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Porsche // 991 (911) MK1 2012-2016 // 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
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Lock nut for transmission main shaft. Porsche 911 72-89 / 964 / 993 / 996 turbo / 997 turbo / GT3 - 99903403300
99903403300
Vehicle Group
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
- Porsche 911 1974-1977 2.7L / 1976-77 3.0 Carrera
- Porsche 911 1978-1983 3.0L / SC
- Porsche 911 1984-1986 3.2L
- Porsche 911 1987-1989 3.2L G50
- Porsche 911 1978-1989 3.3L Turbo (930)
- Porsche 964 (911) C2 1989-93
- Porsche 964 (911) C4 1989-93
- Porsche 964 (911) RS 3.6L 1991-93
- Porsche 964 (911) RS 3.8L 1991-93
- Porsche 964 (911) TURBO 3.3L 1991-93
- Porsche 964 (911) TURBO 3.6L 1991-93
- Porsche 993 (911) C2 1994-97
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) RS 1994-97
- Porsche 993 (911) C2S 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) GT2 1994-97
- Porsche 993 (911) TURBO S 1994-97
- Porsche 996 TURBO 2000-05
- Porsche 996 GT2 2001-05
- Porsche 996 GT3 MKI 1999-02
- Porsche 996 GT3 MKII 2003>>
- Porsche 996 GT3 RS 2003-04
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MK1 GT3 / GT3 RS 2007-09
- Porsche 997 MK1 GT2 2007-09
- Porsche 997 MKII GT3 / GT3 RS 2010-11
- Porsche 997 MKII Turbo 2010-13
- Porsche 997 MKII GT2 RS 2011-13
Information
Lock nut for transmission pinion shaft - M30 x 1.5
The Genuine Porsche 99903403300 transmission pinion shaft lock nut is an OE M30 x 1.5 shouldered lock nut for selected Porsche manual gearbox applications, including 911 1972–1989, 964, 993, 996 Turbo, 997 Turbo and GT3 models. It secures key transmission shaft components and is ideal for gearbox rebuilds, transmission repairs or restoration using Genuine Porsche hardware.
Sold individually
Fits:
Porsche 911 - 1972 to 1989 (915 and G50)
Porsche 964 - 1989 to 1994
Porsche 993 - 1994 to 1994
Porsche 996 turbo - 2001 to 2005
Porsche 997 turbo - 2007 to 2013
Porsche 996 GT3 - 2003 to 2005
Porsche 997 GT3 - 2007 to 2011
Manual transmission
Diagram ref no 20
This nut is used in selected Porsche manual gearbox assemblies, including 915, G50 and later Turbo / GT gearbox applications where specified.
What This Part Does / Functions
• Secures transmission shaft components in position
• Helps maintain correct gearbox shaft assembly preload and alignment
• Supports proper operation of the pinion shaft / main shaft assembly
• Helps prevent loosening under drivetrain load and vibration
• Provides correct OE Porsche M30 x 1.5 thread and shouldered nut design
• Replaces a worn, damaged, previously removed or incorrectly reused lock nut
• Supports correct transmission rebuild and gearbox service procedures
• Maintains factory Porsche gearbox hardware specification.
Why Replace This Part?
Transmission lock nuts are critical gearbox fasteners. During gearbox rebuilds or shaft service, the original nut may be removed, disturbed, damaged or no longer suitable for reuse. A worn, distorted or incorrectly secured shaft nut can affect gearbox assembly, shaft retention and long-term reliability. Replacing it with a Genuine Porsche OE transmission shaft lock nut helps ensure the gearbox is rebuilt using the correct factory-specified hardware.
When to Replace This Part
• During manual gearbox rebuild or overhaul
• When servicing the transmission main shaft or pinion shaft
• If the original nut is worn, damaged, distorted or corroded
• If the nut has been removed during gearbox disassembly
• During differential, gear set or shaft bearing replacement
• If the original lock nut no longer secures correctly
• When restoring a Porsche gearbox with correct OE hardware
• Whenever Porsche workshop procedure recommends replacement after removal.
