DSG final drive grunting noise

[Rig]

My 2006 Jetta TDI has had (since about 40K miles) little intermittent grunting noises you can hear at idle, especially when you are under the car. The sound is coming from the final drive area between the transmission and the engine. I have had the DSG and the final drive serviced, with no dirt or particles appearing in the old fluids.

The sound is like what you get when a small sealed bearing is going bad. The noises haven't gotten much louder in the last 80K miles. The DSG has always been slow to respond; like when you are trying to climb a ramp in the shop, you can't ease up the ramp because you need to give it some accelerator to kick it in gear. Also, when it is cold (below freezing), the DSG is sluggish and puts a drag on the engine even in neutral or park.

My mechanics and I have speculated it could be a torque converter issue or maybe even the enclosed transmission pump. But without taking the engine out and digging, there is no way I can tell.

Any guesses?

 

[VeeDubTDI]

The DSG doesn't have a torque converter, but it does have a dual mass flywheel. The rubber component in the flywheel will wear over time causing a rattling and/or vibration, or eventually failing altogether and causing damage to the transmission.

Think of the DSG like an automated manual transmission (a bit oversimplified, but you'll get the idea). As you apply throttle, it will engage the clutch to begin moving the vehicle. It will provide some creep like a conventional automatic, but it is functionally more like a manual than a traditional torque converter automatic.

 

[Rig]

After warming up, the sound is more like "chirp-a-chirp-a-chirp-a . . ." and it only sounds when the car is in Park or Neutral. As soon as you shift into D or R, it goes away. In the last 80K miles it has gotten a little louder and more constant than intermittent.

It does sound like a bad DMF--but not too bad. . . yet.

How hard is this job?