2009 PORSCHE CAYMAN tire pressure

Practical Tips, Emergency Service
215
Each tire, including the spare (if provided) should
be checked monthly when cold and inflated to the
inflation pressure recommended by the vehicle
manufacturer on the vehicle placard or tire infla-
tion pressure label. (If your vehicle has tires of a
different size than the size indicated on the vehicle
placard or tire inflation pressure label, you should
determine the proper tire inflation pressure for
those tires.)
As an added safety feature, your vehicle has been
equipped with a tire pressure monitoring (TPM)
that illuminates a low tire pressure telltale when
one or more of your tires is significantly under-in-
flated. Accordingly, when the low tire pressure tell-
tale illuminates, you should stop and check your
tires as soon as possible, and inflate them to the
proper pressure. Driving on a significantly under-
inflated tire causes the tire to overheat and can
lead to tire failure. Under-inflation also reduces
fuel efficiency and tire tread life, and may affect
the vehicle’s handling and stopping ability.
Please note that the TP M is not a substitute for
proper tire maintenance, and it is the driver’s re-
sponsibility to maintain correct tire pressure, even
if under-inflation has not reached the level to trig-
ger illumination of the TP M low tire pressure tell-
tale.
f On vehicles with tire pressure monitoring:
Please see the chapter “TPM TIRE PRESSURE
MONITORING” on Page 151.
When tires are warm, the tire pressure is
increased. f
Never let air out of hot tires.
This could cause the tire pressure to fall below
the prescribed value.
Insufficient tire filling 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 damage to vehicle parts, loss of con-
trol and serious personal injury or death.
f Do not overload your vehicle. Be careful about
the roof load.
f If 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.
f Never exceed the specified axle load.
Overloading can shorten the service life of the
tires and car, as well as lead to dangerous ve-
hicle reactions and long braking distances.
Damage due to overloading is not covered by the vehicle warranty.
f Please see the chapter “LOADING INFORMA-
TION” on Page 224.
f Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/ 20 °C)” on Page 267.
Example of a tire pressure plateTire pressure plateInformation on the tire pressure plate
A Seating capacity
Maximum number of vehicle occupants, inclu-
ding the driver.

216
Practical Tips, Emergency Service
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.
Please see the chapter “LOADING INFORMA-
TION” on Page 224.
C Tire size for the front axle Check with your authorized Porsche dealer
about the current release status.
D Recommended tire pre ssure for the front axle
These values are for cold tires (68 °F/20 °C).
E Tire size for the rear axle Check with your authorized Porsche dealer
about the current release status.
F Recommended tire pressure for the rear axle. These values are for cold tires (68 °F/20 °C).
G In vehicles with collapsible spare wheel: Size and tire pressure of the spare wheel.
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
control or stopping ability.
f Reduce speed on wet surface to prevent this. Tire life Tire life depends on vari ous factors, i. e., road
surfaces, traffic and wea ther conditions, driving
habits, type of tires and tire care.
f Inspect 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 wear The original equipment tires on your Porsche have
built-in tire wear indicato rs. 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.
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.

Practical Tips, Emergency Service
217
Danger!
Driving on worn tires can result in loss of con-
trol of the vehicle an d could cause serious
personal injuries or death.
f 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.
f 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, con-
sult 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 f Avoid damaging tires and wheel rims.
f If you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle.
f Check tires for uneven wear and damage
before driving off.
f Remove imbedded material.
f Replace worn or damaged tires immediately.
f Keep oil, fuel, brake fluid, etc. away from tires.
f Replace missing valve stem caps.
f Keep tires inflated correctly.
f Wash tires when washing the vehicle. Also
clean inner side of wheels.
f Do not use abrasive cleaners when washing
the wheels.
f Check wheel rims for corrosion.
f Remove road salt, if driving in winter.
Tire damage, puncture High-pressure cleaning units can damage the
tires.
f Please see the chapter “HIGH-PRESSURE
CLEANING UNITS, STEAM CLEANERS” on
Page 203.
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.

218
Practical Tips, Emergency Service
Danger!
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.
f Check tires – including sidewalls – regularly for
foreign bodies, nicks, cuts, cracks and bulges.
f After 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.
f Cross curb edges slowly and at right angles if
possible.
Avoid driving over steep or sharp curbs.
f In cases of doubt, have the wheel (particularly
the inner side) checked by an authorized Porsche dealer.
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 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 sh ould 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.
f 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.
f Use only plastic valve caps.

