2005 PORSCHE 911 CARRERA tires

206
Maintenance, Car Care
Alcantara fDo not use a leather care product to clean
Alcantara.
For regular care it is sufficient to clean the cover
with a soft brush.
Cleaning when lightly soiled
fWet a soft cloth with water or a neutral soap
solution and wipe off the dirt.
Cleaning when heavily soiled
fWet a soft cloth with lukewarm water or
thinned white spirit and dab the dirt from the
outside in. Safety belts If it becomes necessary to clean the belts, you
can use any mild washing agent.
Allow the belts to dry prior to retracting, but avoid
direct sunlight.
fOnly use suitable cleaners.
If unsuitable cleaners are used or any attempt
is made to dye or bleach the belts, the web-
bing may be weakened and thus constitute a
safety risk.
Storing your Porsche If you intend to store your Porsche for a prolonged
period, please consult your authorized Porsche
dealer. The staff will be glad to advise you on the
most suitable and necessary methods.
fClean your vehicle thoroughly inside and out-
side.
Clean the engine compartment.
The under carriage and chassis components
should be free of dirt and salt deposits.
fFill up the fuel tank.
fChange the oil and oil filter, and run the engine
for several minutes.
fIncrease the tire pressure to 58 psi (4 bar).
It is not recommended to lift the vehicle, due to
the possibility of corrosion on shock absorber
piston shafts.
The vehicle should be moved slightly, approxi-
mately every four weeks, to prevent flat spot
on the tires. Climate control
The air conditioning system should be in good
working condition and fully charged.
Windshield/Headlight washer
fCheck and correct antifreeze/cleaning solution
level as necessary.
Electrical system
fRemove the battery from the vehicle and store
it in a cool dry place, not on a cement floor.
When the battery is disconnected, the
alarm system is deactivated.
fRecharge the battery every 3 months. If the
battery remains in the vehicle with the cables
connected, it is necessary to check, remove
and recharge the battery every 2-3 weeks.
Do not fast charge the battery.
fPlease observe the chapter “BATTERY” on
Page 236.
Vehicle interior
The interior must be dry, especially in the area of
the floor carpets. The use of drying agents (Silica-
Gel) is recommended in vehicles with leather inte-
rior and in areas with high humidity. The recom-
mended amount is 3 fabric bags of 1.1 lbs.
(500 grams) each placed on the floor carpets.
Windows, doors and lids must be closed. The air
vents should be opened.

Practical Tips, Emergency Service
207 Practical Tips, Emergency Service
Exercise Extreme Caution
when Working on your Vehicle .................... 208
Tires/Wheels ............................................ 209
Loading Information................................... 222
Lifting the Vehicle with a Lifting Platform
or Garage Lift ........................................... 224
Flat Tire .................................................... 225
Wheel Bolts .............................................. 228
Electrical System ...................................... 232
Battery ..................................................... 236
Emergency Starting with Jumper Cables ..... 242
Lights, Replacing Bulbs.............................. 244
Headlights ................................................ 246
Tail Light .................................................. 254
License Plate Light .................................... 255
Luggage Compartment/
Engine Compartment/Footwell Light ........... 255
Door Guard/Curb Light .............................. 255
Interior Light, Reading Lights...................... 256
Adjusting Headlights .................................. 257
Towing ..................................................... 259

Practical Tips, Emergency Service
209
Tires/Wheels The original equipment tires and wheel rims on
your Porsche comply with all applicable Federal
Motor Vehicle Safety Standards.
For your safety remember the following:
– Wheel rims and wheel bolts are matched to fit
your Porsche.
– If you intend to use other than original equip-
ment wheels, be sure that they conform to
Porsche specifications for your model.
Only tires with the same make and with the
same specification code (e.g. “N0”, “N1”...)
can be mounted.
– The use of wheel rims and wheel bolts that do
not meet specifications of the original factory
installed equipment will affect the safe opera-
tion of your vehicle.
– Before you plan on exchanging wheels, or
snow tires already mounted on the wheel rims,
consult your authorized Porsche dealer. Your
dealer has the technical information necessary
to advise you which wheel rims and wheel bolts
are compatible with the original factory instal-
lations.
Danger!
Risk of loss of control and serious personal
injury or death.
fIf while driving, your vehicle experiences a sud-
den vibration or ride disturbance, and/or you
suspect that possible damage to your tires or
vehicle has occurred, you should immediately
reduce your speed without excessive use of
the brakes.
fStop the vehicle as soon as possible, and in-
spect the tires.
If you cannot determine the cause for the dis-
turbance, have your vehicle towed to the near-
est Porsche or tire dealer to have your vehicle
or tire(s) inspected.
fContinuing to operate the vehicle without cor-
rection could result in a loss of control and serious personal injury.

