BMW 2004 X3 3.0i SAV Manual Do Proprietário

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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 Vehicle Safety 
Standard No. 109. Grades B and A repre-
sent 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 load-
ing, either separately 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 
summer tires.
Tire condition
Inspect your tires frequently for treadwear, 
signs of damage and for foreign objects 
lodged in the tread. Check the tread pat-
tern depth.
Tire tread
The tread depth should not drop below 
0.12 in/3 mm, although, for example, Euro-
pean legislation 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 display a noticeable loss in 
their ability to cope with cold-weather driv-
ing conditions 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 
circumference and are marked on the tire 
sidewall with TWI – Tread Wear Indicator. 
At a tread depth of 0.063 in/1.6 mm these 
indicators, signal that the tires have 
reached the legally permissible wear limit.
Tire damage
Unusual vibrations encountered dur-
ing normal vehicle operation can indi-
cate tire failure or some other vehicle 
defect. This can, for example, be caused by 
driving over curbs. These kinds of prob-
lems may also be signaled by other 
changes in vehicle response, such as a 
strong tendency to pull to the left or right. 
Should this occur, respond by immediately 
reducing your speed. Proceed carefully to 
the nearest BMW Sports Activity Vehicle 
Center or professional tire center, or have 
the vehicle towed in to have it, its wheels 
and 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 occupants and 
other road users alike.
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Replacing wheels/tires
Unprofessional attempts by laymen to 
service tires can lead to damage and 
accidents. 
Have this work performed by skilled pro-
fessionals only. All BMW Sports Activity 
Vehicle Centers will be happy to help you 
Online Edition for Part No. 01 41 0 157 631 - © 07/03 BMW AG