No. 64-20

911 (996)
Manufacturer's Certificate
64/20
ENU
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Approved Tires, Wheels and Spacers (64/20)
Revision:
This bulletin replaces bulletin Group 4 06/11, dated May 26, 2011.
Model Year:
As of 1998 up to 2005
Vehicle Types:
911 Carrera / Carrera 4 / Targa (996)
Information:
Approved tires
WARNING
Driving with different tires (mixed tires)
•
Uncontrollable vehicle handling

Only use tires of the same make and type, with the same speed index and the same specification code
(N0, N1, N2, ...) on a vehicle.
Makes/Types:
Summer tire approvals
Tire size
Tire make and type /
Label value (Link to EU database)
Comments
Pirelli P Zero Rosso Asimmetrico N5
FA: https://eprel.ec.europa.eu/qr/596142
RA: https://eprel.ec.europa.eu/qr/596140
Bridgestone Potenza S-02A N4
FA/RA: Label values currently not available
Continental ContiSportContact2 N2
205/50 ZR17 (FA)
255/40 ZR17 (RA)
FA/RA: Label values currently not available
Michelin Pilot Sport 2 N3
996 C2, 996 C4, 996
Targa
up to MY 01
FA: https://eprel.ec.europa.eu/qr/409007
RA: https://eprel.ec.europa.eu/qr/412056
Pirelli P Zero Trofeo R N0 (Ultra High
Performance tires)
FA: https://eprel.ec.europa.eu/qr/621935
RA: https://eprel.ec.europa.eu/qr/621934
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Pirelli P Zero Rosso Asimmetrico N4
FA: Label values currently not available
RA: https://eprel.ec.europa.eu/qr/595111
Bridgestone Potenza S-02A N3
FA/RA: Label values currently not available
Continental ContiSportContact2 N2
225/40 ZR18 (FA)
265/35 ZR18 (RA)
FA/RA: Label values currently not available
Michelin Pilot Sport 2 N3
996 C2, 996 C4, 996
Targa
up to MY 01
FA: https://eprel.ec.europa.eu/qr/411351
RA: https://eprel.ec.europa.eu/qr/412881
Pirelli P Zero Trofeo R N0 (Ultra High
Performance tires)
FA: https://eprel.ec.europa.eu/qr/621936
RA: https://eprel.ec.europa.eu/qr/621937
Pirelli P Zero Rosso Asimmetrico N4
FA: Label values currently not available
RA: https://eprel.ec.europa.eu/qr/595112
Bridgestone Potenza S-02A N3
225/40 ZR18 (FA)
285/30 ZR18 (RA)
FA/RA: Label values currently not available
Continental ContiSportContact N2
996 C2, 996 C4, 996
Targa
from MY 02
FA/RA: Label values currently not available
Michelin Pilot Sport 2 N3
FA: https://eprel.ec.europa.eu/qr/411351
RA: https://eprel.ec.europa.eu/qr/408435
Information
N... = Specification code of the tire, e.g. "N0", "N1", "N2" ... The complete "N ..." code of the tires in
question must be shown on the tire sidewall near the tire type designation.
Instructions for correct mounting of the tires are also given on the tire sidewall. If there are no mounting
instructions on the tire sidewall, the tire must be mounted so that the DOT marking is visible from the
outside.
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911 (996)
Manufacturer's Certificate
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Arrow with inscription
“Rotation”
= directional mounting
"Inside/Outside" inscription
= mounting on specified side only
Arrow with both
inscriptions “Rotation” and
“Inside/Outside”
= directional mounting on specified side only
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Information
If a tire is damaged and it is not possible to determine with absolute certainty that there is no ply damage
- with all of its consequences - or if the tire was thermally and/or mechanically overloaded due to a loss of
pressure or other prior damage, replace the tire in question for safety reasons.
Repairs to "V", "W", "Y" and "ZR" tires are not permissable, as well as the use of inner tubes in tubeless
tires. Please inform your customers accordingly. It is advisable to mount winter tires at temperatures
below 45° F/7°C , because the driving characteristics of summer tires are reduced at low temperatures.
Extremely low temperatures can cause permanent damage to summer tires.
WARNING
Incorrect tire pressure
•
Uncontrollable vehicle handling

Adjust the tire pressure according to specifications. Never allow the pressure to fall below the minimum
pressure.

