2004 PORSCHE CAYENNE tires

Minor Repairs
285
Tire lifeTire life depends on various factors, i.e., road sur-
faces, 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 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
regularly, abnormal tire wear can also occur.
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.
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286
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Tire damage, puncturefPlease see the chapter “HIGH-PRESSURE
CLEANING EQUIPMENT, STEAM CLEANERS”
on Page 271.
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.
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
foreign objects stuck in the tread. Replace a
damaged 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 Porsche 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.
I f o n e f a u l t y t i re i s re p l a c e d i t s h o u l d b e n o t e d t h a t
the difference in tread depth on one axle must not
exceed 30%. Handling inconsistencies may result.
fPerform a visual inspection if necessary.
Tire replacementsfUse only tire makes and types tested 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 manufacturer and
with the same specification code (e.g. “N0”,
“N1”...) should be mounted on the vehicle.
Before mounting new tires, check with your
Porsche dealer about the current release
status.
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 and
will affect vehicle performance, safety, and can
affect vehicle warranty.Porsche dealers can recommend the most current
replacement tire options for your vehicle.
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).
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.
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 espe-
cially if only rear tires are replaced. However, this
condition disappears as the new tires are broken
in.
fPlease adjust your driving style accordingly.
Installation of new tires should only be done by a
qualified tire technician.
Valves
fUse only plastic valve caps.
fThe rubber valves must be replaced whenever
the tires are changed.
fThe fitting and replacement specifications
must be observed for metal valves.
fOnly use Original Porsche metal valves.
fProtect the valve inserts against soiling with
valve caps.
Soiled valve inserts can cause a gradual loss
of air.
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287
Parking at the curb
Danger!
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.
fIf you are in doubt, have the wheel checked by
an expert, particularly if you suspect damage
on the inside.
fIf you must drive over a curb or other obstacle,
drive slowly and at an obtuse angle. Exercise care when parking along curbs.
Maintenance Note
Tire repairs are not permissible under any circum-
stances.
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 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 remedied, you might lose
control of your vehicle which could cause
serious personal injury or death.
fStop the vehicle and check the tires.
fIf no cause for the fault can be found, drive ca-
refully to the nearest authorized Porsche dea-ler.
Wheels with Tire Pressure Monitoring
(TPM) sensorsBefore changing wheels, make sure that the
wheels are compatible with your vehicle’s TPM.
fCheck this with your authorized Porsche dea-
ler.
Removing and storing tiresfAfter changing, adjust tire pressure and torque
wheel bolts diagonally.
Please see the chapter “CHANGING WHEELS”
on Page 294.
fStore tires in a cool and dry place. Rotate peri-
odically to avoid flat spots.
fAvoid contact with petrol, oil and grease.
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 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.
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288
Minor Repairs 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 1208, then the tire was produced in the
12th week of 2008.
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 compa-
tibility.
fSnow tires should have the same load capacity
as original equipment tires and should be
mounted on all four wheels.
Winter tires with studs should be run at mode-
rate speeds when new in order to give the
studs time to settle.
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.Maintenance Note
We recommend fitting winter tires on the vehicle at
temperatures below 45 °F (7 °C) since the driving
performance of summer tires is reduced at low
temperatures. Summer tires may be permanently
damaged at extremely low temperatures.
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 gover-
ning 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.
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289
Snow chains
Warning!
Risk of damage to body, axle or brake com-
ponents.
fUse only the fine-link snow chains recommen-
ded and authorized by Porsche so that
sufficient clearance between the wheel well
and the chain is assured.
fPlease see the chapter “TIRES, RIMS, TRACKS”
on Page 350.
fFollow instructions issued by the supplier of the chains.
The best possible handling characteristics are
achieved when snow chains are fitted on all four
wheels of the vehicle. However, it is also possible
to fit snow chains on only one axle (preferably the
rear axle).
fRemove spacers if 18 inch tires, snow chains
or a collapsible spare wheel are mounted.
Caution!
Risk of damage to wheel housings if the
spacers on the rear axle are not removed
before fitting the snow chains.
f17 mm spacers must always be removed from the rear axle when snow chains are to be fitted.
fFor information on the spacers:
Please see the chapter “SPACERS” on
Page 293.
Please see the chapter “CHANGING A WHEEL
WITH REMOVAL OF 17 MM SPACER” on
Page 303.
fBefore fitting chains, remove accumulated ice
and snow from the wheel well.
fVehicles with snow chains must not be driven
faster than 30 mph (50 km/h).
Different states and countries have varying statu-
tory requirements regarding maximum speed.
fCheck with local authorities for possible
restrictions.
fRemove chains as soon as the roads are free
of ice and snow.
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290
Minor Repairs
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
–XL (Extra Load) - Tire with increased load
rating
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.
FRadial
The identification indicates if the tire has radial
structure.
G Term of tubeless or tube tire
Identification for tubeless tires.
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291
Speed code letterThe speed code letter indicates the maximum per-
missible speed for the tire.
This code letter is shown on the tire sidewall.
T = up to 118 mph (190 km/h)
H = up to 131 mph (210 km/h)
V = up to 150 mph (240 km/h)
W = up to 167 mph (270 km/h)
Y = up to 186 mph (300 km/h)
Tip on driving
Tires with a maximum speed rating that is lower
than the specified maximum vehicle speed may be
mounted only if they bear an M+S identification on
the tire sidewall.
fPlease note that in addition to the winter tires,
all-season and all-terrain tires are also subject
to speed limits and bear this identification.
G-Rim width in inches
H- Rim-flange contour code letter
I- Symbol for drop-center rim
J- Rim diameter in inches
K-Double hump
L- Rim offset in mmInscription on light alloy wheelsNote on operation
fThe information is provided on the spoke. The
rim width in inches G and the rim offset L are
visible from the outside. This information can
be found near the tire valve.
A-Tool boxJackThe jack is located in tool box A under the load-
space floor.
fPlease see the chapter “OPENING
LOADSPACE FLOOR” on Page 207.
Note
The tools required for changing a wheel (e.g. jack,
wheel bolt wrench, assembly aids, folding
wedges) are only supplied with the vehicle if the
vehicle comes with a collapsible spare wheel or
full-size spare wheel as standard. Your authorized
Porsche dealer will be pleased to advise you.
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Minor Repairs
Warning!
The jack must be used only to raise the car
for wheel changing.
The jack must never be used as a support to
work underneath the vehicle. If the jack is
accidentally dislodged, you or bystanders
could suffer severe personal injury.
fNever jack up other vehicle or other loads with
the jack.
fAlways place the car on stable supports if you
have to work under the car.
When working under the vehicle, always use
safety stands specifically designed for this pur-pose.
Tool KitTo o l b o x A and compressor with pressure tester
on non-air suspension vehicles are located under
the cargo area.
Notes on operation
On vehicles with a collapsible spare wheel or full-
size spare wheel as standard, the screwdriver is
stored in the handle of the wheel bolt wrench.
A-CompressorCompressorOn vehicles without level-control systems, there is
an additional compressor with pressure tester
under the loadspace floor.
fPlease see the chapter “CHECKING TIRE PRES-
SURE WITH A PRESSURE GAGE” on Page 306.
On vehicles with level control, you can use the
compressor of the level-control system to fill the
tires.
The bag with the tire filling hose is located under
the loadspace floor in the spare-wheel recess.
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