earlyrover, de rien monsieur. I'm actually English and old(ish) but I can't seem to stop playing with cars ever since I retired 4 years ago and even before then (must be totally mad). A bit different from my earlier days in an office based career in Construction Management. What else would one be doing 'playing golf, going on holiday, sand yachting, bike rideouts' etc, totally mad, LOL

My shaft balance was $50.

Just get it balanced.

This is an excellent write up from an Australian site for anyone rebuilding their propshafts.

www.discovery2.co.uk / Workshop :- front and Rear propshaft

I'm currently rebuilding the front and rear propshafts and following this write up certainly helps a lot. This guy in Aus has got it cracked.

Actually a UK website and I think he used to contribute to this forum.

Yeah, it's one of the ones I linked to in my sticky.

Back to your question, what year is your Disco, do you have CDL, have you tried engaging the CDL and removing the front shaft to see if the vibration is still there.
You mentioned having new u-joints, was the centering ball replaced.

Disco Mike, I have a 2003 SE7 w/out cld so it was not an option. I'm pretty much frustrate with it by now. I changed the front shaft about 4 months ago (brand new from ab) and changed u joint and rotoflex from the rear one and lubed the hole thing 2 times hopping it would do the trick.
I'm dealing now with a crank position sensor and a noisy starter so the vibration need to wait.

Having just finished my own I can sympathise and concur with your feelings it's a real PITA. ;)

Now to finally refit the driveshaft to the truck and pray it's not imbalanced. :confused::)

Well, after "rebuilding" my original front propshaft, with the double cardon U joint, for my 2004 Discovery, installing it, and feeling the subtle slight vibration that I didn't have before I "rebuilt" it, obviously caused by an out of balance condition, I tried again to rebuild it "smarter." Whomever, on this site, suggested that we use universal joints with the grease fittings coming out of the ends of one X, rather than the ones with grease fittings within the X, may be giving faulty suggestions, because this time I installed the "old fashioned" universal joints with fittings within the X, thinking that the ones with fittings on outer rim of one X may cause an imbalanced condition. The grease fitting on the sliding tube part of shaft may not be good either, so after greasing the heck out of it, I took grease fitting out of the sliding tube, and installed a threaded plug, same as I found it originally. Bingo, it is again "balanced, " and I no longer feel or sense any more of that subtle vibration when driving on super smooth pavement. Now I know for certain, that with this front double cardon prop shaft, any slight little possibly off balance weight, even from grease fittings on outer flanges of X on universal joint, very well may cause the slight painful vibration. My Rover was trying to tell me that the small additional weight on outer perimeter of U. joint, may cause imbalanced condition, but I was too stubborn to listen. Next time, when my Rover speaks to me, I will listen; it is making me a smarter laborer.