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302
Practical Tips, Minor Repairs
Tire traction
Warning!
When driving on wet or slushy roads, a
wedge of water may build up between the
tires and the road. This phenomenon is
known as “hydroplane“ and may cause par-
tial or complete loss of traction, vehicle con-
trol or stopping ability.
fReduce speed on wet surfaces to prevent this.Tire lifeTire life depends on various factors, i.e., road sur-
faces, traffic and weather conditions, driving hab-
its, type of tires and tire care.
fInspect your tires for wear and damage before
driving off. If you notice uneven or substantial
wear, wheels might need alignment or tires
should be balanced or replaced.
Tire wearThe 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 adja-
cent 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.
In the United States, state laws may govern the
minimum tread depth permissible. Follow all such
laws.
Danger!
Driving on worn tires can result in loss of con-
trol of the vehicle and could cause serious
personal injuries or death.
fDo 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.
fSpecialized high performance tires on high
performance sport utility vehicles 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.
fIf 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 reg-
ularly, abnormal tire wear can also occur.
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Practical Tips, Minor Repairs
305
Wheel alignment, wheel balancingAs 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.
Danger!
If, during a journey, uneven running or vibra-
tions 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 hav-
ing the cause of the fault remedied, you
might lose control of your vehicle which
could cause severe personal injury.
fStop the vehicle and check the tires.
fIf no cause for the fault can be found, drive
carefully to the nearest authorized Porsche dealer.
Page 401 of 420

Index
401
UUltrasonic measurement .............................. 182
Ultrasound sensors, ParkAssist.................... 180
Ultrasound sources ..................................... 182
Undercoating .............................................. 289
Unlocking, keyless ........................................ 22
Immobilizer........................................... 23
Uphill driving............................................... 248
Traction ............................................. 248VVehicle
Battery ............................. 191
, 344
, 357
Care .................................................. 284
Data bank........................................... 378
Identification number ........................... 378
Keys ........................................... 17, 358
Laying up ........................................... 293
Lowering ............................................ 256
Putting into operation .......................... 345
Raising ............................................... 255
Recovery ............................................ 376
Securing against rolling ....................... 316
Storage.............................................. 345
Transport ...................... 21
, 23, 29, 256
Washing ............................................. 285Vehicle door
Locking .........................................21
, 23
Unlocking .............................................20
Vehicle key
Battery ...............................................358
Ventilation.................................144
, 148
, 152
Vents .........................................................143
Central ......................................150, 156
Footwell ....................................150, 156
Side ..........................................150, 156
Vertical coupling load..................................213
Voltmeter .....................................................90
Battery/generator warning .....................90
WWarning triangle ..........................................196
Warnings ....................................................100
Washer fluid
Level ..................................................270
Topping up .........................................270
Washer system, windshield wipers ................138
Washing .....................................................285
Water crossing ...........................................250
Weights ......................................................387
Wheel alignment..........................................305
Wheel bolts ................................................313
Removing ..................................322
, 331
Wheel change .............................................307
Wheels ..............................................290, 297
Adjusting ............................................305
Change .....................................315, 322
Storing ...............................................306
Tracks................................................382
Wheel balancing .........................244, 305Windows.................................................... 288
Windshield ............................... 150
, 156
, 270
Windshield wiper/washer stalk .................... 137
Windshield wipers..................... 139
, 204
, 273
Blades ............................................... 288
Front ................................................. 138
Rear .................................................. 139
Switch ............................................... 137
Winter
Driving............................................... 345
Tires ................................................. 382
Wiper blades..................................... 273, 288
Changing .................................. 273, 275
Working on your vehicle .............................. 260