3. Checking tyre life (TIN : Tyre
Identification Number)
Any tyres that are over 6 years old,
based on the manufacturing date,
(including the spare tyre) should be
replaced by new ones. You can find
the manufacturing date on the tyre
sidewall (possibly on the inside of the
wheel), displaying the DOT Code.
The DOT Code is a series of num-
bers on a tyre 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 means a
plant code number, tyre size and
tread pattern and the last four num-
bers indicate week and year manu-
factured.
For example:
DOT XXXX XXXX 1610 represents
that the tyre was produced in the
16th week of 2010.
4. Tyre ply composition and material
The number of layers or plies of rub-
ber-coated fabric in the tyre. Tyre
manufacturers also must indicate the
materials in the tyre, 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.
S 112 mph (180 km/h)
T 118 mph (190 km/h)
H 130 mph (210 km/h)
V 149 mph (240 km/h)
Z Above 149 mph (240 km/h)
W*168 mph (270 km/h)
Maximum Speed Speed
Rating
Symbol
WARNING - Tyre age
Tyres degrade over time, even
when they are not being used.
Regardless of the remaining
tread, it is recommended that
tyres generally be replaced
after six (6) years of normal
service. Heat caused by hot cli-
mates or frequent high loading
conditions can accelerate the
aging process. Failure to follow
this warning could cause sud-
den tyre failure, which could
lead to a loss of control and an
accident involving serious
injury or death.
* W speed rating is sub-category of the Z
speed rating.
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