BMW X5 3.0i SAV 2005 - Manual (Page 144)

144 n Tire identification marks Wheel/tire condition
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, hydro-
planing, or peak traction characteris-
tics.
<
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.
Sustained high temperature can cause
the material of the tire to degenerate
and reduce tire life, and excessive tem-
perature can lead to a sudden flat tire.
The grade C corresponds 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
excessive loading, either separately or
in combination, can cause heat buildup
and possible a tire failure.
<
M+S
Winter and all-season tires.
These have better winter properties
than summer tires.
Wheel/tire damage
Inspect your wheels and tires frequently
for tread wear, signs of damage and for
foreign objects lodged in the tread.
Check the tread pattern depth.
Please note that low-profile tires
make your wheels, tires and sus-
pension parts more susceptible to road
hazard and consequential damages.
Unusual vibrations encountered during
normal vehicle operation can indicate
tire failure or some other vehicle defect.
This can, for example, be caused by
driving over curbs. This is also true for
irregularities in the vehicle's handling
characteristics, such as a pronounced
tendency to pull to the left or right.
Should this occur, respond by immedi-
ately reducing your speed. Carefully
proceed – or have your vehicle towed –
to the nearest BMW Sports Activity
Vehicle center or tire dealer to have the
wheels or tires inspected.
Tire damage, extending to sudden and
complete loss of pressure in extreme
cases, can pose a potentially lethal
safety hazard for the vehicle's occu-
pants and other road users alike.
<
Online Edition for Part No. 01 41 0 158 701 - © 10/04 BMW AG