tire type PORSCHE 911 GT3 2010 5.G Owners Manual

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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58
Operation, Safety When the ignition is switched on the ABS warning
light will light up while the system is electronically
interrogated and goes out when the engine is
started if the check is not yet complete.
If the ABS warning lamp fails to go out, this
indicates that ABS has been deactivated due to a
fault. If the warning lights in the instrument panel
and on-board computer light up while you are
driving, this indicates that a fault has occurred. In
both cases, normal braking, as in vehicles without
ABS, is still retained.
The ABS system should, however, be examined at
an authorized Porsche dealer immediately to
prevent the occurrence of further faults.
fIf the ABS system becomes inoperative, take
your vehicle to your authorized Porsche dealer
immediately.
Warning!
Risk of an accident, resulting in serious
personal injury or death.
The control unit of the ABS brake system is
set for standard tire size. If non-standard
tires are installed, the control unit may misin-
terpret the speed of the vehicle, because of
the variant data it receives from the sensors
on the axles.
fUse only tire makes and types tested by Porsche.
Warning light USA
Warning light Canada
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134
Instruments, On-Board Computer
TPM
Tire Pressure MonitoringfPlease see the chapter “TIRE PRESSURES FOR
COLD TIRES 68 °F/20 °C” on Page 237.
The Tire Pressure Monitoring continuously
monitors tire pressure and tire temperature on all
four wheels and warns the driver when the tire
pressure is too low.
The display as well as the settings for the Tire
Pressure Monitoring take place on the on-board
computer.
However, you must still adjust the tire pressure on
the wheel.fThe driver is responsible for filling the tires
correctly and making the correct settings on
the on-board computer.
The Tire Pressure Monitoring offers the following
functions:
– Display of the actual tire pressure while the
vehicle is in motion.
– Display of the deviation from the required
pressure (refilling pressure).
– Display of currently set tire type.
– Tire pressure warnings in two stages.
Warning!
Despite the advantages offered by the Tire
Pressure Monitoring, it is still the driver’s
responsibility to update the corresponding
settings in the on-board computer and
maintain the pressure in the tires.
Low tire pressure reduces the road safety of
the vehicle and destroys the tire and wheel.
fWhen a flat tire has been displayed, immedia-
tely stop in a suitable place and check the tires
for damage. If necessary, remedy the damage
with a tire sealant.
fDo not by any means continue to drive with
damaged tires.
fSealing the tire with tire sealant is only an
emergency repair, so you can drive to the next
authorized Porsche dealer. The maximum
permitted speed is 50 mph (80 km/h).fDo not drive with tires whose tire pressure
drops again in a short period of time. In cases
of doubt, have tires checked by an authorized
Porsche dealer.
fDamaged tires must be immediately replaced
by an authorized Porsche dealer.
Tire repairs are not permissible under any
circumstances.
fIf a fault occurs in the Tire Pressure Monitoring
(e.g. defective wheel transmitter), contact an
authorized Porsche dealer immediately and
have the damage repaired.
The tire pressure will not be monitored at all or
will be monitored only partially by defective
Tire Pressure Monitoring.
fTires lose air over time without a tire defect
being present. A tire pressure warning will then
appear in the on-board computer display.
Correct the tire pressure at the next oppor-
tunity.
fThe Tire Pressure Monitoring gives a warning
about tire damage due to natural pressure loss
as well as about a gradual loss of pressure due
to foreign objects.
The Tire Pressure Mnitoring cannot warn you
about tire damage that occurs suddenly (e.g.
flat tire due to abrupt external effects).
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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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Instruments, On-Board Computer
137
fPush operating lever forward.
The display changes to the tire pressure menu.fSelect “Set” with the operating lever.fPush the operating lever forward.
fSelect desired tire type:
summer or winter.
fPush operating lever forward.
A display for confirming the selected type of
tire appears.
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Practical Tips, Emergency Service
187
B Vehicle load limit
Is the maximum total weight limit specified of
the load (passengers and cargo) for the
vehicle. This is the maximum weight of passen-
gers and cargo that can be loaded into the
vehicle.
Please see the chapter “LOADING INFORMA-
TION” on Page 195.
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.
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
partial 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
adjacent 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.
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Practical Tips, Emergency Service
189
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
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
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.
Tire replacements If in doubt, contact your authorized 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
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
Please observe the installation and replacement
instructions for valves.
fUse only genuine Porsche metal valves.
fProtect the valve inserts against soiling with
valve caps.
Soiled valve inserts can cause a gradual loss
of air.
fUse only plastic valve caps.
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Practical Tips, Emergency Service
193
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
rating
B TIN (Tire Identification Number)
Example: DOT xx xx xxxx xxxx
–DOT
The DOT symbol indicates that the tires
comply with the requirements of the US
Department of Transportation and provides
information about:
– first two-digit code means manufacturer’s
identification 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
0204, the tire was produced in the 2nd 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
pressure.
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Technical Data
237
Transmission
Tire Pressures for cold tires 68 °F/20 °CThese tire filling pressures apply only to the tire makes and types approved by Porsche.
fPlease see the chapter “TIRES/WHEELS” on Page 184.
fPlease see the chapter “TPM TIRE PRESSURE MONITORING” on Page 134. 1st gear 3.82
2nd gear 2.26
3rd gear 1.64
4th gear 1.29
5th gear 1.06
6th gear 0.92
Reverse 2.86
Final drive ratio 3.44
Summer tiresfront 29 psi (2.0 bar)
rear 31 psi (2.1 bar)
Snow tiresfront 29 psi (2.0 bar)
rear 35 psi (2.4 bar)
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238
Technical Data
Tires, Rims, Tracks
Tire Rim Rim offset Track
Summer tiresfront 235/35 ZR 19 (87Y) 8.5 J x 19 H2 53 mm 58.9 in./1497 mm
911 GT3 rear 305/30 ZR 19 (102Y) XL 12 J x 19 H2 63 mm 60.0 in./1524 mm
Snow tiresfront 235/35 R 19 87V M+S 8.5 J x 19 H2 53 mm
911 GT3 rear 295/30 R 19 100V XL M+S* 11 J x 19 H2 67 mm
The load capacity coefficient (e.g. “87”) and maximum speed code letter (e.g. “Y”) are minimum requirements.
Snow chainsCan be mounted only on the rear wheels; maximum speed 30 mph (50 km/h).
Use only Porsche authorized fine-link cross-type or edge chains.
Snow chain clearance can be guaranteed only on the tire + rim combination marked*.
Tire and rim sizesExtensive tests are performed before specific tires and wheels are approved by Porsche. Your Porsche dealer has informa-
tion about approved tires and wheels and is happy to assist you.
If aftermarket tires and/or wheels are installed which are not approved by Porsche, the vehicle’s driveability, stability while
in motion and handling characteristics might be impaired. Since Porsche has no data on such combinations, Porsche cannot
stand behind the safety or durability of these aftermarket combinations.
Danger!
Installation of sizes not authorized by
Porsche may have a dangerous effect on
the driving stability and could result in
severe personal injury or death.
fBefore mounting new tires, check with your Porsche dealer about the current release status.
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