BMW Z4 sDrive28i, Руководство пользователя

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Tire Identification Number
Tires with DOT codes meet the guidelines of the
U.S. Department of Transportation.
DOT code:
DOT xxxx xxx 3311
xxxx: manufacturer code for the tire brand
xxx: tire size and tire design
3311: tire age
Tire age
The tire manufacturing date is contained in the
tire identification mark: DOT ... 3311 means that
the tire was manufactured in the week 33 of
2011.
BMW recommends that you replace all tires af‐
ter 6 years at most, even if some tires may last
for 10 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
Federal Safety Requirements in addition
to these grades.◀
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 (11/2) 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, 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 surfa‐
ces 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, hydro‐
planing, 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. Sus‐
tained high temperature can cause the material
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 B and A represent
higher levels of performance on the laboratory
test wheel than the minimum required by law.
Temperature grade for this tire
The temperature grade for this tire is es‐
tablished for a tire that is properly inflated and
not overloaded. Excessive speed, underinfla‐
tion, or excessive loading, either separately or in
combination, can cause heat buildup and pos‐
sible tire failure.◀
Seite 159
Wheels and tires Mobility
159
Online Edition for Part no. 01 40 2 609 184 - 09 11 500