Practical Tips, Emergency Service
219
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 serious personal injury
or death.
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.
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 weight s 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 au-
thorized Porsche dealer.
Warning!
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 reme died, you might lose
control of your vehicle which could cause se-
rious personal injury or death.
f Stop the vehicle and check the tires.
f If no cause for the fault can be found, drive
carefully to the nearest authorized Porsche dealer.
Wheels with Tire Pressure Monitoring
(TPM) sensorsBefore changing wheels, make sure that the
wheels are compatible with your vehicle's TPM.
f Check this with your authorized Porsche
dealer.Removing and storing tires fAfter changing, adjust tire pressure and torque
wheel bolts diagonally to 94 ftlb (130 Nm).
Tires must always remain on the same side of
the vehicle.
When wheels are removed, the direction of
rotation 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 perform-
ance are immune to the effects of storage and
age is unfounded.
Chemical additives, whic h make the rubber elas-
tic, lose their effectivene ss in the course of time
and the rubber becomes brittle and cracks.
Therefore, the tires should be inspected from
time to time.

222
Practical Tips, Emergency Service
Example of InscriptionInscription on radial tireATire size
Example: P 295/30 ZR 19 100 Y
–P - The tire is designed for Passenger vehicle.
This information is not included on all tires.
– 295 - Indication of tire width in mm
– 30 - Indication of tire height to tire width ratio
in percent –
ZR - code letter for radial tires for speeds
above 150 mph / 240 km/h
There are currently no standards concerning
tire strength at speeds above 150 mph
(240 km/h).
– R - Belt type code letter for radial
– 19 - Indication of rim diameter in inches
– 100 - Load capacity coefficient
– Y - Speed code letter
– XL (Extra Load) - Tire with increased load rat-
ing
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 manufacturer’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
0208, the tire was produced in the 2nd week
of 2008.
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.
f Do not exceed the permissible inflation
pressure.

224
Practical Tips, Emergency Service
Loading InformationDefinitionsThe Curb weight - actual weight of your vehicle -
vehicle weight including standard and optional
equipment, fluids and emergency tools. This
weight does not include passengers and cargo.
The Gross Vehicle Weight is sum of the curb
weight and the weight of passengers and cargo
combined.
The Gross Vehicle Weight Rating is the maxi-
mum total weight of vehicl e, passengers, luggage
and optional equipment.
The Gross Axle Weight Rating is the maximum
load limit for the front or the rear axle. This infor-
mation is located on the safety compliance sticker
located in the driver’s side door jamb.
For determining the compat ibility of the tire and
vehicle load capabilities:
f Please see the chapter “TECHNICAL DATA” on
Page 266.
The load capacity coeffici ent (e.g. “100”) is a min-
imum requirement. The Gross Combined Weight Rating is the
maximum total weight rating of vehicle, passen-
gers and cargo.
The Vehicle Capacity Weight
- Load Limit - is
the maximum total weight limit specified of the
load (passengers and cargo) for the vehicle. This
is the maximum weight of passengers and cargo
that can be loaded into the vehicle. This informa-
tion can be found on the tire pressure plate.
The maximum loaded vehicle weight is the
sum of curb weight, accessory weight, vehicle ca-
pacity weight and production options weight.
The load rating is the maximum load that a tire
is rated to carry for a given inflation pressure.
The maximum load rating is the load rating for
a tire at the maximum permissble inflation pres-
sure.
The cargo capacity is the permissible weight of
cargo, the substracted weight of passengers from
the load limit.
f Never exceed the permissible limits.
Danger!
Risk of loss of control, damage to the vehicle
and serious personal injury or death.
f Never exceed the specified axle loads.
Overloading can shorten the service life of the
tires and car, as well as lead to dangerous
vehicle reactions and long braking distances.
Damage due to overloading is not covered by the vehicle warranty.

Practical Tips, Emergency Service
225
Example for determining the combined weight of
occupants and cargoVehicle Load CapacityfThe combined weight of occupants and cargo
should never exceed the weight shown on the
tire plate in the vehicle.
Please see the chapter “TIRE PRESSURE PLA-
TE” on Page 265.
f Never exceed the number of passengers
shown on the tire pressure plate in the vehicle. Determining the combined weight of
occupants and cargo:
f
Add the weight of all occupants and then add
the total luggage weight ( figure).
Steps for determining correct load limit
1. Locate the statement "The combined weight of occupants and cargo should never exceed XXX
pounds" on your vehicle’s placard (depending
on the date of manufacture).
2. Determine the combined weight of the driver and passengers that will be riding in your vehi-
cle. 3. Subtract the combined weight of the driver and
passengers from XXX kilograms or XXX
pounds.
4. The resulting figure equals the available amount of cargo and luggage load capacity.
For example, if the ”XXX“ amount equals
400 lbs. and there will be two - 150 lb passen-
gers in your vehicle, the amount of available
cargo and luggage load capacity is 100 lbs.
(400 - 300 (2 x 150) = 100 lbs.).
5. Determine the combined weight of luggage and cargo being loaded on the vehicle. That
weight may not safely ex ceed the available car-
go and luggage load capacity calculated in
Step 4.