Check age of tires. Replace tires that are more than 6 years old.

Perform visual inspections.

Use new rubber valves at every tire change.

Use only tires approved by Porsche.
Tire Pressure:
17-inch wheels
18-inch wheels
Spare
wheel/collapsible
wheel
Front axle
2.5 bar (36 psi)
2.5 bar (36 psi)
4.2/2.5 bar (61/36
psi)
Rear axle
2.5 bar (36 psi)
3.0 bar (44 psi)
4.2/2.5 bar (61/36
psi)
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Information
The tire pressure applies only to the tire makes and types approved by Porsche, and is specified for cold
tires (approx. 68° F/20°C ). The tire pressures must never be lower than the specified values.
Wheel
Mounting:
The tightening torque for securing wheels and spacers is 130 Nm (96 ftlb.).
Sizes:
Permissible summer tire and wheel sizes (RO = rim offset in mm)
Tires
Wheels
205/50 ZR17 (FA)
7Jx17 RO 55 (FA)
255/40 ZR17 (RA)
9Jx17 RO 55 (RA)
205/50 ZR17 (FA)
7Jx17 RO 55 (FA)
255/40 ZR17 (RA)
9Jx17 RO 55 (RA)
205/50 ZR17 (FA)
7Jx17 RO 55 (FA)
255/40 ZR17 (RA)
9Jx17 RO 55 (RA)
225/40 ZR18 (FA)
7.5Jx18 RO 50 (FA)
265/35 ZR18 (RA)
10Jx18 RO 65 (RA)
Comments
5-mm wheel spacer permitted
on each wheel on the front
and rear axle, Part No.
996.361.605.00 , 2 , 3 :
17-mm thick spacer per wheel
on the rear axle is permitted,
Part No. 996.361.617.00, ,
1 , 3 ;Snow chains cannot be
installed 17 mm thick spacers
on each wheel on the rear axle;
Part No. 996.361.617.00 ,
1 , 3 ; Snow chains cannot
be installed
Only for vehicles up to and
including model year 2001
Snow chains cannot be installed
Only for vehicles up to and
including model year 2001
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225/40 ZR18 (FA)
7.5Jx18 RO 50 (FA)
265/35 ZR18 (RA)
10Jx18 RO 65 (RA)
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5-mm wheel spacer permitted
on each wheel on the front
and rear axle, Part No.
996.361.605.00 , 2 , 3 ; Snow
chains cannot be installed
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Only for vehicles up to and
including model year 2001
225/40 ZR18 (FA)
7.5Jx18 RO 50 (FA)
265/35 ZR18 (RA)
10Jx18 RO 65 (RA)
225/40 ZR18 (FA)
8Jx18 RO 50/52 (FA) 2
285/30 ZR18 (RA) 2 4
10Jx18 RO 65 (RA)
225/40 ZR18 (FA)
8Jx18 RO 50/52 (FA) 2
285/30 ZR18 (RA) 2 4
10Jx18 RO 65 (RA)
225/40 ZR18 (FA)
8Jx18 RO 50/52 (FA)
285/30 ZR18 (RA) 2 4 5
11Jx18 RO 63 (RA)
225/40 ZR18 (FA)
8Jx18 RO 50/52 (FA)
295/30 ZR18 (RA) 2 4 5
11Jx18 RO 63 (RA)
17-mm wheel spacer permitted
on each wheel on the rear axle,
Part No. 996.361.617.00 ,
1 , 2 , 4 ; Snow chains cannot
be installed
Snow chains cannot be installed
5-mm wheel spacer permitted
on each wheel on the front
and rear axle, Part No.
996.361.605.00 , 2 , 4 ;
Snow chains cannot be installed
Snow chains cannot be installed
Snow chains cannot be installed
1
