Tire Identification Number; Tire Age; Uniform Tire Quality Grading; Dot Quality Grades - BMW X3 2013 Owner's Manual

Mobility
96: load rating, not for ZR tires
Y: speed rating, before the R on ZR tires
Speed letter
T = up to 118 mph, 190 km/h
H = up to 131 mph, 210 km/h
V = up to 150 mph, 240 km/h
W = up to 167 mph, 270 km/h
Y = up to 186 mph, 300 km/h

Tire Identification Number

DOT code: DOT xxxx xxx 1013
xxxx: manufacturer code for the tire brand
xxx: tire size and tire design

1013: tire age

Tires with DOT codes meet the guidelines of
the U.S. Department of Transportation.
Tire age
DOT ... 1013: the tire was manufactured in the
10th week 2013.
Recommendation
Regardless of wear, replace tires at least every
6 years.

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

DOT Quality Grades

Treadwear
Traction AA A B C
Temperature A B C
All passenger car tires must conform to Fed‐
eral Safety Requirements in addition to these
grades.
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Wheels and tires
Online Edition for Part no. 01 40 2 926 047 - XI/13
Online Edition for Part no. 01 40 2 911 041 - VI/13
Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested
under controlled conditions on a specified gov‐
ernment test course. For example, a tire
graded 150 would wear one and one-half, 1 g,
times as well on the government course as a
tire graded 100. The relative performance of
tires depends upon the actual conditions of
their use, however, and may depart signifi‐
cantly from the norm due to variations in driv‐
ing habits, service practices and differences in
road characteristics and climate.
Traction
The traction grades, from highest to lowest,
are AA, A, B, and C.
Those grades represent the tire's ability to
stop on wet pavement as measured under
controlled conditions on specified government
test surfaces of asphalt and concrete. A tire
marked C may have poor traction performance.
The traction grade assigned to this tire is
based on straight-ahead braking traction tests,
and does not include acceleration, cornering,
hydroplaning, or peak traction characteristics.
Temperature
The temperature grades are A, the highest, B,
and C, representing the tire's resistance to the
generation of heat and its ability to dissipate
heat when tested under controlled conditions
on a specified indoor laboratory test wheel.
Sustained high temperature can cause the ma‐
terial of the tire to degenerate and reduce tire
life, and excessive temperature can lead to
sudden tire failure. The grade C corresponds
to a level of performance which all passenger
car tires must meet under the Federal Motor
Vehicle Safety Standard No. 109. Grades Band
A represent higher levels of performance on
the laboratory test wheel than the minimum re‐
quired by law.