280
Practical Tips, Minor Repairs
Tire pressures
Danger!
Risk of accident.
Risk of serious personal injury or death.
Driving the vehicle with low tire pressure
increases risk of a tire failure and resulting
loss of control. Furthermore, low tire pres-
sure increases rate of wear of the affected
tires and cause damage. Always use an
accurate tire pressure gauge when checking
inflation pressures.
fDo not exceed the maximum tire pressure
listed on the tire sidewall. (Also refer to “Tech-
nical data“).
fCold tire inflation pressure means: all tires
must be cold, ambient temperature maximum
68°F (20°C), when adjusting the inflation pres-
sure. Avoid sunlight striking the tires before
measuring cold pressures, since the pressures
would rise from temperature influence.
fValve caps protect the valve from dust and dirt,
and thus from leakage. Always screw caps
tightly down. Replace missing caps immedi-
ately.
fFor safety reasons, don't use tire inflating bot-tles.The tire pressure must match the prescribed
value.
You can find information on the tire pressure:
– In the front left door aperture.
– Please observe the chapter “TIRE
PRESSURES, COLD” on Page 361.
These values are for cold tires (68°F/20 °C).
fCheck the tire pressure at least every
2 weeks. Always check when tires are cold.
fOn vehicles with tire pressure monitoring
system:
Please observe the chapter “TIRE PRESSURE
MENU” on Page 89.
When tires are warm, the tire pressure is
increased.
fNever let air out of hot tires. This could cause
the tire pressure to fall below the prescribed
value.
Insufficient tire pressure can cause tires to
overheat and thus be damaged – even invisibly.
Hidden tire damage is not eliminated by subse-
quently correcting the tire pressure.Overloading
Danger!
Risk of personal injury, loss of control and
damage to vehicle parts.
fDo not overload your vehicle. Be careful about
the roof load.
fIf loading the vehicle also correct the tire pres-
sure. Tire pressure for loaded vehicle can be
found on the tire pressure plate and in the
chapter technical data.
fNever exceed the specified axle load.
Overloading can shorten the service life of the
tires and car, as well as lead to dangerous vehi-
cle reactions and long braking distances.
Damage due to overloading is not covered by the vehicle warranty.
fPlease observe the chapter “LOADING INFOR-
MATION” on Page 195.
fPlease observe the chapter “TIRE PRES-
SURES, COLD” on Page 361.
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281
Example of a tire pressure plate ATire Pressure plateDepending on when your vehicle was manufac-
tured, the tire pressure plate on the driver's door
will contain different data.
Information on the tire pressure plate A
A Seating capacity
Maximum number of vehicle occupants, includ-
ing the driver.B Vehicle load limit
Is the maximum total weight limit specified of
the load (passengers and cargo) for the vehi-
cle. This is the maximum weight of passengers
and cargo that can be loaded into the vehicle.
If a trailer is being towed, the trailer tongue
weight must be included as part of the cargo
load.Please observe the chapter “LOADING
INFORMATION” on Page 195.
C Original tire size
Size of tires mounted at the factory.
D Recommended cold tire inflation pressure
These values are for cold tires (68°F/20 °C).
E Approved tire sizes
F Size and tire pressure for the collapsible spare
wheel
Example of a tire pressure plate BInformation on the tire pressure plate B
A Approved tire size
B Permissible tire pressure for the front axle
C Tire pressure for fully loaded or partially
loaded vehicle
D Permissible tire pressure for the rear axle
E Size and tire pressure for the collapsible spare
wheel
282
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.
Practical Tips, Minor Repairs
283
Tire carefAvoid damaging tires and wheel rims.
fIf you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
fCheck tires for uneven wear and damage
before driving off.
fRemove imbedded material.
fReplace worn or damaged tires immediately.
fKeep oil, fuel, brake fluid, etc. away from tires.
fReplace missing valve stem caps.
fKeep tires inflated correctly.
fWash tires when washing the vehicle. Also
clean inner side of wheels.
fDo not use abrasive cleaners when washing
the wheels.
fCheck wheel rims for corrosion.
fRemove road salt, if driving in winter.
Tire damage, puncturefPlease observe the chapter “HIGH-PRESSURE
CLEANING UNITS” on Page 266.
Danger!
Risk of serious personal injury or death.
Driving the vehicle with low tire pressure
increases increases risk of a tire failure and
resulting loss of control. Furthermore, low
tire pressure increases rate of wear of the
affected tires.
fCheck tires – including sidewalls – regularly for
foreign bodies, nicks, cuts, cracks and bulges.
fAfter driving off road, examine tires for signs
of damage such as cuts, tears, bulges or for-
eign objects stuck in the tread. Replace a dam-
aged tire if necessary.
fCross curb edges slowly and at right angles if
possible.
Avoid driving over steep or sharp curbs.
fIn cases of doubt, have the wheel (particularly
the inner side) checked by an authorized Por-sche dealer.In case of tire damage, where it is uncertain
whether there is a break in the ply with all its con-
sequences 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.
fPerform a visual inspection if necessary.
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Practical Tips, Minor Repairs
Removing and storing tiresfAfter changing, adjust tire pressure and torque
wheel bolts diagonally.
