Tire replacement, Tire condition – BMW M3 Convertible 2004 User Manual

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119

Do not drive on a deflated – flat –
tire. A flat tire greatly impairs

steering and braking response, and can
lead to complete loss of control over
the vehicle.
Avoid overloading the vehicle so that
the permitted load on the tires is not
exceeded. Overloading can lead to
overheating and internal tire damage.
This can result in a sudden loss of tire
inflation pressure.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect.
This type of problem can be caused by
contact with curbs, etc. This is also true
for irregularities in the vehicle's han-
dling characteristics, such as a pro-
nounced tendency to pull to the left or
right. Should this occur, respond by
immediately reducing your speed. Pro-
ceed carefully to the nearest BMW cen-
ter or professional tire center, or have
the vehicle towed in to have it, its
wheels or its tires inspected.
Tire damage, up to and including blow-
outs, can endanger the lives of both the
vehicle occupants and other road
users.

Tire replacement

To maintain good handling characteris-
tics, only use a full set of tires of the
same brand and tread configuration.

Comply with the specified tire inflation
pressures, and be sure to have the
wheel and tire assembly balanced
every time you change a tire or wheel.

DOT quality grades

> 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.

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

– 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,
hydroplaning, or peak traction charac-
teristics.

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.

Tire condition

Overview

Controls

Maintenance

Repairs

Data

Index