No. 32-21 Service Bulletin/Repair Instructions

911 (991)
Manufacturer's Certificate
32/21
ENU
4400
4
Approved Wheels and Tires (32/21)
Revision:
This bulletin replaces bulletin Group 23/18, dated November 19, 2018.
Model Year:
As of 2014 up to 2016
Vehicle Type:
911 Turbo (991)/911 Turbo S (991)
Information:
Approval status: May 2021
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
Tire make and type/

label value (link to EU database)
911 Turbo,

911 Turbo S
245/35 ZR 20 (91Y) XL

and

305/30 ZR 20 (103Y)

XL
Pirelli P-Zero N1

(Inside/Outside)
245/35 ZR 20 (95Y)

and

305/30 ZR 20 (103Y)

XL
Michelin Pilot Sport 4S N0

(Inside/Outside)
FA: https://eprel.ec.europa.eu/qr/595261

RA: https://eprel.ec.europa.eu/qr/595262
FA: https://eprel.ec.europa.eu/qr/411317

RA: https://eprel.ec.europa.eu/qr/408604
WARNING

Driving with sports tires

•
Aquaplaning on wet or muddy roads

Reduce speed.

Drive according to the road conditions.
AfterSales
Jun 17, 2021

Page 1 of 9
4
911 (991)

4400
Summer Tires

(UHP):
ENU
Manufacturer's Certificate
32/21
Model
Tire size
Tire make and type/

label value (link to EU database)
911 Turbo,

911 Turbo S
245/35 ZR 20 (91Y)

and

305/30 ZR 20 (103Y)

XL
Dunlop Sport Maxx Race N0

(Inside/Outside)

FA/RA: Data currently not available

Pirelli P Zero Corsa N0

(Inside/Outside)

FA: https://eprel.ec.europa.eu/qr/595261

RA: https://eprel.ec.europa.eu/qr/595262
Information

Sports tires (Ultra High Performance Tires) are permitted on public roads and satisfy all legal

requirements and road safety criteria.

These tires are also designed for use on racing circuits (driving safety training courses, sports driving

schools, Clubsport events) and offer distinct advantages with regard to dry adhesion and wear-and-tear

compared to normal road tires.

The main features are a reduced tread depth as well as a special thread design and substructure.
Winter Tires:
Model
Tire size
Tire make and type/

label value (link to EU database)
911 Turbo,

911 Turbo S
245/35 R 20 91V

M+S and

295/30 R 20

101V M+S
Michelin Pilot Alpin PA4 N0

(Rotation)

FA: https://eprel.ec.europa.eu/qr/412844

RA: https://eprel.ec.europa.eu/qr/411498

Pirelli Winter 240 Sottozero Serie II N0

(Inside/Outside)

FA: https://eprel.ec.europa.eu/qr/594297

RA: https://eprel.ec.europa.eu/qr/594293
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.
Jun 17, 2021

Page 2 of 9
AfterSales
911 (991)
Manufacturer's Certificate
32/21
ENU
4400
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.
4
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 only tires recommended by Porsche.

WARNING
Driving at high speed with low tire pressure can cause irreparable damage to tires.


Set Comfort air pressure for tires only on vehicles with Tire Pressure Monitoring System (TPMS) and

“Comfort” selected in the "Tire pressure" main menu in the multi-function display.
Tire Pressure:

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.
AfterSales
Jun 17, 2021

Page 3 of 9
4
911 (991)

4400
ENU
Manufacturer's Certificate
32/21
Standard tire pressure for summer tires

Part load

Wheel size

20-inch wheels
Full load
FA
RA
FA
RA
2.4 bar

(34 psi)
3.0 bar

(43 psi)
2.6 bar

(37 psi)
3.3 bar

(47 psi)
Standard tire pressure for winter tires

Part load

Wheel size

20-inch wheels
Full load
FA
RA
FA
RA
2.2 bar

(31 psi)
2.7 bar

(39 psi)
2.4 bar

(34 psi)
3.0 bar

(43 psi)
Comfort tire pressure for summer tires up to 270 km/h (165 mph) – only for vehicles with

Tire Pressure Monitoring (TPM) and “Comfort pressure” menu in the multi-function display

(depending on the country)

Part load

Wheel size

20-inch wheels

Sizes:
Full load
FA
RA
FA
RA
2.2 bar

(31 psi)
2.5 bar

(36 psi)
2.3 bar

(33 psi)
2.8 bar

(40 psi)
Permissible wheel and tire sizes

(RO = rim offset in mm, FA = front axle, RA = rear axle)

Tires
Tire sizes
Wheel sizes
Snow

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