2010 PORSCHE 911 GT3 winter tires

5
Development philosophyPorsche 911 GT3 stands for a sports car with
exceptional performance, both on the road and on
the race track. This objective means that, in the
event of any compromise being required between
sportiness and comfort during the development
process, the tendency will be geared more
towards sportiness. This can result in the following
restrictions in comfort:
– Brake squeal when light pressure applied to
the pedal shortly before stopping.
– Rough engine operation in speed range around
3000 rpm.
– Cracking noise in area of front-axle coil
springs.
– Greater operating force for clutch and gear
shifting.
– Aerodynamic-related extremely low vehicle
position with restrictions in terms of ground
clearance.Sport tiresYour vehicle is equipped with special sport tires
(ultra high performance tires).
This type of tire is approved for use on public
highways and complies with all statutory require-
ments and safety criteria.The design of the tire is also geared towards use
on racing circuits (driver safety training courses,
sports driving schools, Club Sport events) and
provides distinct advantages here in terms of dry
grip and wear compared to conventional road
tires.
The major features are a reduced tread depth and
a special tread pattern and carcass.
Due to ultra high performance design and the
particular manufacturing process of these tires,
they must always be replaced in axle sets (2)
regardless of wear or mileage. Failure to do so
may have a negative affect on the handling charac-
teristics of the vehicle.
The design features of this sports tire result
in the following effects compared with other
summer tires when used under normal
driving conditions:
– Sport tires have a smaller tread depth, and
thus can reach their wear limit sooner.
As with all tires, the attainable mileage
depends on the individual driving style and the
conditions of use.
– Exercise caution when driving on wet roads,
paying special attention to hydroplaning situa-
tions (stagnant water, puddles, lane grooves).
Sport tires have a lower tread depth than
normal tires and you must therefore adapt
speed accordingly when driving on wet
surfaces.– The driver’s skill level must be commensurate
with the vehicle performance levels in the
upper range limits, due to increased safety
risks in the upper range limits.
fAt oudside temperatures below 45 °F (7 °C)
change to winter tires.
fNotify anyone using your car of these charac-
teristics and possible effects.
Danger!
Risk of accident through loss of road surface
contact, control over the vehicle and braking
ability, leading to serious personal injury or
death.
The reduced tire tread depth means that
there is an increased risk of hydroplaning on
wet roads.
fWhen driving on wet or mud-covered roads reduce speed significantly. Danger!
Risk of accident from worn tires.
Sport tires have a smaller tread depth, and
thus can reach their wear limit sooner.
It is important to check tire wear frequently
to avoid risk of serious personal injury or
death from worn tires.
fCheck tire wear frequently.
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136
Instruments, On-Board Computer The tire pressure to be corrected (refill pressure)
is indicated on the displayed wheel.
Example: If “ –1.5 psi (–0.1 bar)” is displayed,
1.5 psi (0.1 bar) must be added to this tire.
Note
The tire pressure menu can only be called up when
the vehicle is stationary.
Calling up the “Info pressure” display
fPush operating lever forward in order to switch
on the selection field.
fSelect “TPM” with the operating lever.
fPush operating lever forward.
The display changes to the tire pressure menu.
fSelect “Info pressure” with the operating lever.
fPush operating lever forward.
Note
After the ignition is switched on, it can take up to
approx. 1 minute before all tire pressures are
displayed. Dashes (“-.-”) appear instead of the tire
pressures. Tire type info in tire pressure menu
Information about the currently set tires:
– Tire type: Summer tires, winter tires
“Info tires” shows the current tire settings.
Calling up the “Info tires” display
fPush operating lever forward in order to switch
on the selection field.
fSelect “TPM” with the operating lever.
fPush operating lever forward.
The display changes to the tire pressure menu.fSelect “Info tires” with the operating lever.
fPush operating lever forward.
Tire selection in the “Set” menu
fPush operating lever forward in order to switch
on the selection field.
fSelect “TPM” with the operating lever.
