122-V7S2D-04

4
911 (991)
Technical Information
05/18
ENU
4400
Approved Wheels and Tires (05/18)
Revision:
This bulletin replaces bulletin Group 4, #4/17, dated June 8, 2017.
Model Year:
As of 2017
Vehicle Type:
911 Carrera (991)/911 Targa (991)/911 Turbo (991)
Concern:
Approval status: January 2018
Sizes:
Permissible tire and wheel sizes
(RO = rim offset in mm, FA = front axle, RA = rear axle)
Tires
Tire sizes
Wheel sizes
Snow
chains
911 Carrera
FA: 235/40 ZR 19 (92Y)
RA: 295/35 ZR 19 (100Y)
Summer
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
FA: 235/40 R 19 92V M+S
RA: 295/35 R 19 100V M+S
Winter
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
FA: 8.5J x 19 H2, RO 50
RA: 11.5J x 19 H2, RO 76
FA: 8.5J x 20 H2, RO 49
RA: 11.5J x 20 H2, RO 76
No
No
No
FA: 8.5J x 19 H2, RO 50
RA: 11J x 19 H2, RO 77
RA only
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 78
RA only
911 Carrera S
Summer
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
FA: 8.5J x 20 H2, RO 49
RA: 11.5J x 20 H2, RO 76
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Mar 7, 2018
Page 1 of 14
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911 (991)
4400
ENU
Technical Information
05/18
Tires
Tire sizes
Wheel sizes
Snow
chains
FA: 8.5J x 19 H2, RO 50
RA: 11J x 19 H2, RO 77
RA only
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 78
RA only
FA: 235/40 R 19 92V M+S
RA: 295/35 R 19 100V M+S
Winter
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
- Not for vehicles with rear axle
steering
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
911 Carrera 4, 911 Targa 4
FA: 235/40 ZR 19 (92Y)
RA: 295/35 ZR 19 (100Y)
Summer
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
FA: 235/40 R 19 92V M+S
RA: 295/35 R 19 100V M+S
Winter
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
FA: 8.5J x 19 H2, RO 50
RA: 11.5J x 19 H2, RO 56
FA: 8.5J x 20 H2, RO 49
RA: 11.5J x 20 H2, RO 56
No
No
No
FA: 8.5J x 19 H2, RO 50
RA: 11J x 19 H2, RO 56
RA only
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 56
RA only
911 Carrera 4S, 911 Targa 4S
Summer
Mar 7, 2018
Page 2 of 14
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
FA: 8.5J x 20 H2, RO 49
RA: 11.5J x 20 H2, RO 56
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No
Tires
4
911 (991)
Technical Information
05/18
Tire sizes
ENU
4400
Wheel sizes
Snow
chains
FA: 8.5J x 19 H2, RO 50
RA: 11J x 19 H2, RO 56
RA only
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 56
RA only
FA: 235/40 R 19 92V M+S
RA: 295/35 R 19 100V M+S
Winter
- Not for vehicles with Porsche
Ceramic Composite Brake (PCCB)
- Not for vehicles with rear axle
steering
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
911 Carrera GTS, 911 Carrera 4 GTS, 911 Targa 4 GTS
Summer
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
Winter
FA: 8.5J x 20 H2, RO 49
RA: 11.5J x 20 H2, RO 56
No
No
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 56
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
RA: 295/30 R 20 101V XL M+S
- Vehicles without central wheel lock
FA: 8.5J x 20 H2, RO 51
RA: 11J x 20 H2, RO 59
RA only
- Vehicles with central wheel lock
911 Turbo, 911 Turbo S
Summer
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
FA: 9J x 20 H2, RO 51
RA: 11.5J x 20 H2, RO 56
No
No
FA: 8.5J x 20 H2, RO 49
RA: 11J x 20 H2, RO 56
- Vehicles without central wheel lock
Winter
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
FA: 8.5J x 20 H2, RO 51
