Porsche CARRERA GT-2004 Manual page 149

Wheel and tire damage, puncture
f Repair damage to the wheel surface (e.g.
scratches, stone damage) immediately so
that corrosion does not form.
f Replace damaged wheels with original wheels.
f Check tires for imbedded material, cuts, punc-
tures, cracks and bulges (side wall) before driv-
ing off.
In case of tire damage, where it is uncertain wheth-
er there is a break in the ply with all its conse-
quences or tire damage caused by thermal or me-
chanical overloading due to loss of pressure or
any other prior damage, we recommend that the
tire be replaced for safety reasons.
If one faulty tire is replaced it should be noted that
the difference in tread depth on one axle must not
exceed 30 %.
Handling inconsistencies may result.
f Perform a visual inspection if necessary.
Tire replacements
If in doubt, contact your Porsche dealer or
Porsche Importer of your country.
Use only tire makes and types tested by Porsche.
If you do not use a Porsche recommended
replacement tire, make sure that you
purchase your new tires from a reputable tire
dealer and that the dealer complies with all
manufacturers warnings for those tires.
Only tires with the same make and with the
same specification code (e.g. "N0", "N1"...)
can be mounted.
The tires of the Carrera GT are specially
adjusted to the characteristics of the vehicle
and guarantee optimum driving behavior.
Any tires other than those approved by
Porsche can impair the driving behavior and
safety.
Before mounting new tires, check with your
Porsche dealer about the current release
status.
Use tires with "ZR" quality standards. There
are currently no standards concerning tire
strength at speeds above 150 mph (240 km/h).
Tires should be replaced no less than on one axle
at the time.
Only tires of the same make and type must be
used. Mixed tires are not permissible.
Initially, new tires do not have their full traction.
You should therefore drive at moderate speeds
during the first 60 - 120 miles (100 - 200 km).
If new tires are installed only on one axle, a notice-
able change in handling occurs due to the different
tread depth of the other tires.
This happens especially if only rear tires are re-
placed. However, this condition disappears as the
new tires are broken in.
f Please adjust your driving style accordingly.
Installation of new tires should only be done by a
qualified tire technician.
Valves
Observe the installation and replacement instruc-
tions for metal valves.
Use only genuine Porsche metal valves.
f Protect the valve inserts against soiling with
valve caps.
Soiled valve inserts can cause a gradual loss
of air.
Parking at the curb
Warning!
Hard impacts against curbs (or traffic
islands) are dangerous and may cause hid-
den tire damage which is not noticeable until
later. Such damage can result in accidents at
high speeds causing severe personal injury.
Depending on the force of impact, the edge
of the rim can also be damaged.
f If you are in doubt, have the wheel checked by
an expert, particularly if you suspect damage
on the inside.
f If you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle. Exercise
care when parking along curbs.
Practical Tips, Emergency Service
149