The spacer must be removed when installing the spare wheel
2
For vehicles up to and including model year 2001: Only for European Union (EU) countries.
3
Only in conjunction with the longer wheel bolts used on the 911 GT3, Part No. 996.361.203.90. The
spacer must remain on the vehicle when mounting the spare wheel.
4
The wing seam and if necessary the rear apron on vehicles up to and including model year 2001
require subsequent work.
5
For vehicles up to and including model year 2001
Further detailed information about permitted wheel and tire sizes as well as spacers that may be required
can be found in the relevant parts certificates/manufacturer’s certificates held by the Porsche partners.
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Makes/Types:
Winter tire approval
Tire size
205/50 R17 93V XL
M+S (FA)
Tire make and type /
Label value (Link to EU database)
Pirelli Winter Sottozero 3 N2
FA: https://eprel.ec.europa.eu/qr/595707
255/40 R17 98V XL
M+S (RA)
RA: https://eprel.ec.europa.eu/qr/595709
225/40 R18 92V XL
M+S (FA)
Pirelli Winter Sottozero 3 N4
265/35 R18 97V XL
M+S (RA)
Snow chain
clearance
(only without
spacers)
FA: https://eprel.ec.europa.eu/qr/595710
Yes
No
RA: https://eprel.ec.europa.eu/qr/621928
Information
N... = Specification code of the tire, e.g. "N0", "N1", "N2" ... The complete "N ..." code of the tires in
question must be shown on the tire sidewall near the tire type designation.
Instructions for correct mounting of the tires are also given on the tire sidewall. If there are no mounting
instructions on the tire sidewall, the tire must be mounted so that the DOT marking is visible from the
outside.
Speed index: V = 240 km/h
Arrow with inscription
“Rotation”
= directional mounting
"Inside/Outside" inscription
= mounting on specified side only
Arrow with both
inscriptions “Rotation” and
“Inside/Outside”
= directional mounting on specified side only
Information
If a tire is damaged and it is not possible to determine with absolute certainty that there is no ply damage
- with all of its consequences - or if the tire was thermally and/or mechanically overloaded due to a loss of
pressure or other prior damage, replace the tire in question for safety reasons.
Repairs to "V", "W", "Y" and "ZR" tires are not permissable, as well as the use of inner tubes in tubeless
tires. Please inform your customers accordingly. It is advisable to mount winter tires at temperatures
below 45° F/7°C , because the driving characteristics of summer tires are reduced at low temperatures.
Extremely low temperatures can cause permanent damage to summer tires.
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911 (996)
Manufacturer's Certificate
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WARNING
Incorrect tire pressure
•
Uncontrollable vehicle handling

