BMW x5 2001 Manual De Usuario

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Tire replacement 
To maintain good handling and vehicle 
response, use only tires of a single 
tread configuration from a single manu-
facturer. BMW tests and approves 
wheel/tire combinations. Refer to 
page 
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.
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Treadwear
The treadwear grade is a comparative 
rating based on the wear rate of the tire 
when tested under controlled condi-
tions on a specified government 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 condi-
tions of their use, however, and may 
depart significantly from the norm due 
to variations in driving habits, service 
practices and differences in road char-
acteristics 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 speci-
fied 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, 
aquaplaning, or peak traction charac-
teristics.
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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 condi-
tions on a specified indoor laboratory 
test wheel. 
Sustained high temperature can cause 
the material of the tire to degenerate 
and reduce tire life, and excessive 
temperature can lead to a sudden flat 
tire. 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. 
The temperature grade for this tire 
is established for a tire that is 
properly inflated and not overloaded. 
Excessive speed, underinflation, or 
excessive loading, either separately or 
in combination, can cause heat buildup 
and possible a flat tire.
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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
Do not use retreaded tires, since 
driving safety may be impaired by 
their use. This is due to the possible 
variations in casing structures and, in 
some cases, to their extreme age, 
which can lead to a decrease in their 
durability.
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Online Edition for Part No. 01 41 0 155 558 - © 09/00 BMW Group