I've been searching high and low and have not found a DIY for spedometer drive gear replacement. I can't even find the procedural detail in the Bentley manual:
- Volkswagen > A4 > 1999-20064 speed automatic transmission 01M, 39 - Differential, Removing and Installing
- 2 - Speedometer drive With marking for oil level indication [Speedometer drive ]
- Speedometer drive - With transmission installed, check gear oil in final drive Final Drive Oil, Checking .
My symptom: spedometer starts twitching at approx 65-70mph and cruise control hunts. Tachometer and other gauges are stable and don't bounce while this is happening.
I've been told that the spedometer drive gear on the Mk4 01M automatic is known for this.
I was able to find the VW part: Mfg#: 01M409187 and am hoping to replace it, drain the final drive oil in the hope of removing the plastic debris and changing the differential gear oil for maintenance.
Any suggestions/tips are greatly appreciated.