Transaxle – General Information, Codes, and Gear Ratios

Overview

This guide helps you identify and understand the transaxle in your Porsche 944 S / S2 with the 16v engine. Knowing your transaxle type is key for maintenance, repairs, or upgrades. You’ll learn how to find the transaxle code and use it to check specific details like gear ratios and features unique to the S / S2 variant.

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Tools Required

• Inspection mirror
• Flashlight
• Rag (for cleaning debris)

Step-by-Step Procedure

Step 1: Locate the Transaxle Code

1. Park your Porsche 944 S / S2 on a level surface and ensure it’s safe to work under the car (e.g., on jack stands or a lift).
2. Locate the top flange near the front of the transaxle. This is where the code is stamped, but it’s tricky to see without the right tools.
3. Use an inspection mirror and a flashlight to view the code. Position the mirror to reflect the stamped area into your line of sight.
4. If the code is hard to read due to dirt or grime, wipe the area with a rag until it’s clear.

Step 2: Identify Your Transaxle Type

5. Match the code you found to one of the transaxle types listed below, specific to the Porsche 944 S / S2 (1989-1991) with the 16v engine:
6. Code AOS (Type 083F): No limited-slip differential (LSD).
   • 1st Gear: 10:35 (3.500)
   • 2nd Gear: 17:35 (2.059)
   • 3rd Gear: 25:35 (1.400)
   • 4th Gear: 29:30 (1.034)
   • 5th Gear: 36:28 (0.778)
   • Reverse: 12:42 (3.500)
   • Final Drive Ratio (FDR): 8:31 (3.875)
7. Code AOT (Type 083F): With limited-slip differential (LSD).
   • 1st Gear: 10:35 (3.500)
   • 2nd Gear: 17:35 (2.059)
   • 3rd Gear: 25:35 (1.400)
   • 4th Gear: 29:30 (1.034)
   • 5th Gear: 36:28 (0.778)
   • Reverse: 12:42 (3.500)
   • Final Drive Ratio (FDR): 8:31 (3.875)
8. Code ASV (Type 083F): Switzerland model, no LSD, with transmission enclosing and additional oil cooler.
   • 1st Gear: 10:35 (3.500)
   • 2nd Gear: 17:35 (2.059)
   • 3rd Gear: 25:35 (1.400)
   • 4th Gear: 29:30 (1.034)
   • 5th Gear: 36:28 (0.778)
   • Reverse: 12:42 (3.500)
   • Final Drive Ratio (FDR): 8:31 (3.875)
9. Code ASW (Type 083F): Switzerland model, with LSD, transmission enclosing, and additional oil cooler.
   • 1st Gear: 10:35 (3.500)
   • 2nd Gear: 17:35 (2.059)
   • 3rd Gear: 25:35 (1.400)
   • 4th Gear: 29:30 (1.034)
   • 5th Gear: 36:28 (0.778)
   • Reverse: 12:42 (3.500)
   • Final Drive Ratio (FDR): 8:31 (3.875)

Step 3: Verify and Record Your Findings

10. Double-check the code against the transaxle to ensure you read it correctly.
11. Write down the code and its corresponding details (gear ratios, LSD status, etc.) for future reference.

Post Procedure Checklist

• Confirm the transaxle code is legible and matches one of the S / S2-specific types (AOS, AOT, ASV, or ASW).
• Ensure all tools are removed from under the car.
• Check that the work area is clean and free of debris.

Sources

• Clark’s Garage
• Pelican Parts
• Porsche 944 Workshop Manual, Volume 1
• Youtube