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188
Practical Tips, Emergency Service
Danger!
Driving on worn tires can result in loss of
control 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,
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 care fAvoid damaging tires and wheel rims.
fI f y o u m u s t d r i v e o v e r a c u r b o r o t h e r o b s t a c l e ,
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, puncture High-pressure cleaning units or steam cleaners
can damage the tires.
fPlease see the chapter “HIGH-PRESSURE
CLEANING EQUIPMENT, STEAM CLEANERS”
on Page 174.
fCheck tires for imbedded material, cuts,
punctures, cracks and bulges (side wall)
before driving off.
In case of tire damage, where it is uncertain
whether there is a break in the ply with all its
consequences 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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190
Practical Tips, Emergency Service
Parking at the curb
Warning!
Hard impacts against curbs (or traffic
islands) are dangerous and may cause
hidden 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.
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 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.
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 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
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.
fCheck this with your authorized Porsche
dealer.
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192
Practical Tips, Emergency Service
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.
fFit winter tires to both axles well before the
cold season begins.
Your authorized Porsche dealer will be pleased
to advise you.
Maintenance note
We recommend fitting snow 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 lose their traction capability when their
tread depth falls below 5/32 in. (4 mm).
Snow chains
Caution!
Risk of damage to body, axle or brake
components.
fFit snow chains only to the rear wheels, and
only with the tire/rim combination listed in the
Technical Data.
To ensure adequate clearance between chain
and body, Porsche recommends only the use
of fine-link chains such as those approved by
Porsche.
fFollow instructions issued by the supplier of the chains.
In order to mount snow chains the vehicle must be
jacked up at the rear.
Different states and countries have varying statu-
tory requirements regarding maximum speed.
Check with local authorities for possible restric-
tions.
fRemove chains as soon as the roads are free
of ice and snow.
Tire designations Due to new speed and load ratings for radial tires,
new designations have come into force for snow
tires for your Porsche.
The designation to be used for ZR tires is e.g.,
265/40 ZR 18 (Z = code letter for radial tires for
speeds above 150 mph / 240 km/h).
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194
Practical Tips, Emergency Service 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.
Speed code letterThe speed code letter indicates the maximum
permissible speed for the tire.
This code letter is shown on the tire sidewall.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.
Inscription on light alloy wheelsMaintenance note
fProtect the valve inserts against soiling with
valve caps.
Use only plastic valve caps.
Soiled valve inserts can cause a gradual loss
of air.
Note on operation
fThe rim width in inches A and the rim offset F
are visible from the outside.
The information is provided on the rear of the
spokes. The rim width and rim offset are also
visible close to the tire valve in some cases.
A- Rim width in inches
B- Rim-flange contour code letter
C- Symbol for drop-center rim
D- Rim diameter in inches
E-Double hump
F- Rim offset in mm
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)
(Y)= up to 186 mph (300 km/h) in accordance
with Y-tires. Speeds in excess of
186 mph (300 km/h) are possible with
a maximum load rating of 85 %
(confirmation of tire manufacturer in excess
of 186 mph (300 km/h) required).
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250
Index Windows .................................................... 177
Anti-crushing protection ......................... 29
Care .................................................. 177
Opening/Closing ................................... 29
Washer nozzles .................................... 76
Washer system ..................... 76, 170, 239
Windshield
Washer nozzles .................................... 76
Wiper blades, changing ....................... 173
Wiper/washer lever ............................... 76
Windshield wipers ................................. 76, 173
Replacing ........................................... 173
Winter operation
Battery ............................................... 213
Coolant .............................................. 158
Engine oil ........................................... 159
Jumper cables ............................ 217, 218
Locks ................................................ 176
Seals ................................................. 179
Snow chains ....................................... 192
Tires .......................................... 191, 238
Washer fluid ....................................... 170
Wiper blades ...................................... 173
Wiper
Blades ............................................... 173
Lever ................................................... 76
Wiper blades
Care .................................................. 177
Changing............................................ 173
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