Mystery clutch / gearbox noise.

My n/a diesel 110 has been making an unusual noise for a while and I can't work out what it is. It seems to be coming from the gearbox/ clutch area. It's an intermittent, ratling, although sometimes it sounds as if it might be something spinning. In which case the spinning matches the vehicle speed. Sometimes it stops when I depress the clutch, sometimes not and it dosn't seem to do it when stationary. It's recently had a new clutch including thrust bearing, and this has made no difference whatsoever. Anyone got any ideas?

britpart thrust bearing???

did you check the mainshaft for play when you had the box out??

or possibly a broken plate spring

Cheers Steve

Have you tried checking the simple things...
Correct amount of oil in gear box and transfer box?
Also, check the UJs arent shagged, they can cause a noise like that