Please observe the chapter “CHANGING
WHEELS” on Page 294.
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 perception that tire durability and perfor-
mance are not affected by storage and age is
unfounded.
Chemical additives, which make the rubber elas-
tic, lose their effectiveness over 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 num-
bers read 1204, then the tire was produced in the
12th week of 2004.
fStore tires in a cool and dry place.
fRotate periodically to avoid flat spots.
Snow tiresThe installation of Porsche approved winter tires is
recommended.
Use Porsche approved winter tires for grip on
snow and ice. For optimum performance, stud-
ding can be considered.
Check with your local Motor Vehicle Bureau for
possible restrictions.
Danger!
Risk of loss of control and damage to the
vehicle as well as serious personal injury or
death.
The standard tires profile and rubber mixture
are optimized for wet and dry driving condi-
tions, and may not prove favorable for snow
conditions.
fInstall winter tires before driving in such condi-tions.
Before mounting winter tires, consult with your
Porsche dealer. He has the technical information
necessary to advise you on wheel and tire compat-
ibility.
S n o w t i re s s h o u l d h a v e t h e s a m e l o a d c a p a c i t y a s
original equipment tires and should be mounted on
all four wheels.
Winter tires with studs should be run at moderate
speeds when new in order to give the studs time
to settle.
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287
Danger!
Risk of serious personal injury or death.
Driving the vehicle with low tire pressure
increases increases risk of a tire failure and
resulting loss of control. Furthermore, low
tire pressure increases rate of wear of the
affected tires and cause damage.
Tires with badly worn treads and studs are
very dangerous and could cause accidents
resulting in serious personal injuries or
death.
fMake sure they are replaced immediately.
fDo not exceed the winter tire speed rating.
Snow tires do not have the same degree of trac-
tion on dry, wet or snowfree roads as normal tires.
Furthermore, snow tires wear rapidly under these
conditions.
Winter tires do not fulfill their purpose if the tread
depth is less than 5/32 in. (4 mm).
Comply with all state and local laws govern-
ing snow tire and tread depth requirements.
Danger!
Risk of accident and serious personal injury
or death due to excessive speed.
fAlways check the maximum speed rating on
the tire sidewall on any tire on the vehicle.
fNever exceed the maximum speed rating of the tires.
Wheel change
fWhen wheels are removed, mark the direction
of rotation and position of each wheel.
Example: FR (front right), FL, RR and RL.
fAlways fit the wheels in accordance with the
markings.
Practical Tips, Minor Repairs
289
Example of InscriptionInscription on radial tireATire size
Example: P 255/55R18 109 Y
–P - The tire is designed for Passenger vehicle.
This information is not included on all tires.
–255 - Indication of tire width in mm
–55- Indication of tire height to tire width ratio
in percent
–R- Belt type code letter for radial–18 - Indication of rim diameter in inches
–109 - Load capacity coefficient
–Y - Speed code letter
B TIN (Tire Identification Number)
Example: DOT xx xx xxxx xxxx
–DOT
The DOT symbol indicates that the tires com-
ply with the requirements of the US Depart-
ment of Transportation and provides informa-
tion about:
– first two-digit code means manufacture’s iden-
tification mark.
– second two-digit code means tire size.
– third four-digit code means tire type code.
– fourth four-digit code means date of manufac-
ture.
If, for example, the last four numbers read
1204, the tire was produced in the 12th week
of 2004.
C Tire ply composition and material
The number of layers in the tread and sidewalls
and their material composition.
D Maximum permissible inflation pressure
The maximum permissible cold inflation pressure
to which a tire can be inflated.
fDo not exceed the permissible inflation pres-
sure.
E Maximum Load rating
The maximum load in kilograms and pounds can
be carried by the tire. If you replace tires always
use a tire that has the same maximum load rating
as the factory installed tire.
F Term of tubeless or tube tire
Identification for tubeless tires.
GRadial
The identification indicates if the tire has radial
structure.
Practical Tips, Minor Repairs
293
CompressorOn vehicles without level-control systems, there is
an additional compressor with pressure tester
under the loadspace floor.
On vehicles with level control, you can use the
compressor of the level-control system to fill the
tires.
The filler hose required for this purpose can be
found under the left rear seat.
fPlease observe the chapter “FOLDING REAR
SEATS FORWARD” on Page 37.
fPlease observe the chapter “INFLATING TIRES
ON VEHICLES WITHOUT AIR SUSPENSION” on
Page 303.
Wheel BoltsfAlways clean the wheel bolts before installing.
Maintenance note
fWheel bolts must not be greased.
fReplace damaged wheel bolts.
Only use the original Porsche wheel bolts spe-
cially designed for this vehicle type.Tightening torque
Tightening torque of the wheel bolts 118 ftlb.
(160 Nm).
Security wheel boltsThe adapter (wrench socket) for the security
wheel bolts is located in the tool box.
To loosen or tighten the wheel bolt with anti-theft
protection, the adapter must be used between the
wheel bolt and the wheel bolt wrench.
fWhen positioning the wrench socket, ensure
that it engages fully in the teeth of the wheel
bolt.
Note on operation
If the wheels have to be removed at the workshop,
please do not forget to hand over the socket for
the security wheel bolts along with the car key.