210
Practical Tips, Emergency Service
Uniform Tire Quality Grading Quality grades can be found where applicable on
the tire sidewall between tread shoulder and max-
imum section width.
Example All passenger car tires must conform to Federal
Safety Requirements in addition to these grades. Treadwear
The treadwear grade is a comparative rating
based on the wear rate of the tire when tested un-
der controlled conditions on a specific govern-
ment test course.
For example, a tire graded 150 would wear one
and a half (1-1/2) times as well on the government
course as a tire graded 100.
The relative performance of tires depends upon
the actual conditions of their use, however, and
may depart significantly from the norm due to var-
iations in driving habits, service practices and dif-
ferences in road characteristics and climate.

Practical Tips, Emergency Service
211
Traction AA, A, B, C
The traction grades, from highest to lowest, are
AA, A, B, and C and they represent the tire’s ability
to stop on wet pavement as measured under con-
trolled conditions on specified government test
surfaces of asphalt and concrete.
A tire marked C may have poor traction perform-
ance.
Warning!
The traction grade assigned to this is based on
braking (straight-ahead) traction tests and does
not include cornering (turned) traction, accelera-
tion, hydroplaning or peak traction characteris-
tics. Temperature A, B, C
The temperature grades are A (the highest), B and
C, representing the tire’s resistance to the gener-
ation of heat and its ability to dissipate heat when
tested under controlled conditions on a specified
indoor laboratory test wheel.
Sustained high temperatures can cause the mate-
rial of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire failure.
The grade C corresponds to a level of perform-
ance which all passenger car tires must meet un-
der the Federal Motor Vehicle Safety Standard No.
109.
Grades B and A represent higher levels of per-
formance on the laboratory test wheel than the
minimum required by law.
Warning!
The temperature grade for this tire is established
for a tire that is properly inflated and not overload-
ed.
Excessive speed, underinflation, or excessive
loading, either separately or in combination, can
cause heat buildup and possible tire failure.

212
Practical Tips, Emergency Service
Tire pressures
Warning!
Incorrect tire pressure causes increased tire
wear and adversely affects road handling.
fAlways use an accurate tire pressure gauge
when checking inflation pressures.
fDo not exceed the maximum tire pressure list-
ed on the tire sidewall.
Please observe the chapter “TIRE PRESSURE
PLATE” on Page 263.
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 measur-
ing 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 immediately.
fUse only plastic valve caps.
fDo not use commercially available sealant or
tire inflating bottles. Only use Porsche approved tire sealant.The tire pressure must match the prescribed val-
ue.
You can find information on tire pressure:
– on Page 5 of this Owner’s Manual
– and in the left door aperture.
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.
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 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 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 ve-
hicle 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 222.
fPlease observe the chapter “TIRE PRESSURES
FOR COLD TIRES” on Page 267.

Practical Tips, Emergency Service
213
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
aperture 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 INFOR-
MATION” on Page 222.
C Tire size for the front axle
Check with your authorized Porsche dealer
about the current release status.
D Recommended tire pressure 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
Example of a tire pressure plate BInformation on the tire pressure plate B
A Information for tire sealant, seating capacity,
vehicle load limit
B Approved tire size for the front axle
C Permissible tire pressure for the front axle
D Tire pressure for fully loaded or partially
loaded vehicle
E Permissible tire pressure for the rear axle
F Approved tire size for the rear axle

214
Practical Tips, Emergency Service
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.
fReduce speed on wet surface to prevent this. Tire life Tire life depends on various factors, i. e., road
surfaces, traffic and weather conditions, driving
habits, 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 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 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 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.