Where It Fits on the Car
This lock nut fits inside the manual transmission / gearbox assembly. It is used on the transmission main shaft or pinion shaft, depending on the gearbox type and application.
Installation requires correct Porsche gearbox tools, torque procedure and workshop specifications. This is a specialist transmission component and should be fitted by an experienced Porsche gearbox technician.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99903403300
The product you are viewing cross references to these numbers
The Genuine Porsche 99903403300 transmission pinion shaft lock nut is an OE M30 x 1.5 shouldered lock nut for selected Porsche manual gearbox applications, including 911 1972–1989, 964, 993, 996 Turbo, 997 Turbo and GT3 models. It secures key transmission shaft components and is ideal for gearbox rebuilds, transmission repairs or restoration using Genuine Porsche hardware.
Sold individually
Fits:
Porsche 911 - 1972 to 1989 (915 and G50)
Porsche 964 - 1989 to 1994
Porsche 993 - 1994 to 1994
Porsche 996 turbo - 2001 to 2005
Porsche 997 turbo - 2007 to 2013
Porsche 996 GT3 - 2003 to 2005
Porsche 997 GT3 - 2007 to 2011
Manual transmission
Diagram ref no 20
This nut is used in selected Porsche manual gearbox assemblies, including 915, G50 and later Turbo / GT gearbox applications where specified.
What This Part Does / Functions
• Secures transmission shaft components in position
• Helps maintain correct gearbox shaft assembly preload and alignment
• Supports proper operation of the pinion shaft / main shaft assembly
• Helps prevent loosening under drivetrain load and vibration
• Provides correct OE Porsche M30 x 1.5 thread and shouldered nut design
• Replaces a worn, damaged, previously removed or incorrectly reused lock nut
• Supports correct transmission rebuild and gearbox service procedures
• Maintains factory Porsche gearbox hardware specification.
Why Replace This Part?
Transmission lock nuts are critical gearbox fasteners. During gearbox rebuilds or shaft service, the original nut may be removed, disturbed, damaged or no longer suitable for reuse. A worn, distorted or incorrectly secured shaft nut can affect gearbox assembly, shaft retention and long-term reliability. Replacing it with a Genuine Porsche OE transmission shaft lock nut helps ensure the gearbox is rebuilt using the correct factory-specified hardware.
When to Replace This Part
• During manual gearbox rebuild or overhaul
• When servicing the transmission main shaft or pinion shaft
• If the original nut is worn, damaged, distorted or corroded
• If the nut has been removed during gearbox disassembly
• During differential, gear set or shaft bearing replacement
• If the original lock nut no longer secures correctly
• When restoring a Porsche gearbox with correct OE hardware
• Whenever Porsche workshop procedure recommends replacement after removal.
Where It Fits on the Car
This lock nut fits inside the manual transmission / gearbox assembly. It is used on the transmission main shaft or pinion shaft, depending on the gearbox type and application.
Installation requires correct Porsche gearbox tools, torque procedure and workshop specifications. This is a specialist transmission component and should be fitted by an experienced Porsche gearbox technician.
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99903403300
99903403300
91530228100
The product you are viewing cross references to these numbers
Price: £19.73
In stock
Related products
Vehicle Group
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) TURBO S 1994-97
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII Turbo 2010-13
- Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
Information
Shaft sealing ring. 40 x 60 x 9. Price is for each.
