BMW serie 3 sedan 2000 Manual Do Utilizador

114

n

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 con-
form to Federal Safety Require-

ments in addition to these grades.

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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 1/2) 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 as-
phalt 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, hy-
droplaning, or peak traction character-
istics.

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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 tem-
perature can lead to sudden tire failure. 
The grade C correspods 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 ex-
cessive loading, either separately or in 
combination, can cause heat buildup 
and possible tire failure.

<

Quality grades can be found where ap-
plicable on the tire sidewall between 
tread shoulder and maximum section 
width. For example:

Treadwear 200 Traction AA 
Temperature A

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