RA: 11J x 20 H2, RO 56
RA only
- Vehicles without central wheel lock
FA: 8.5J x 20 H2, RO 51
RA: 11J x 20 H2, RO 59
- Vehicles with central wheel lock
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Mar 7, 2018
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911 (991)
4400
Wheels:
ENU
Technical Information
05/18
Overview of Porsche wheels for summer and winter tires
Identification on inside of wheel:
Wheel size, rim offset (RO) in mm, part number (without color code FFF) and Porsche logo
19-inch "Carrera 6" wheel
FA: 8.5J x 19 H2, RO 50
Part No. 991.362.510.00_FFF
RA: 11.5J x 19 H2, RO 76
Part No. 991.362.560.00_FFF
RA: 11.5J x 19 H2, RO 56
Part No. 991.362.560.01_FFF
RA: 11J x 19 H2, RO 77
Part No. 991.362.560.02_FFF
RA: 11J x 19 H2, RO 56
Part No. 991.362.560.03_FFF
20-inch "Carrera S4" wheel
FA: 8.5J x 20 H2, RO 49
Part No. 991.362.710.00_FFF
RA: 11.5J x 20 H2, RO 76
Part No. 991.362.760.00_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.760.01_FFF
RA: 11J x 20 H2, RO 78
Part No. 991.362.760.02_FFF
RA: 11J x 20 H2, RO 56
Part No. 991.362.760.03_FFF
Mar 7, 2018
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AfterSales
911 (991)
Technical Information
05/18
ENU
4400
4
20-inch "Carrera Classic II" wheel
FA: 8.5J x 20 H2, RO 49
Part No. 991.362.711.02_FFF
RA: 11.5J x 20 H2, RO 76
Part No. 991.362.761.04_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.761.05_FFF
20-inch "RS Spyder Design" wheel
FA: 8.5J x 20 H2, RO 49
Part No. 991.362.712.00_FFF
RA: 11.5J x 20 H2, RO 76
Part No. 991.362.760.04_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.760.05_FFF
20-inch "Turbo 4" wheel
FA: 8.5J x 20 H2, RO 49
Part No. 991.362.711.00_FFF
FA: 9J x 20 H2, RO 51
Part No. 991.362.720.00_FFF
RA: 11.5J x 20 H2, RO 76
Part No. 991.362.761.00_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.761.01_FFF
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Mar 7, 2018
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911 (991)
4400
ENU
Technical Information
05/18
20-inch "911 Turbo III" wheel
FA: 8.5J x 20 H2, RO 51
Part No. 991.362.161.06_FFF
RA: 11J x 20 H2, RO 56
Part No. 991.362.166.09_FFF
20-inch "911 Sport Classic" wheel
FA: 9J x 20 H2, RO 51
Part No. 991.362.162.41_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.167.42_FFF
20-inch "911 Carrera Sport" wheel
FA: 8.5J x 20 H2, RO 49
Part No. 991.362.722.00_FFF/991.363.722.0
0_FFF
RA: 11.5J x 20 H2, RO 76
Part No. 991.362.772.00
_FFF/991.363.772.00 _FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.772.01
_FFF/991.363.772.01 _FFF
Mar 7, 2018
Page 6 of 14
AfterSales
911 (991)
Technical Information
05/18
ENU
4400
4
20-inch "911 Turbo Sport 3" wheel
FA: 9J x 20 H2, RO 51
Part No. 991.362.721.00_FFF
RA: 11.5J x 20 H2, RO 56
Part No. 991.362.771.00_FFF
20-inch "911 Turbo Sport II" wheel
FA: 8.5J x 20 H2, RO 51
Part No. 991.362.161.34_FFF
RA: 11J x 20 H2, RO 59
Part No. 991.362.166.34_FFF
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.
Information
Only fit wheels with identical part numbers on one axle.
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Mar 7, 2018
Page 7 of 14
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911 (991)
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Wheel
Mounting:
ENU
Technical Information
05/18
using wheel bolts:
Tightening torque 160 Nm (118 ftlb.)
using central wheel lock:
Tightening torque 600 Nm (444 ftlb.)
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.
