BMW Z8, Owner'S Manual, Page: 100 / 175

100 n
of 0.063 in/1.6 mm, the indicators will
signal that the legally permissible wear
limit has been reached.
Avoid overloading the vehicle so
that the permitted load on the tires
is not exceeded. Overloading can lead
to overheating and increases the rate at
which damage develops inside the
tires.
You could have a blowout as a result.
Unusual vibrations during driving
caused, for example, by running over
curbs etc., can indicate wheel or tire
damage, as well as other damage on
the vehicle. This also applies to abnor-
malities with regard to the accustomed
handling characteristics, such as strong
pulling to the left or right. Should this
occur, respond by immediately
reducing your speed. Proceed carefully
to the nearest BMW center or profes-
sional tire center, or have the vehicle
towed in to have it and its wheels or
tires inspected.
Tire damage can endanger the lives of
both the vehicle occupants and other
road users.
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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 and tire combinations, refer to
page
104 .
DOT Quality Grades
Tread wear
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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Tread wear
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 – 1 1/2 – times
as well on the government course as a
tire graded 100. The relative perfor-
mance of tires depends upon the actual
conditions of their use, however, and
may depart significantly from the norm
due to variations in driving habits, ser-
vice 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 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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Tire condition Tire replacement
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