BMW 2009 X3 xDrive30i Manual Do Proprietário

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Wheels and tires
98
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 that 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.
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M+S
Winter and all-season tires.
These have better winter properties than sum-
mer 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 fall below 0.12 in/
3 mm. At tread depths below 0.12 in/3 mm, 
there is an increased risk of high-speed hydro-
planing, even when only small amounts of water 
are present on the road surface.
Winter tires display a noticeable loss in their 
ability to cope with cold-weather driving condi-
tions once the tread wears to below 0.16 in/
4 mm. To ensure continued safety you should 
always have such tires replaced.
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 worn down to the wear indicators, then the 
legally permissible tread depth limit of 0.063 in/
1.6 mm has been reached.
Wheel/tire damage
Please note that low-profile tires, make 
wheels, tires and suspension parts more 
susceptible to road hazard and consequential 
damages.
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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. The same 
applies to any other abnormal road behavior, 
such as pulling severely to the right or left.
In these cases, reduce speed immedi-
ately and have wheels and tires checked 
immediately. Drive carefully to the nearest 
BMW Sports Activity Vehicle Center or tire spe-
cialist. Have the vehicle towed to one of these 
locations if necessary.
Tire damage can pose a potentially lethal safety 
hazard for the vehicle's occupants and other 
road users alike.
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New wheels and tires
Have new wheels and tires installed only 
by your BMW Sports Activity Vehicle 
Center or a tire shop that works according to 
BMW repair procedures with correspondingly 
trained personnel. If this work is not carried out 
properly, there is a danger of subsequent dam-
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