BMW 2009 X3 xDrive30i Manual Do Proprietário

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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
Speed code letter
Q  = up to 105 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:
Tire age
The tire's date of manufacture is indicated on 
the sidewall:
DOT ... 3008 indicates that a tire was manufac-
tured in week 30 of the year 2008.
BMW recommends that you replace all tires 
after 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:
Tread wear 200 Traction AA 
Temperature A
DOT Quality Grades
Tread wear 
Traction AA A B C 
Temperature A B C
All passenger car tires must conform to 
Federal Safety Requirements in addition 
to these grades.
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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 (1 1/2) times as well on the govern-
ment 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 varia-
tions in driving habits, service practices and dif-
ferences in road characteristics and climate.
Traction
The traction grades, from highest to lowest, 
are AA, A, B, and C. 
These grades represent the tire's ability to stop 
on wet pavement, as measured under con-
trolled 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, cor-
nering, hydroplaning, or peak traction charac-
teristics.
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e.g.
235/50 R 18 97 V
Nominal width in mm
Cross-sectional 
relationship in 
Ξ
Radial tire code
Rim diameter in inches
Load rating, not for ZR tires
Speed rating, before R on ZR tires
e.g.
DOT xxxx xxx 3005
Manufacturer code
for tire make
Tire size and tire design
Tire age
Online Edition for Part no. 01 41 2 601 104 - © 08/08 BMW AG