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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: €24.08
Arriving soon
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
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: €49.15
In stock
Vehicle Group
- 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
Manual transmission main shaft seal. 26.5 x 40 mm.
Its function is to act as a primary seal to retain oil around the input (main) shaft of a manual transmission, preventing fluid leaks and protecting driveline components.
Fits:
Porsche 911 Carrera / Turbo 1987 - 1989
Porsche 964 Carrera / Turbo 1989 - 1994
Porsche 993 Carrera / Turbo 1995 - 1998
Porsche 996 Turbo / GT2 / GT3 2001 - 2005
Porsche 997.1 Turbo / GT2 2007 - 2009
Porsche 997.2 Turbo / GT2 2010 - 2013
Porsche 996 GT3 1999 - 2005
Porsche 997 GT3 2007 - 2011
Diagram ref no 12
Application:
• Manual transmission input shaft oil seal
• Cross-referenced with superseded part number: 99911332640
The input shaft seal sits around the input/main shaft where it enters the transmission case. Its job is to keep transmission fluid from leaking out and to prevent contamination from entering the gearbox. By maintaining a secure seal around the rotating shaft, this component helps preserve optimal lubrication, reduce wear, and support smooth gear operation.
In a manual transmission, the input shaft takes power from the clutch and delivers it into the gearbox. The seal must endure rotation, pressure changes, heat, and exposure to transmission fluid, forming a durable barrier that keeps oil inside while preventing dirt and debris from entering. A properly functioning input shaft seal is crucial for transmission longevity and performance.
Over time and mileage, seals can harden, crack, or lose elasticity due to heat, oil exposure, and mechanical wear. A failed input shaft seal can lead to:
• Transmission fluid leaks
• Low fluid levels
• Increased gearbox noise
• Premature wear on gears and bearings
• Potential drivetrain damage
Replacing worn or leaking seals restores proper fluid containment and protects the integrity of the transmission system, preserving performance and reducing the risk of costly repairs.
Replace the input shaft seal if you notice:
• Visible transmission fluid leaks at the bellhousing area
• Low transmission fluid levels
• Gearbox whine or unusual noises
• Transmission slipping or crunching in gear shifts
• After transmission removal or overhaul
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911332641
The product you are viewing cross references to these numbers
Its function is to act as a primary seal to retain oil around the input (main) shaft of a manual transmission, preventing fluid leaks and protecting driveline components.
Fits:
Porsche 911 Carrera / Turbo 1987 - 1989
Porsche 964 Carrera / Turbo 1989 - 1994
Porsche 993 Carrera / Turbo 1995 - 1998
Porsche 996 Turbo / GT2 / GT3 2001 - 2005
Porsche 997.1 Turbo / GT2 2007 - 2009
Porsche 997.2 Turbo / GT2 2010 - 2013
Porsche 996 GT3 1999 - 2005
Porsche 997 GT3 2007 - 2011
Diagram ref no 12
Application:
• Manual transmission input shaft oil seal
• Cross-referenced with superseded part number: 99911332640
The input shaft seal sits around the input/main shaft where it enters the transmission case. Its job is to keep transmission fluid from leaking out and to prevent contamination from entering the gearbox. By maintaining a secure seal around the rotating shaft, this component helps preserve optimal lubrication, reduce wear, and support smooth gear operation.
In a manual transmission, the input shaft takes power from the clutch and delivers it into the gearbox. The seal must endure rotation, pressure changes, heat, and exposure to transmission fluid, forming a durable barrier that keeps oil inside while preventing dirt and debris from entering. A properly functioning input shaft seal is crucial for transmission longevity and performance.
Over time and mileage, seals can harden, crack, or lose elasticity due to heat, oil exposure, and mechanical wear. A failed input shaft seal can lead to:
• Transmission fluid leaks
• Low fluid levels
• Increased gearbox noise
• Premature wear on gears and bearings
• Potential drivetrain damage
Replacing worn or leaking seals restores proper fluid containment and protects the integrity of the transmission system, preserving performance and reducing the risk of costly repairs.
Replace the input shaft seal if you notice:
• Visible transmission fluid leaks at the bellhousing area
• Low transmission fluid levels
• Gearbox whine or unusual noises
• Transmission slipping or crunching in gear shifts
• After transmission removal or overhaul
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911332641
99911332641
99911332640
The product you are viewing cross references to these numbers
Price: €9.30
In stock
Vehicle Group
- 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
Manual transmission main shaft seal. 26.5 x 40 mm
Fits:
Porsche 911 Carrera / Turbo 1987-89
Porsche 964 Carrera / Turbo 1989-94
Porsche 993 Carrera / Turbo 1995-98
Porsche 996 Turbo / GT2 / GT3 2001-05
Porsche 997.1 Turbo / GT2 2007-09
Porsche 997.2 Turbo / GT2 2010-13
Porsche 996 GT3 1999-05
Porsche 997 GT3 2007-11
Click 'Zoom in' for large parts diagram.
Diagram ref no 12
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911332641
The product you are viewing cross references to these numbers
Fits:
Porsche 911 Carrera / Turbo 1987-89
Porsche 964 Carrera / Turbo 1989-94
Porsche 993 Carrera / Turbo 1995-98
Porsche 996 Turbo / GT2 / GT3 2001-05
Porsche 997.1 Turbo / GT2 2007-09
Porsche 997.2 Turbo / GT2 2010-13
Porsche 996 GT3 1999-05
Porsche 997 GT3 2007-11
Click 'Zoom in' for large parts diagram.
Diagram ref no 12
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
99911332641
99911332641
The product you are viewing cross references to these numbers
Price: €36.74
In stock