I have a 2014 Ford Transit 6 speed manual 2.2 TDi m/h (Chausson body) which came off the Ford production line in 2012.
I have done approx 50k KM and have owned it from new.
While driving locally (fortunately) the engine started to increase revs in 5th gear and then settle again. Well, nothing to worry about hopefully, just a minor glitch! Another few miles and the engine increased revs and lost drive completely in 5th gear. Not the end of the world as all other gears were working.
A trawl through Google Ford Transit discussion boards and seems endless numbers of people have had the same problem.

Long story short, gearbox out and taken to specialist repair workshop where the chap grinned and said 'hmmm....another one!'
It appears (as he gave me the layshaft as a souvenir) that the 5th gear cog is welded on to the layshaft whereas all of the other gears are machined from their own original shaft. Stupidly, I said to him that naturally the problem gear has been modified so last time I have to do this???? It appears that the gear has not been modified but strangely he said that he rarely has to do them again.
One of the reasons I bought a Ford chassis m/h is that I thought all of the bugs would have been ironed out by now (not including the new generation Ford chassis). Seems every 6 speed gearbox has the potential to fail for exactly the same reason. Bearing in mind that my m/h gets less of a beating than the average Transit trade van, it was disappointing......to put it politely!
His last comment to me as I picked up the gearbox was 'try and drive it so that you are not putting heavy load on 5th gear'.
Fortunately I was already in the car when I made my last comment!
Total bill......£1500.............