Adjust the tire pressure according to specifications. Never allow the pressure to fall below the minimum
pressure.

Check age of tires. Replace tires that are more than 6 years old.

Perform visual inspections.

Use new rubber valves at every tire change.

Use only tires approved by Porsche.
Tire Pressure:
17-inch wheels
18-inch wheels
Front axle
2.5 bar (36 psi)
2.5 bar (36 psi)
Rear axle255/40 R 17)
2.5 bar (36 psi)
Rear axle225/45 R 17
2.8 bar (41 psi)
3.0 bar (44 psi)
Information
The tire pressure applies only to the tire makes and types approved by Porsche, and is specified for cold
tires (approx. 68° F/20°C ). The tire pressures must never be lower than the specified values.
Wheel
Mounting:
The tightening torque for securing wheels and spacers is 130 Nm (96 ftlb.).
Sizes:
Permissible winter tire and wheel sizes (RO = rim offset in mm)
Tires
Wheels
Comments
7Jx17 RO 55/50 (FA)
Part number of the snow chain
996.361.921.00
9Jx17 RO 55 (RA)
7Jx17 RO 55/50 (FA)
205/50 R17 93V XL M+S (FA)
9Jx17 RO 55 (RA)
Spacer ring of 5 mm on front
and rear axle permitted, Part
No. 996.361.605.90 6 7
Snow chains cannot be installed
255/40 R17 98V XL M+S (RA)
7Jx17 RO 55/50 (FA)
9Jx17 RO 55 (RA)
Spacer ring of 17 mm on front
and rear axle permitted, Part
No. 996.361.617.006 8 9
Snow chains cannot be installed
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7.5Jx18 RO 50 (FA)
10Jx18 RO 65 (RA)
7.5Jx18 RO 50 (FA)
225/40 R18 92V XL M+S (FA)
10Jx18 RO 65 (RA)
Snow chains cannot be installed
Spacer ring of 5 mm on front
and rear axle permitted, Part
No. 996.361.605.90 6 7
Snow chains cannot be installed
265/35 R18 97V XL M+S (RA)
7.5Jx18 RO 50 (FA)
10Jx18 RO 65 (RA)
Spacer ring of 17 mm on front
and rear axle permitted, Part
No. 996.361.617.006 8 9
Snow chains cannot be installed
8Jx18 RO 50/52 (FA)
10Jx18 RO 65 (RA)
8Jx18 RO 50/52 (FA)
225/40 R18 92V XL M+S (FA)
10Jx18 RO 65 (RA)
Snow chains cannot be installed
Spacer ring of 5 mm on front
and rear axle permitted, Part
No. 996.361.605.90 6 7
Snow chains cannot be installed
265/35 R18 97V XL M+S (RA)
8Jx18 RO 50/52 (FA)
10Jx18 RO 65 (RA)
Spacer ring of 17 mm on front
and rear axle permitted, Part
No. 996.361.617.006 8 9
Snow chains cannot be installed
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6
The spacer must be removed when installing the spare wheel
7
For vehicles up to and including model year 2001: Only for European Union (EU) countries.
8
Only in conjunction with the longer wheel bolts used on the 911 GT3, Part No. 996.361.203.90. The
spacer must remain on the vehicle when mounting the spare wheel.
9
The wing seam and if necessary the rear apron on vehicles up to and including model year 2001
require subsequent work.
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911 (996)
Manufacturer's Certificate
Subsequent
installation of
spacers
64/20
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Securing spacers and wheels
The 5-mm thick spacers are secured on the
wheel hubs together with the brake discs
using countersunk screws (M6x16), Part No.
900.269.106.09.
Tightening torque 10 Nm (7.5 ftlb.)
The 5-mm spacer must remain on the vehicle
when mounting the spare wheel.
5-mm spacer
If 5-mm spacers are used, the wheels must be
secured using the 5-mm longer wheel bolts used
on the 911 GT3, Part No. 996.361.980.00.
These wheel bolts are marked with GT or with a
red color on the front of the bolt head (arrow) or
the rotating spherical cap is galvanized in red.
Length “X” approx. 50 mm
Tightening torque 130 Nm (96 ftlb.)
If the spacer is removed, the original wheel bolts,
Length “X” approx. 45 mm, must be used
again.
The 17-mm spacer rings are mounted on the
wheel hubs using the standard wheel bolts, Part
No. 996.361.203.00 (dimension X = approx. 45
mm). Tightening torque: 130 Nm (96 ftlb.).
Wheel bolt
The wheels are mounted on the 17-mm
spacer rings using wheel nuts. Part No.
999.182.003.36. Tightening torque: 130 Nm
(96 ftlb.).
The 17-mm spacer ring must be removed
when mounting the spare wheel.
Wheel
mounting:
The tightening torque for securing wheels and spacers is 130 Nm (96 ftlb.).
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Reworking wing
seam (only
required for
vehicles up to
model year
2001):
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64/20
The wing seam and rear spoiler, if necessary,
must be reworked in the area shown:
A = transition approx. 50 mm
B = flange approx. 295 mm
C = transition approx. 25 mm
The wing seam must be flanged over a width of at
least 10 mm and at least 60°; never flange, grind
or cut off more than 65°.
Adapting the
rear apron:
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If the rear apron projects beyond the flanged
