BMW 2004 745i Sedan Manual Do Proprietário

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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 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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Run-flat tires
You will recognize run-flat tires by a circular 
symbol containing the letters RSC on the 
side of the tire, refer to page 
.
M+S
Winter and all-season tires.
These have better winter properties than 
summer 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. 
Tire tread 
The tread depth should not fall below e in/
3 mm. 
At tread depths below e in/3 mm, there is 
an increased risk of high-speed hydroplan-
ing, 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 k/K 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 side 
of the tire with TWI – Tread Wear Indicator. 
These indicators signal at a tread depth 
of k/FK in/1.6 mm that the legally permitted 
wear limit has been reached. 
Tire damage 
Unusual vibrations encountered dur-
ing normal vehicle operation can 
indicate tire failure or some other vehicle 
defect. This can, for example, 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. Should this occur, 
respond by immediately reducing your 
speed. Carefully proceed – or have your 
vehicle towed – to the nearest BMW 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 occupants and 
other road users alike.
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Online Edition for Part No. 01 41 0 157 670 - © 08/03 BMW AG