Fits:
Porsche 993 C4 1995-98
Porsche 993 Turbo 1996-98
Porsche 996 C4 1999-05
Porsche 996 Turbo 2001-05
Porsche 997.1 C4 2006-08
Porsche 997.1 Turbo 2007-10
Porsche 997.2 C4 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 C4 2012-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 3
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911345441
The product you are viewing cross references to these numbers
Fits:
Porsche 993 C4 1995-98
Porsche 993 Turbo 1996-98
Porsche 996 C4 1999-05
Porsche 996 Turbo 2001-05
Porsche 997.1 C4 2006-08
Porsche 997.1 Turbo 2007-10
Porsche 997.2 C4 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 C4 2012-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 3
Related reference numbers
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99911345441
PCG34901002
99911345440
99911345441
843.680
The product you are viewing cross references to these numbers
Price: £38.71
In stock
Vehicle Group
- Porsche Boxster 987 MKII 2.9L 2009-12
- Porsche Boxster S 987 MKII 3.4L 2009-12
- Porsche Boxster 981 2.7L 2012-16
- Porsche Boxster 981 S / GTS 3.4L 2012-16
- Porsche Boxster 718 2.0L Manual (300 Bhp) 2017>>
- Porsche Boxster 718 2.0L PDK (300 Bhp) 2017>>
- Porsche Boxster S 718 2.5L Manual (350 Bhp) 05/2017>>
- Porsche Boxster S 718 2.5L PDK (350 Bhp) 05/2017>>
- Porsche Boxster T 718 2.0L Manual (300 Bhp) 01/2019>>
- Porsche Boxster T 718 2.0L PDK (300 Bhp) 01/2019>>
- Porsche Boxster GTS 718 2.5L Manual (365 Bhp) 05/2017>>
- Porsche Boxster GTS 718 2.5L PDK (365 Bhp) 05/2017>>
- Porsche 997 MKII Carrera C2 3.6L 2009-12
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C2S 3.8L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII GT3 / GT3 RS 2010-11
- Porsche 997 MKII Turbo 2010-13
- Porsche 997 MKII GT2 RS 2011-13
- Porsche 991.1 Carrera C2 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C2S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.1 Turbo 3.8L (520 Bhp) 2014-16
- Porsche 991.1 Turbo S 3.8L (560 Bhp) 2014-16
- Porsche 991.1 R 4.0L (500 Bhp) 2016
- Porsche 991.1 GT3 3.8L (475 Bhp) 2014-16
- Porsche 991.1 GT3 RS 4.0L (500 Bhp) 2015-16
- Porsche 991.2 Carrera 2 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Carrera 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Carrera 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Carrera 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 2 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Cabriolet 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Cabriolet 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Targa 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Targa 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Turbo Coupe 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Coupe 3.8L (580 Bhp) 2016-19
- Porsche 991.2 Turbo Cabriolet 3.8L (540 Bhp) 2016-19
- Porsche 991.2 Turbo S Cabriolet 3.8L (580 Bhp) 2016-19
- Porsche 991.2 GT3 4.0L (500 Bhp) / GT3 RS 4.0L (520 Bhp) 2017-19
- Porsche 991.2 GT2 RS 3.8L PDK (700 bhp) 2018-19
- Porsche Cayman 2.9L 987C MKII 2009-12
- Porsche Cayman S / R 3.4L 987C MKII 2009-12
- Porsche Cayman 2.7L 981 2013-16
- Porsche Cayman S / GTS 3.4L 981 2013-16
- Porsche Cayman 718 2.0L Manual (300 Bhp)
- Porsche Cayman 718 2.0L PDK (300 Bhp)
- Porsche Cayman S 718 2.5L Manual (350 Bhp)
- Porsche Cayman S 718 2.5L PDK (350 Bhp)
- Porsche Cayman T 718 2.0L Manual (300 Bhp)
- Porsche Cayman T 718 2.0L PDK (300 Bhp)
- Porsche Cayman GTS 718 2.5L Manual (365 Bhp)
- Porsche Cayman GTS 718 2.5L PDK (365 Bhp)
Information
Shaft sealing ring for clutch. 40 x 57 x 6. For cars with PDK transmission.
Fits:
Porsche 997.2 2009-12
Porsche 991.1 2012-16
Porsche 991.2 2017-18
Porsche 987.2 Boxster 2009-12
Porsche 981 Boxster 2013-16
Porsche 982 (718) Boxster) 2017>>
Porsche 987C.2 Cayman 2009-13
Porsche 981C Cayman 2014-16
Porsche 982C (718C) Cayman 2017>>
Click 'Zoom in' for large parts diagram.