rear side section (cut-out A), cut or grind off the
projecting part of the rear apron (arrow).
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Wheels:
Information
Improper handling can damage the wheel surface.
Carry out tire removal and mounting using a bead holding-down device only.
Use a leather pad on the rim flange to support the valve insertion tool.
Only use the Porsche centering clamping set for balancing.
Do not use brushes to clean the wheels because brushes can cause deep scratches that cannot be
removed by polishing.
Never use solvents or other chemical substances on tires.
Overview of Porsche wheels
Identification on the inside/outside of the wheel disc:
Wheel size, rim offset (RO) in mm, Part No. and Porsche logo
FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
17-inch Carrera wheel
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FA: 7 J x 17 AH, RO 55
RA: 9 J x 17 AH, RO 55
17-inch Cup Design wheel
FA: 7 J x 17 AH, RO 55
RA: 8.5J x 17 AH, RO 50
Only for winter
17-inch Dyno wheel
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FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
17-inch Targa wheel
FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
17-inch SportClassic wheel
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FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
Only for summer
17-inch 993 Cup Design wheel
FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
17-inch Carrera 4 wheel
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FA: 7 J x 17 H2, RO 55
RA: 9 J x 17 H2, RO 55
Only for winter
17-inch Carrera II wheel
FA: 7 J x 17 H2, RO 55
RA: 8.5J x 17 H2, RO 50
Only for winter
17-inch Boxster S wheel
FA: 7.5 J x 18 H2, RO 50
RA: 10J x 18 H2, RO 65
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FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 52
RA: 10 J x 18 H2, RO 65
18-inch SportClassic II wheel
FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 52
10 J x 18 H2, RO 65
18-inch SportDesign wheel
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FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 52
RA: 10 J x 18 H2, RO 65
18-inch Turbo I wheel
FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 50
RA: 10 J x 18 H2, RO 65
Only for winter
18-inch Carrera II wheel
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7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 50
10 J x 18 H2, RO 65
Only for summer
18-inch Carrera wheel
FA: 8 J x 18 H2, RO 50
RA: 10 J x 18 H2, RO 65
Only for summer
18-inch Carrera wheel
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FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2, RO 52
RA: 10 J x 18 H2, RO 65
Only for summer
18-inch Turbo Look I wheel
FA: 7.5 J x 18 H2, RO 50
or FA: 8 J x 18 H2 RO 52
RA: 10 J x 18 H2 RO 65
Only for summer
18-inch Turbo Look I high-gloss wheel
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FA: (winter only) 7.5J x 18 H2, RO 50
FA: 8 J x 18 H2, RO 50
RA: 10 J x 18 H2, RO 65
18-inch Turbo Look II wheel
FA: 8J x 18 H2, RO 50/52
RA: 11 J x 18 H2, RO 63
Navigation
systems:
After a wheel change, the full locating accuracy is attained only after a trip of approx. 50 km (30
miles), if possible on a motorway and at a speed > 60 km/h (40 mph). Additionally, a high wheel slip
factor (e.g. wheel spin) can result in temporary incorrect positioning.
Wheel Storage: •
•
•
•
•
•
•
•
General
Information:
•
•
•
•
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Tires must be stored in a cool, dry and dark room with adequate ventilation.
Tires must never come into contact with fuel, oil, grease or chemicals.
Do not store summer tires in storage areas with ambient temperatures of less than 5° F (-15° C).
Complete wheel & tire assemblies can be stacked for storage; we recommend that you increase the
tire pressure by approximately 6 psi (0.4 bar).
Optimum conditions for storage of the complete wheels are provided by the Original Porsche
storage trolley, Part No. 000.044.000.38.
If the tires are not mounted on wheels, it is best to store them in a vertical position.
We recommend that you turn tires stored in this position every two weeks in order to prevent flat
spots.
Tires that are stacked in a horizontal position will become severely deformed and cannot be seated
properly in the rim flange when they are mounted.
Always use new valves when changing tires.
Always observe any possible instructions concerning the rolling direction and/or specifying which
side the tires must be mounted on.
Coat the tire beads and humps with mounting lubricant before mounting the tire. This ensures that
