I think I am experiencing the same issue on my 2.0 JTDM, would be keen to know if any of you have fixed this issue and how much it costs as it is a bit annoying - rectified with turning up the stereo but when I have people in the car it is quite apparent and annoying!
Seems that it could be, driveshaft or gearbox bearings?
This is what I have posted in another thread with my experiences of it...
Hello, I was about to post about this noise, as I believe I am experiencing the same noise/rubbing sound that you have described, that is an engine related noise and not caused by the movement of parts etc outside of the engine.
It is annoying to say the least, my 2.0 JTDM 159 has done 93K now, and I have demonstrated it to a mechanic that I use of which he does not know what is causing it either, other than its something to do with the engine itself and only happens once the car is moving.
It is like a gurgling vibration sound, something you would expect from a wheel bearing or something as it rotates and it resonates through the car in particular more noticeable during town driving. I really would like to fix this problem as it is annoying to say the least. It cannot be heard when the car is idling, or revved whilst in neutral.
Did you ever get any closer to finding a solution to yours?