Porsche 911 CARRERA - 2003 Manual page 202

Wheel alignment, wheel balancing
Also refer to "Four-Wheel d rive".
As a precaution, have wheels with summer tires
balanced in the spring, and those with mud and
snow tires before winter.
Unbalanced wheels may affect car handling and
tire life.
Only the specified weights may be used for
wheel balancing.
Self-adhesive weights must not come into con-
tact with cleaning agents, since they could drop
off.
A wheel should always be balanced after a tire
repair.
Uneven tread wear indicates wheel imbalance. In
this event, the vehicle should be checked at an
authorized Porsche dealer.
/!\. Warning!
If, during a journey, uneven running or vi-
brations occur that could be caused by
damage to tires or the car, the speed must
be reduced immediately, but without brak-
ing sharply.
If you continue your trip without having the
cause of the fault remedied, you might lose
control of your vehicle which could cause
severe personal injury.
I>
Stop the vehicle and check the tires.
202
Practical Tips, Emergency Service
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If no cause for the fault can be found, drive
carefully to the nearest authorized Porsche
dealer.
Removing and storing tires
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After changing, adjust tire pressure and
torque wheel bolts diagonally to 94 ftlb
(130
Nm).
See "Changing wheels".
Tires must always remain on the same side
of the vehicle.
When wheels are removed, the direction of rota-
tion and position of each wheel should be
marked.
Example
FR (front right), FL, RR and RL.
Wheels must always be fitted in accordance with
their marking.
The preception that tire durability and perfor-
mance are immune to the effects of storage and
age is unfounded.
Chemical additives, which make the rubber elastic,
lose their effectiveness in the course of time and
the rubber becomes brittle and cracks.
Therefore, the tires, especially the spare
tire, should be inspected from time to time.
Note
Under no circumstances should tires older than
6 years be used on your Porsche.
The age of the tire can be obtained from the
"DOT" code number. If, for example, the last
three numbers read 1202, then the tire was pro-
duced in the 12th week of 2002.
Store tires in a cool and dry place.
Snowtires
For a better grip on snow and ice, use radial M+S
tires with studs.
Check with your local Motor Vehicle Bureau for
possible restricTIons.
/!\.
Warning!
Risk of loss of control and damage to the
vehicle as well as severe personal injury.
The standard tires profile and rubber mix-
ture are optimized for wet and dry driving
conditions, and may not prove favorable for
snow conditions.
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Therefore install M+S tires before driving in
such conditions.