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TIRE SAFETY INFORMATION
Letter Rating Speed Rating
Q 99 MPH
R 106 MPH
S 112 MPH
T 118 MPH
U 124 MPH
H 130 MPH
V 149 MPH
W 168* MPH
Y 186* MPH
U.S. DOT TIRE IDENTIFICATION NUMBER
This begins with the letters “DOT” and indicates that the tire meets all federal standards. The
next two numbers or letters are the plant code where it was manufactured, and the last four
numbers represent the week and year the tire was built. For example, the numbers 3197 means
the 31st week of 1997. The other numbers are marketing codes used at the manufacturer’s
discretion. This information is used to contact consumers if a tire defect requires a recall.
TIRE PLY COMPOSITION AND MATERIALS USED
The number of plies indicates the number of layers of rubber-coated fabric in the tire. In general,
the greater the number of plies, the more weight a tire can support. Tire manufacturers also
must indicate the materials in the tire, which include steel, nylon, polyester, and others.
MAXIMUM LOAD RATING
This number indicates the maximum load in kilograms and pounds that can be carried by the
tire.
MAXIMUM PERMISSIBLE INFLATION PRESSURE
This number is the greatest amount of air pressure that should ever be put in the tire under
normal driving conditions.
3.5.1.2 UTQGS INFORMATION
Tread wear Number
This number indicates the tire’s wear rate. The higher the tread wear number is, the longer it
should take for the tread to wear down. For example, a tire graded 400 should last twice as long
as a tire graded 200.
Traction Letter
This letter indicates a tire’s ability to stop on wet pavement. A higher graded tire should allow
you to stop your car on wet roads in a shorter distance than a tire with a lower grade. Traction is
graded from highest to lowest as “AA”,”A”, “B”, and “C”.
Temperature Letter
separately or in combination, can cause heat build-up and possible tire failure. From highest to
lowest, a tire’s resistance to heat is