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 ex‐
plains what the letters and numbers in
the wheel size designation mean. Example wheel size designation:
7.5JX19
7.5 - Rim width in inches.
J - Rim contour designation.
19 - Rim diameter in inches.
Tire speed ratings
The chart below lists many of the dif‐ ferent speed ratings currently being
used for passenger car tires. The speed
rating is part of the tire size designa‐ tion on the sidewall of the tire. This
symbol corresponds to that tire's de‐
signed maximum safe operating speed.
SpeedRatingSymbolMaximum 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)
SpeedRatingSymbolMaximum Speed
Z Above 240 km/h (149
mph)
3. Checking tire life (TIN: Tire
Identification Number)
Any tires that are over 6 years old,
based on the manufacturing date, (in‐ cluding the spare tire) should be re‐
placed 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 consist‐ ing 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 means a
plant code number, tire size and tread
pattern and the last four numbers indi‐ cate week and year manufactured.
For example:
DOT XXXX XXXX 1616 represents that
the tire was produced in the 16th week
of 2016.
WARNING
nTire age
Tires degrade over time, even whenthey are not being used.Regardless of the remaining tread,we recommend that tires be re‐placed after approximately six (6)years of normal service. Heat causedby hot climates or frequent highloading conditions can accelerate theaging process. Failure to follow thiswarning can result in sudden tirefailure, which could lead to a loss ofcontrol and an accident involving se‐rious injury or death.
4. Tire ply composition and material
The number of layers or plies of rub‐
ber-coated fabric in the tire. Tire man‐ ufacturers also must indicate the ma‐
terials 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.
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Maintenance