Summer Tires:
Model
Tire size
FA: 235/40 ZR 19 (92Y)
RA: 295/35 ZR 19 (100Y)
911 Carrera,
911 Carrera 4,
911 Targa 4
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
Tire make and type
Goodyear F1 Eagle Asymmetric 2 N0
(Inside/Outside)
Yokohama Advan Sport V105 N0
(Inside/Outside)
Pirelli P Zero N1
(Inside/Outside)
Pirelli P Zero Corsa N0
(Inside/Outside)
- Ultra High Performance tires
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
911 Carrera S,
911 Carrera 4S,
911 Targa 4S
911 Carrera GTS
911 Carrera 4
GTS
911 Targa 4 GTS
911 Turbo
911 Turbo S
Mar 7, 2018
Page 8 of 14
FA: 245/35 ZR 20 (91Y)
RA: 305/30 ZR 20 (103Y) XL
Michelin Pilot Sport 4S N0
(Rotation)
Pirelli P Zero N1
(Inside/Outside)
Pirelli P Zero Corsa N0
(Inside/Outside)
- Ultra High Performance tires
FA: 245/35 ZR 20 (95Y) XL
RA: 305/30 ZR 20 (103Y) XL
AfterSales
Michelin Pilot Sport 4S N0
(Rotation)
911 (991)
Technical Information
Winter Tires:
Model
911 Carrera,
911 Carrera S,
911 Carrera 4,
911 Carrera 4S,
911 Targa 4
911 Targa 4S
911 Carrera GTS
911 Carrera 4
GTS
911 Targa 4 GTS
911 Turbo
911 Turbo S
05/18
Tire size
ENU
4400
4
Tire make and type
Pirelli Winter 240 Sottozero Series II N0
(Inside/Outside)
FA: 235/40 R 19 92V M+S
RA: 295/35 R 19 100V M+S
Continental WinterContact TS 830P N0
(Inside/Outside)
Pirelli Winter 240 Sottozero Series II N0
(Inside/Outside)
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
Michelin Pilot Alpin PA4 N1
(Rotation)
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 97V M+S
Pirelli Winter 240 Sottozero Series II N0
(Inside/Outside)
FA: 245/35 R 20 91V M+S
RA: 295/30 R 20 101V XL
M+S
Michelin Pilot Alpin PA4 N1
(Inside/Outside)
Arrow with inscription “Rotation”
= directional mounting
“Inside/Outside” inscription or “Left” or “Right”
= mounting on specified side only
Arrow with both inscriptions “Rotation” and
“Inside/Outside”
= directional mounting on specified side only.
Arrow with both inscriptions “Rotation” and “Left”
or “Right”
= directional mounting on specified side only.
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.
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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Mar 7, 2018
Page 9 of 14
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911 (991)
4400
ENU
Technical Information
05/18
Tire Pressure:
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 only tires recommended by Porsche.
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.
Standard tire pressure for summer tires
Wheel
size
Part load
991 Carrera S
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
19-inch
wheels
2.1 bar
210 kPa
30 psi
2.5 bar
250 kPa
36 psi
2.4 bar
240 kPa
34 psi
3.0 bar
300 kPa
43 psi
–
–
–
–
20-inch
wheels
2.2 bar
220 kPa
31 psi
2.6 bar
260 kPa
37 psi
2.4 bar
240 kPa
34 psi
3.1 bar
310 kPa
44 psi
2.2 bar
220 kPa
31 psi
2.6 bar
260 kPa
37 psi
2.4 bar
240 kPa
34 psi
3.1 bar
310 kPa
44 psi
Wheel
size
Mar 7, 2018
Page 10 of 14
911 Carrera
911 Carrera 4, 911 Targa 4
Part load
991 Carrera 4S, 911 Targa 4S
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
19-inch
wheels
2.1 bar
210 kPa
30 psi
2.6 bar
260 kPa
37 psi
2.4 bar
240 kPa
34 psi
3.0 bar
300 kPa
43 psi
–
–
–
–
20-inch
wheels
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
2.4 bar
240 kPa
34 psi
3.1 bar
310 kPa
44 psi
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
2.4 bar
240 kPa
34 psi
3.1 bar
310 kPa
44 psi
AfterSales
20-inch
wheels
05/18
911 Carrera GTS, 911 Carrera 4
GTS, 911 Targa 4 GTS
Wheel
size
4
911 (991)
Technical Information
Part load
4400
ENU
911 Turbo, 911 Turbo S
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
2.4 bar
240 kPa
34 psi
3.1 bar
310 kPa
44 psi
2.4 bar
240 kPa
34 psi
3.0 bar
300 kPa
43 psi
2.6 bar
260 kPa
37 psi
3.3 bar
330 kPa
47 psi
Standard tire pressure for winter tires
Wheel
size
911 Carrera, 911 Carrera S, 911
Carrera 4S, 911 Targa 4, 911 Targa 4S
Part load
911 Carrera GTS, 911 Carrera 4
GTS, 911 Targa 4 GTS
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
19-inch
wheels
2.2 bar
220 kPa
31 psi
2.3 bar
230 kPa
33 psi
2.2 bar
220 kPa
31 psi
2.6 bar
260 kPa
37 psi
–
–
–
–
20-inch
wheels
2.2 bar
220 kPa
31 psi
2.5 bar
250 kPa
36 psi
2.2 bar
220 kPa
31 psi
2.9 bar
290 kPa
42 psi
2.2 bar
220 kPa
31 psi
2.5 bar
250 kPa
36 psi
2.2 bar
220 kPa
31 psi
2.9 bar
290 kPa
42 psi
911 Turbo, 911 Turbo S
Wheel size
20-inch wheels
Part load
Full load
FA
RA
FA
RA
2.2 bar
220 kPa
31 psi
2.5 bar
250 kPa
36 psi
2.2 bar
220 kPa
31 psi
3.0 bar
300 kPa
43 psi
Comfort tire pressure for summer tires up to 165 mph (270 km/h) – only for vehicles with Tire
Pressure Monitoring (TPM) and “Comfort pressure” menu in the multi-function display
WARNING
Driving at high speed with low tire pressure
•
Irreparable damage to tires

Set Comfort air pressure for tires only on vehicles with Tire Pressure Monitoring (TPM) and “Comfort”
selected in the "Tire pressure" main menu in the multi-function display.
