BMW x3 2005 Manual Do Utilizador

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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.
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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 pattern depth.
Tire tread 
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. As winter tires dis-
play a noticeable loss in their ability to cope with 
cold-weather driving conditions once the tread 
wears to below 0.16 in/4 mm, to ensure contin-
ued 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. At a tread 
depth of 0.063 in/1.6 mm these indicators, sig-
nal that the tires have reached the legally per-
missible wear limit.
Wheel/tire damage 
Due to low-profile tires, please note that 
wheels, tires and suspension parts are 
more susceptible to road hazard and conse-
quential 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. 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. Drive carefully to the next BMW 
Sports Activity Vehicle Center or tire dealer, or 
have the vehicle towed to one of these locations 
if necessary.
Tire damage, extending to sudden and com-
plete loss of pressure in extreme cases, can 
pose a potentially lethal safety hazard for the 
vehicle's occupants and other road users 
alike.
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