the tire beads will slide over the humps easily.
In order to prevent the tire from turning on the wheel, avoid extreme driving maneuvers (acceleration
and braking) during the first 100 to 200 miles with new or recently mounted tires.
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In order to optimize smoothness of rolling, it is appropriate - and necessary in individual cases - to
mount the tire in a certain (favorable) position with respect to the wheel (matching).
Matching (uncontrolled and controlled) is explained below: Uncontrolled matching:
•
Turning the tire on the wheel by 90° or 120° if necessary in order to achieve an acceptable value with
regard to rolling smoothness (true running, imbalance and weight distribution of balance weights).
Controlled matching:
•
•
•
With a balancing machine with matching program. In most cases, this produces an even better result
with regard to the rolling smoothness (true running, imbalance and weight distribution of the balance
weights) than can be achieved with uncontrolled matching.
Maximum permissible radial runout and lateral runout of the wheels < 0.7 mm. Maximum
permissible radial runout and lateral runout of the wheels with tires < 1.25 mm. Values < 1.50 mm
-ideally approx. 0.5 mm - are desirable.
The mounting pressure (seating pressure) of 58 psi/4.0 bar overpressure must not be exceeded
before both tire beads are evenly seated on the rim flange.
New Tires (Replacements):
•
•
•
•
If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make,
type and with the same specification code must always be used on each of the two axles.
If tires are replaced on one axle only, the different tread depth from that on the other axle can cause a
noticeable change in the familiar handling.
This is especially the case if new tires are mounted on the rear axle.
This effect decreases with increasing tire mileage.
When replacing a tire on an axle, make sure that the tread depth of the new tire does not differ from that of
the other tire on the same axle by more than 30 %.
Refer to WM 449503 for specific details of the vehicle you are working on.
•
•
>The 2mm specification will be given here.
> If there is none listed then the default is 30%.
Repairs to Tires:
•
•
If a tire is damaged and it cannot be determined with absolute certainty that there is no ply damage
- with all of its consequences - or if the tire was thermally or mechanically overloaded due to a loss
of pressure or other prior damage, we recommend replacement of the tire in question for safety
reasons.
Repairs to "V", "W", "Y", and "ZR" tires are not permissible, as is the use of inner tubes in tubeless
tires.
Tire Aging:
•
Tires age due to chemical and physical processes, which can impair their function.
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•
•
•
•
•
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Tires that are stored unused for an extended period harden and become brittle faster than tires that
are in continual use.
Hairline aging cracks can occur on older tires.
On tires in continual use, the kneading action activates the plasticizer in the rubber and thereby
prevents hardening and cracking.
Therefore, attention should be paid not only to the tread depth but also to the age of the tire.
Tires should not be older than 6 years.
The age of the tire can be determined via the DOT code on the sidewall, which indicates the
production date of the tire: e.g. DOT 2201= 22nd week of 2001.
Important Notice: Technical Bulletins issued by Porsche Cars North America, Inc. are intended only for use by professional automotive technicians who have attended Porsche service training
courses. They are written to inform those technicians of conditions that may occur on some Porsche vehicles, or to provide information that could assist in the proper servicing of a vehicle. Porsche special
tools may be necessary in order to perform certain operations identified in these bulletins. Use of tools and procedures other than those Porsche recommends in these bulletins may be detrimental to the
safe operation of your vehicle, and may endanger the people working on it. Properly trained Porsche technicians have the equipment, tools, safety instructions, and know-how to do the job properly and
safely. Part numbers listed in these bulletins are for reference only. The work procedures updated electronically in the Porsche PIWIS diagnostic and testing device take precedence and, in the event of a
discrepancy, the work procedures in the PIWIS Tester are the ones that must be followed.
© 2021 Porsche Cars North America, Inc.
Jul 30, 2021
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AfterSales