2009 PORSCHE BOXSTER tires

228
Practical Tips, Emergency Service
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.
f Check tires – including sidewalls – regularly for
foreign bodies, nicks, cuts, cracks and bulges.
f After driving off road, examine tires for signs
of damage such as cuts, tears, bulges or for-
eign objects stuck in the tread. Replace a dam-
aged tire if necessary.
f Cross curb edges slowly and at right angles if
possible.
Avoid driving over steep or sharp curbs.
f In cases of doubt, have the wheel (particularly
the inner side) checked by an authorized Porsche dealer.
Tire replacements If in doubt, contact your 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 re-
placed. However, this condition disappears as the
new tires are broken in.
f
Please adjust your driving style accordingly.
Installation of new tires sh ould only be done by a
qualified tire technician.
Valves
Rubber valve stems must be replaced every time
a tire is replaced.
For metal valves, the installation and replacement
instructions must be observed.
f Use only genuine Porsche metal valves.
f Protect the valve inserts against soiling with
valve caps.
Soiled valve inserts can cause a gradual loss
of air.
f Use only plastic valve caps.

Practical Tips, Emergency Service
229
Parking at the curb
Warning!
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.
f If you are in doubt, have the wheel checked by
an expert, particularly if you suspect damage
on the inside.
f If 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 weight s 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 au-
thorized 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 reme died, you might lose
control of your vehicle which could cause se-
rious personal injury or death.
f Stop the vehicle and check the tires.
f If 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.
f Check this with your authorized Porsche
dealer.Removing and storing tires fAfter changing, adjust tire pressure and torque
wheel bolts diagonally to 94 ftlb (130 Nm).
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 perform-
ance are immune to the effects of storage and
age is unfounded.
Chemical additives, whic h make the rubber elas-
tic, lose their effectivene ss in the course of time
and the rubber becomes brittle and cracks.
Therefore, the tires should be inspected from
time to time.

230
Practical Tips, Emergency Service
Note
Under no circumstances sh
ould 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 four num-
bers read 1208, then the ti re was produced in the
12th week of 2008.
f Store tires in a cool and dry place.
Snow tires For a better grip on snow and ice, use radial M+S
tires with studs.
Check with your local Motor Vehicle Bureau for
possible restrictions.
Danger!
Risk of loss of control and damage to the
vehicle as well as seri ous personal injury or
death.
The standard tires prof ile and rubber mixture
are optimized for wet and dry driving condi-
tions, and may not prove favorable for snow
conditions.
f Therefore install M+S tires before driving in such conditions. Before mounting snow tires, consult with
your Porsche dealer. He has the technical
information necessary to advise you on
wheel and tire compatibility.
Snow tires should have the same load capacity as
original equipment tires and should be mounted on
all four wheels.
Snow tires with studs should be run at moderate
speeds when new in order to give the studs time
to settle.
Danger!
Tires with badly worn treads and studs are
very dangerous and could cause accidents
resulting in serious personal injuries or
death.
f Make sure they are replaced immediately.
f Do not drive a vehicle equipped with snow tires
at prolonged high speed.
Snow tires do not have the same degree of
traction on dry, wet or snowfree roads as a
normal tire.
Furthermore, snow tires wear rapidly under
these conditions.
Comply with all state and local laws
governing snow tire and tread depth
requirements.
Danger!
Risk of accident and se rious personal injury
or death due to excessive speed.
f Always check the maximum speed rating on
the tire sidewall on any tire on the vehicle.
f Never exceed the maximum speed rating of the tires.
f Fit 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).

Practical Tips, Emergency Service
231
Snow chains
Caution!
Risk of damage to body, axle or brake com-
ponents.
f Fit 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.
f Follow instructions issued by the supplier of the chains.
Different states and countries have varying statu-
tory requirements regarding maximum speed.
Check with local authorities for possible restric-
tions.
f Remove chains as soon as the roads are free
of ice and snow. Fitting snow chains
The use of snow chains is not permitted when
5 mm spacers are mounted.
Caution!
Risk of damage to the wheel housings if the
5 mm spacers are not removed before fitting
snow chains.
f To permit the fitting of snow chains, have the 5 mm spacers removed on all 4 wheels.
f To fit/remove the spacers:
Please consult an authorized Porsche dealer.
f Please see the chapter “SPACERS” on
Page 243.
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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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.

Practical Tips, Emergency Service
233
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 per-
missible 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.
f
Please 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
f The rim width in inches A and the rim offset F
are visible from the outside.
The information is inscri bed on the back of the
spokes near the tire valve.
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) as for
Y tires. Speeds of more than
300 km/h (186 mph) are also
possible at a maximum tire load
capacity of 85 % (confirmation from
tire manufacturer required for
speeds of more than 186 mph (300
km/h)).

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Practical Tips, Emergency Service
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.

238
Practical Tips, Emergency Service
Screw in two assembly aids for
cars
with Porsche
Ceramic Composite Brake
10.Take the wheel off and put a new wheel on.
Please see the chapter “WHEEL BOLTS” on
Page 236.
11.Insert wheel bolts and tighten by hand.
12.Remove assembly aids, screw in remaining wheel bolts.
Initially tighten bolts only slightly in diagonally
opposite sequence so that the wheel
is centred.
13.Inflate the tire if necessary. Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.
14.Lower the car fully and remove the jack.
15.Tighten wheel bolts in diagonally opposite sequence.
f Immediately after changing a wheel, use
a torque wrench to check the prescribed
tightening torque (96 ftlb./130 Nm).
Note on operation for vehicles with Tire Pressure
Monitoring
f On vehicles with Tire Pressure Monitoring, the
settings on the on-board computer must be
updated after the wheel change.
f Please see the chapter “TPM TIRE PRESSURE
MONITORING” on Page 147.
Checking tire pressure with a
pressure gage1. Remove the valve stem cap from the tire.
2. Press the pressure gage onto the valve stem.
Note on operation
fDo not press too hard or force the valve stem
sideways, or air will escape.
If the sound of air escaping from the tire is
heard, reposition the pressure gage.
3. Read the tire pressure on the gage stem and compare it to the permissble tire pressure.
This information can be found on the tire pres-
sure plate or in the chapter Technical Data.
Please see the chapter “TIRE PRESSURE FOR
COLD TIRES (68 °F/20 °C)” on Page 277.
4. Remove the pressure gage.
f Please see the chapter “TPM TIRE PRESSURE
MONITORING” on Page 147.