Sounds like the splines in the middle are badly worn. I haven't come across this before, but if I were you I wouldn't drive it too far, then again I can't tell from here how bad it is... but propshafts breaking in the middle can be disastrous.. You can imagine what each half will do... Be sure you get the right one for your model, the TD5 one is slightly longer than the TDi one and not all suppliers are aware of it. I bought a 90 TD5 with a recently fitted front propshaft and the vibes from the front was the propshaft fully extended and complaining.. I got a new one from Hardy Spicers last year (in Leek, I think, by mail); they were extremely helpful and the guy I spoke to had a table with all the info for each model and it was much cheaper than LR, (around £110) and the yokes were much bigger than the TDi version, a tough item. Then again there's always Paddocks - get new nuts & bolts for the flanges.. You need 4 bolts and 8 nuts as the gearbox end flange bolts don't come out. The bolts can be sodding awkward to get off, but Difflock do a neat tool to aid removal, a socket on a slim shank. They are 9/16ths AF, by the way. If you notice a slight vibration from the new propshaft after fitting, disconnect one end and move it around the flange and bolt it up again and re-try. I believe they are 'balanced' by trial and error at the factory (info from another forum) and that's why you should always put a removed propshaft back in the same position on the flanges as when it came off. I'll leave you to figure out which wheels to jack up so you can turn the flanges around to unbolt/bolt up cuz I can't remember. It's fun.. but not much!