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Original Porsche Part Genuine Porsche part 90130291811
• This part is brand new and unused.
• Please verify that it is 100% suitable for your specific vehicle before purchase to ensure compatibility.
Before purchasing thoroughly check part to confirm compatibility.
- We are unable to provide fitting details for this product at this time. Please contact us for further information.

Fits:
Porsche 911 - 1969 to 1986
For 915 gearbox
Uprating or modifying your 915 gearbox? Choose from the gear ratios shown below
- High grade fine-grained 9310 VAR alloy steel material
- CNC-machined
- Formula One tooth profile
- Shot-peened
- REM-polished
Diagram ref no 5
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
91530290582
The product you are viewing cross references to these numbers
- 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
Fits:
Porsche 911 - 1965 to 1971
For 901 gearbox
Available with different gear ratios - example - 25:26 (number of teeth on each gear) - 1.04:1 (gear ratio)
25:26 - 1.04:1
24:27 - 1.13:1 (Porsche code "Q")
23:27 - 1.17:1 (Porsche code "P")
23:28 - 1.22:1 (Porsche code "O")
23:29 - 1.26:1 (Porsche code "N")
22:29 - 1.32:1 (Porsche code "M")
22:30 - 1.36:1 (Porsche code "L")
21:29 - 1.38:1 (Porsche code "LA")
21:30 - 1.43:1 (Porsche code "K")
21:31 - 1.48:1 (Porsche code "J")
20:31 - 1.55:1 (Porsche code "I")
20:32 - 1.60:1 (Porsche code "HA")
19:31 - 1.63:1 (Porsche code "T")
19:32 - 1.68:1 (Porsche code "H")
Diagram ref no 3
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90130290910
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
This gear set fits inside the 901 gearbox on Porsche 911 models. It is installed within the internal transmission gear train for the 4th and 5th gear positions according to the factory gearbox layout.
Fits:
Porsche 911 - 1965 to 1971
For 901 gearbox
Available with different gear ratios - example - 31:22 (number of teeth on each gear) - 0.71:1 (gear ratio)
31:22 - 0.71:1 (Porsche code "ZD")
29:22 - 0.76:1 (Porsche code "ZA")
29:23 - 0.79:1 (Porsche code "Z")
28:23 - 0.82:1 (Porsche code "Y")
28:24 - 0.86:1 (Porsche code "X")
27:24 - 0.89:1 (Porsche code "W")
27:25 - 0.93:1 (Porsche code "V")
26:25 - 0.96:1 (Porsche code "U")
26:26 - 1.00:1 (Porsche code "T")
25:26 - 1.04:1 (Porsche code "S")
25:27 - 1.08:1 (Porsche code "R")
24:27 - 1.13:1 (Porsche code "Q")
23:27 - 1.17:1 (Porsche code "P")
23:28 - 1.22:1 (Porsche code "O")
23:29 - 1.26:1 (Porsche code "N")
22:29 - 1.32:1 (Porsche code "M")
22:30 - 1.36:1
Diagram ref no 4 and 5
The 4th and 5th gear set forms part of the internal gear train inside the 901 gearbox. These gears transfer engine power through the transmission at higher road speeds, supporting smooth cruising, correct gear ratios, and reliable power delivery.
Functions
• Replaces the 4th and 5th gears in the 901 gearbox
• Supports correct transmission gear ratio operation
• Helps restore smooth higher-gear driving performance
• Transfers engine power through the gearbox
• Replaces worn, noisy, chipped, or damaged original gears
• Suitable for gearbox rebuilds and transmission restoration
• OE Match replacement for classic Porsche 901 gearbox repair.
Why Replace This Part?
Gearbox gears can wear, chip, pit, become noisy, or suffer tooth damage due to age, high mileage, poor lubrication, previous gearbox wear, or hard use. Worn 4th or 5th gears may cause whining, vibration, poor engagement, metal debris in the oil, or reduced transmission reliability. Replacing the gear set during gearbox overhaul helps restore correct operation and protects related transmission components.
When to Replace This Part
• 4th or 5th gear is noisy, worn, chipped, or damaged
• Gearbox whine or vibration is present in higher gears
• Metal particles or gear debris are found in the gearbox oil
• The gearbox is being rebuilt or inspected
• Gear ratios are being restored to original specification
• Related synchro parts, bearings, or shafts are being replaced
• The vehicle is undergoing Porsche 911 transmission restoration
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90130291310
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)
Fits:
Porsche 911 - 1965 to 1971
Porsche 914 - 1970 to 1976
Please note:
This part is on special order terms and is made to order that could take 6-8+ weeks.
It is not a subject to cancellation or return if not required.
Available with different gear ratios - example - 9:31 (number of teeth on each gear) - 3.44:1 (gear ratio)
9:31 - 3.44:1
8:31 - 3.88:1
8:35 - 4.38:1
7:31 - 4.43:1
6:32 - 5.33:1
Diagram ref no 9
Related reference numbers
Related, superseded, cross reference or alternative numbers for comparison.
90130290102
The product you are viewing cross references to these numbers
- Porsche 911 1965-1968 2.0L / 912 SWB (F)
- Porsche 911 1968-1973 2.2L / 2.4L / 2.7L RS LWB (F)