AfterSales
Mar 7, 2018
Page 11 of 14
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911 (991)
4400
ENU
Technical Information
05/18
Wheel
size
911 Carrera
Part load
911 Carrera S
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
19-inch
wheels
2.0 bar
200 kPa
29 psi
2.2 bar
220 kPa
31 psi
2.1 bar
210 kPa
30 psi
2.6 bar
260 kPa
37 psi
–
–
–
–
20-inch
wheels
2.0 bar
200 kPa
29 psi
2.2 bar
220 kPa
31 psi
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
2.0 bar
200 kPa
29 psi
2.2 bar
220 kPa
31 psi
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
911 Carrera 4S, 911 Targa 4S,
911 Carrera GTS, 911 Carrera
4 GTS, 911 Targa 4 GTS
911 Carrera 4, 911 Targa 4
Wheel
size
Part load
Full load
Part load
Full load
FA
RA
FA
RA
FA
RA
FA
RA
19-inch
wheels
2.0 bar
200 kPa
29 psi
2.3 bar
230 kPa
33 psi
2.1 bar
210 kPa
30 psi
2.6 bar
260 kPa
37 psi
–
–
–
–
20-inch
wheels
2.0 bar
200 kPa
29 psi
2.3 bar
230 kPa
33 psi
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
2.0 bar
200 kPa
29 psi
2.3 bar
230 kPa
33 psi
2.2 bar
220 kPa
31 psi
2.7 bar
270 kPa
39 psi
911 Turbo, 911 Turbo S
Wheel size
20-inch wheels
Part load
Full load
FA
RA
FA
RA
2.2 bar
220 kPa
31 psi
2.5 bar
250 kPa
36 psi
2.3 bar
230 kPa
33 psi
2.8 bar
280 kPa
40 psi
Snow Chains:
WARNING
Incorrectly installed snow chains
•
Uncontrollable vehicle handling

Do not exceed the maximum speed of Speed 30 mph/50 km/h.

Observe installation instructions from the chain manufacturer.
Porsche offers the following snow chains as accessories:
Mar 7, 2018
Page 12 of 14
AfterSales
911 (991)
Technical Information
Tire size
295/35 R 19 M+S
295/30 R 20 M+S
05/18
ENU
4400
Porsche Part No.
Type of snow chain
991.044.600.00
Link-type chain, quick fit
4
Wheel Storage: 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.
Complete wheels can be stacked for storage; it is advisable to increase the tire pressure by approx. 6 psi
(0.4 bar).
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.
General
Information:
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. Refer to notes on page 1 (if applicable).
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.
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.
If new tires are to be mounted or the tires of one axle are to be replaced, tires of the same make, the
same 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 by more than 30 %.
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.
AfterSales
Mar 7, 2018
Page 13 of 14
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911 (991)
4400
ENU
Technical Information
05/18
Repairs on “ZR” tires are not permissible, as is the use of inner tubes in tubeless tires. Tires age due
to chemical and physical processes, which can impair their function. 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.
© 2018 Porsche Cars North America, Inc.
Mar 7, 2018
Page 14 of 14
AfterSales