Tire condition, New wheels and tires – BMW M6 Convertible 2009 User Manual

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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 conditions
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 Vehi-
cle 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 sep-
arately or in combination, can cause heat
buildup and possible tire failure.

M+S

Winter and all-season tires.
These have better winter properties than sum-
mer tires.

Indicates specially reinforced tires.

Tire condition

Inspect your tires frequently for tread wear,
signs of damage and for foreign objects lodged
in the tread. Check the tread depth.

Minimum tread depth

The tread depth should not drop below 0.12 in/
3 mm, although, for example, European legisla-
tion only specifies a minimum tread depth of
0.063 in/1.6 mm. At tread depths below 0.12 in/
3 mm, there is an increased risk of high-speed
hydroplaning, even when only small amounts of
water are present on the road surface.
Winter tires noticeably loose their suitability for
winter use below a tread depth of 0.16 in/4 mm.

For the sake of safety, new tires should be
installed.

Wear indicators at the tread-groove base, refer
to arrow, are distributed over the tire's circum-
ference and are marked on the side of the tire
with TWI – Tread Wear Indicator. If the tire tread
has been driven down to the wear indicators, a
tread depth of 0.063 in/1.6 mm has been
reached.

Wheel/tire damage

Please note that low-profile tires cause wheels,
tires and suspension parts to be more suscep-
tible to road hazards and consequential dam-
ages.
Unusual vibrations encountered during normal
vehicle operation can indicate tire failure or
some other vehicle defect. This can, for exam-
ple, be caused by driving over curbs. These
kinds of problems may also be signaled by other
changes in vehicle response, such as a strong
tendency to pull to the left or right.

In these cases, reduce speed immedi-
ately and have wheels and tires thor-

oughly checked. To do so, drive carefully to the
nearest BMW center or tire shop that works
according to BMW repair procedures with cor-
respondingly trained personnel. If necessary,
have the vehicle towed there. Otherwise, tire
damage can be extremely dangerous to vehicle
occupants and other road users.

New wheels and tires

Only have new wheels and tires mounted
by a BMW center or a repair shop that

works in accordance with BMW guidelines and

This manual is related to the following products:

M6 Coupe 2009