Transmission noise

[albion1938]

Hi. Recently purchased 1998 190 MWB tipper Mk5. Can anybody confirm what sort of noise I'd get from a propshaft centre bearing? I've got a noise like a high speed train makes, (metal wheels on metal track), like dry metal to metal, on drive and over-run, speed related. It's a 3 piece prop. The rubber on the rearmost bearing is shot, but I can't find play in the bearings, minimal play in diff. The noise doesn't sound like a wheel or diff bearing, too light, more a scrape than a rumble. The MT 75 box grumbles when pulling hard, but my last Tranny did that also, seems normal. The vendor will fix it for me, the prop is to be changed under warranty, but I don't want to have to keep taking it back, anything else I should be looking for?
Thanks in anticipation
Bernard