Lumpy grinding noise. Can anyone help?

[transitgav]

Hi all,

I have a 2005 2.0 fwd with 39k on it. It has recently started to make a grinding noise. When moving away and the window is open it is a loud noise which is more like a thud thud thud which gets closer together the quicker you go. At speed it is a dull whine. It drives perfectly pulling through the gears with no problem. Selection on first sometimes slightly awkward but has been like that for the three years I have had it. I took it to my usual garage who said it was the gearbox so took it to a specialist gearbox place who said it wasn't. They then stripped it down to find the problem. It makes the noise even on the ramps I am told. They checked the diff which is fine and changed the drive shafts all to no avail. They are now saying it could be the main shaft in the gearbox?

Does anyone have experience of a similar problem or have any ideas as I think the garage are guessing now as they say they never saw a transit with this problem before.

Thanks in advance

[loot]

If it is doing it while running and in neutral then that discounts anything drive related so main bearing in the box sounds reasonable