tdci Mass duel flywheels, bang or knock on tick over,mine was replaced by a back street garage,but there were independant ford guys.
They would only do it if Ford products were fitted as they said they wouldnt warrantee my work in all it cost not far off a £1000 for all work and fitting.
The bigest problem was the subframe possitioning afterwards,it has to be spot on else it wont steeer right.
When you do the flywheel you would be best doing the rear crank seal aswell (£1.00) as the flywheel has to come off to do this,so 2 jobs for the price of one.

It may also be the aux pully tensioner,which rummbles and gets louder and worse, this is just a new tensioner and pully maybe £150 and doable by yourself.

steve.