2009 PORSCHE BOXSTER inflation pressure

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Practical Tips, Emergency Service
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 fr om the norm due to var-
iations in driving habits, service practices and dif-
ferences in road characteristics and climate.
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 ar e A (the highest), B and
C, representing the tire’s resistance to the gener-
ation of heat and its abilit y to dissipate heat when
tested under controlled conditions on a specified
indoor laboratory test wheel.
Sustained high temperatur es 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 Vehi
cle 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, result-
ing in serious personal injury or death. Tire pressures
Warning!
Incorrect tire pressure causes increased tire
wear and adversely affects road handling.
This could lead to tire fa ilure, resulting in loss
of control, leading to serious personal injury
or death.
f Always use an accurate tire pressure gage
when checking inflation pressures.
f Do not exceed the maximum tire pressure list-
ed on the tire sidewall.
Please see the chapter “TIRE PRESSURE PLA-
TE” on Page 275. f
Cold tire inflation pressure means: all tires
must be cold, ambient temperature maximum
(68 °F/20 °C)
, when adjusting the inflation
pressure.
Avoid sunlight striking the tires before measur-
ing cold pressures, since the pressures would
rise from temperature influence.
f Valve caps protect the valve from dust and dirt,
and thus from leakage.
Always screw caps tightly down.
Replace missing caps immediately.
f Use only plastic valve caps.
f Do not use commercially available sealant or
tire inflating bottles. Only use Porsche
approved tire sealant.
f Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.

Practical Tips, Emergency Service
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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 147.
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 234.
f Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.
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.

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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.

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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 276.
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.