Diagram ref no 18
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
9A714242600
The product you are viewing cross references to these numbers
Fits:
Porsche 997.2 2009-12
Porsche 991.1 2012-16
Porsche 991.2 2017-18
Porsche 987.2 Boxster 2009-12
Porsche 981 Boxster 2013-16
Porsche 982 (718) Boxster) 2017>>
Porsche 987C.2 Cayman 2009-13
Porsche 981C Cayman 2014-16
Porsche 982C (718C) Cayman 2017>>
Click 'Zoom in' for large parts diagram.
Diagram ref no 18
Related reference numbers
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9A714242600
9A714242600
9G111680700
The product you are viewing cross references to these numbers
Price: £18.82
Orderable
Vehicle Group
- Porsche 993 (911) C4 1994-97
- Porsche 993 (911) C4S 1994-97
- Porsche 993 (911) TURBO 1994-96
- Porsche 993 (911) TURBO S 1994-97
- Porsche 996 C4 3.4L 1997-08/01
- Porsche 996 C4 3.6L 09/01-2005
- Porsche 996 TURBO 2000-05
- Porsche 997 MK1 Carrera 4 3.6L 2005-08
- Porsche 997 MK1 Carrera 4S 3.8L 2005-08
- Porsche 997 MK1 TURBO 2007-09
- Porsche 997 MKII Carrera C4 3.6L 2009-12
- Porsche 997 MKII Carrera C4S 3.8L 2009-12
- Porsche 997 MKII Turbo 2010-13
- Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
Information
Shaft sealing ring. 40 x 60 x 9. Price is for each.
Fits:
Porsche 993 C4 1995-98
Porsche 993 Turbo 1996-98
Porsche 996 C4 1999-05
Porsche 996 Turbo 2001-05
Porsche 997.1 C4 2006-08
Porsche 997.1 Turbo 2007-10
Porsche 997.2 C4 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 C4 2012-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 3
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911345441
The product you are viewing cross references to these numbers
Fits:
Porsche 993 C4 1995-98
Porsche 993 Turbo 1996-98
Porsche 996 C4 1999-05
Porsche 996 Turbo 2001-05
Porsche 997.1 C4 2006-08
Porsche 997.1 Turbo 2007-10
Porsche 997.2 C4 2009-12
Porsche 997.2 Turbo 2010-13
Porsche 991.1 C4 2012-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 3
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911345441
PCG34901002
99911345440
99911345441
843.680
The product you are viewing cross references to these numbers
Price: £14.50
In stock
Vehicle Group
- Porsche 991.1 Carrera C2 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C2S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.1 Carrera C4 3.4L (350 Bhp) 2012-16
- Porsche 991.1 Carrera C4S / GTS 3.8L (400/430 Bhp) 2012-16
- Porsche 991.2 Carrera 2 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Carrera 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Carrera 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Carrera 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 2 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Cabriolet 2S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Cabriolet 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Cabriolet 4S / GTS 3.0L (420/450 Bhp) 2016-19
- Porsche 991.2 Targa 4 3.0L (370 Bhp) 2016-19
- Porsche 991.2 Targa 4S / GTS 3.0L (420/450 Bhp) 2016-19
Information
Manual transmission output shaft seal. 40 x 55 x 7 Sold each.
Fits:
Porsche 991.1 Carrera 2011-16 7-speed manual transmission
Porsche 991.2 Carrera 2016-19 7-speed manual transmission
Porsche 991 6-Speed GT Sports manual transmission 2015-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 36
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99133280500
The product you are viewing cross references to these numbers
Fits:
Porsche 991.1 Carrera 2011-16 7-speed manual transmission
Porsche 991.2 Carrera 2016-19 7-speed manual transmission
Porsche 991 6-Speed GT Sports manual transmission 2015-16
Click 'Zoom in' for large parts diagram.
Diagram ref no 36
Related reference numbers
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99133280500
99133280500
484.690
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Price: £22.98
Orderable