Tire Identification Marks; Uniform Tire Quality Grading; Tire Identification Number - BMW 525i Owner's Manual

Tire identification marks

Knowledge of the labeling on the side of the tire
makes it easier to identify and choose the right
tires.
Tire size
e.g. 225/50 R
Nominal width in mm
Aspect ratio in Ξ
Belted construction – radial
Rim diameter in inches
Carrying capacity ID-code
(not in ZR tires)
Speed code letter
(in ZR tires before the R)
Speed letter
Q = up to 100 mph/160 km/h
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

Tires with DOT codes meet the guidelines of
the U.S. Department of Transportation.
DOT code:
e.g. DOT xxxx xxx 0705
Manufacturer code
for tire make
Tire size and tire design
Tire age
Tire age
The manufacturing date of tires is contained in
the tire coding: DOT... 0705 indicates that the
tire was manufactured in week 7 of 2005.
BMW recommends that you replace all tires
after 6 years at most, even if some tires may last
for 10 years.
Online Edition for Part-No. 01 41 0 159 251 © 03/05 BMW AG

Uniform Tire Quality Grading

Quality grades can be found where applicable
on the tire sidewall between tread shoulder and
maximum section width. For example:
Tread wear 200 Traction AA
Temperature A
17
94 W
DOT Quality Grades
Tread wear
Traction AA A B C
Temperature A B C
to these
Tread wear
The tread wear 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 (1γ) 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 significantly from
the norm due to variations in driving habits, ser-
vice practices and differences in road charac-
teristics 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 sur-
faces of asphalt and concrete. A tire marked C
may have poor traction performance.
tests, and does not include acceleration, cor-
nering, hydroplaning, or peak traction charac-
teristics.<
All passenger car tires must conform to
Federal Safety Requirements in addition
grades.<
The traction grade assigned to this tire is
based on straight-ahead braking traction
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