Manual: 2011/2012 911

Page: 207

Tire wear
The original equipment tires on your Porsche have built-in tire wear indicators. They are molded into the bottom of the tread grooves and will appear as approximately 1/2 in. (12 mm) bands when the tire tread depth is down to 1/16 of an in. (1.6 mm).

When the indicators appear in two or more adjacent grooves, it is time to replace the tires. We recommend, however, that you do not let the tires wear down to this extent.

Worn tires cannot grip the road surface properly and are even less effective on wet roads.

Snow tires lose their traction capability when their tread depth falls below 5/32 in. (4 mm).

In the United States, state laws may govern the minimum tread depth permissible. Follow all such laws.

Excessively-worn Tires

Driving on worn tires can result in loss of control of the vehicle and could cause serious personal injuries or death.

  • Do not drive with worn tires or tires showing cuts or bruises as they may lead to sudden deflation and loss of control which could cause severe personal injury.
  • Specialized high performance tires on high performance sports cars exhibit more wear than those on a family sedan, or even a high performance sedan.
    Therefore, it is important to check your tire pressure and condition at least every two weeks.

If you notice that tires are wearing unevenly, consult your Porsche dealer.

Uneven wear may not always be due to improper wheel alignment. It can be the result of individual driving habits such as cornering at high speeds. If the tire pressure is not checked and adjusted regularly, abnormal tire wear can also occur.

Tire care

  • Avoid damaging tires and wheel rims.
  • If you must drive over a curb or other obstacle, drive slowly and at an obtuse angle.
  • Check tires for uneven wear and damage before driving off.
  • Remove imbedded material.
  • Replace worn or damaged tires immediately.
  • Keep oil, fuel, brake fluid, etc. away from tires.
  • Replace missing valve stem caps.
  • Keep tires inflated correctly.
  • Wash tires when washing the vehicle. Also clean inner side of wheels.
  • Do not use abrasive cleaners when washing the wheels.
  • Check wheel rims for corrosion.
  • Remove road salt, if driving in winter.

Tire damage, puncture
High-pressure cleaning units can damage the tires.

  • Please see the chapter "HIGH-PRESSURE CLEANING UNITS, STEAM CLEANERS" on page 194.
  • Check tires for imbedded material, cuts, punctures, cracks and bulges (side wall) before driving off.

In case of tire damage, where it is uncertain whether there is a break in the ply with all its consequences or tire damage caused by thermal or mechanical 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.

  • Perform a visual inspection if necessary.

Damaged Tire Check

Driving the vehicle with low tire pressure increases risk of a tire failure and resulting loss of control. Furthermore, low tire pressure increases rate of wear of the affected tires.

  • Check tires – including sidewalls – regularly for foreign bodies, nicks, cuts, cracks and bulges.
  • After driving off road, examine tires for signs of damage such as cuts, tears, bulges or foreign objects stuck in the tread. Replace a damaged tire if necessary.
  • Cross curb edges slowly and at right angles if possible.
    Avoid driving over steep or sharp curbs.
  • In cases of doubt, have the wheel (particularly the inner side) checked by an authorized Porsche dealer.