Manual: 2011/2012 911

Page: 208

Tire replacements
If in doubt, contact your Porsche dealer. Use only tire makes and types approved 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.

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 noticeable change in handling occurs due to the different tread depth of the other tires.

This happens especially if only rear tires are replaced. However, this condition disappears as the new tires are broken in.

  • Please adjust your driving style accordingly.

Installation of new tires should only be done by a qualified tire technician.

Valves
Rubber valve stems must be replaced every time a tire is replaced.

For metal valves, the installation and replacement instructions must be observed.

  • Use only genuine Porsche metal valves.
  • Protect the valve inserts against soiling with valve caps.
    Soiled valve inserts can cause a gradual loss of air.
  • Use only plastic valve caps.

Parking at the curb

Curb Impact / Tire Damage

Hard impacts against curbs (or traffic islands) are dangerous and may cause hidden tire damage which is not noticeable until later. Such damage can result in accidents at high speeds.

Depending on the force of impact, the edge of the rim can also be damaged.

  • If you are in doubt, have the wheel checked by an expert, particularly if you suspect damage on the inside.
  • If you must drive over a curb or other obstacle, drive slowly and at an obtuse angle. Exercise care when parking along curbs.

Wheel alignment, wheel balancing
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 contact with cleaning agents, since they could drop off.

Uneven tread wear indicates wheel imbalance. In this event, the vehicle should be checked at an authorized Porsche dealer.

High-Speed tire Vibration

If, during a trip, uneven running or vibrations occur that could be caused by damage to tires or the car, the speed must be reduced immediately, but without braking sharply.

If you continue your trip without having the cause of the fault remedied, you might lose control of your vehicle.

  • Stop the vehicle and check the tires.
  • If no cause for the fault can be found, drive carefully to the nearest authorized Porsche dealer.