BMW 01 41 0 155 307 Manual Do Utilizador

125

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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 

.

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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The tread wear 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 (1g) 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.

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, 
hydroplaning, or peak traction charac-
teristics.

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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 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 Stan-
dard No. 109. Grades B and A repre-
sent 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, under-inflation, or 
excessive loading, either separately or 
in combination, can cause heat buildup 
and possible tire failure.

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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

Do not use retreaded tires. Driving 
safety may be impaired by their 

use. This is due to the possible varia-
tions 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 0 155 307 - © 09/00 BMW AG