My U-joints blew out (rear prop shaft was literally 'loose') 2 weeks ago because of the vibration on the lift and what surprised me was that the vibes were not really pronounced while I was driving. More so on the acceleration in 1/2 gears.
Will vary from one Delica to another. My previous Delica with 2" lift, all that was needed was a 5/8" t-case drop to align the pinion with the yoke.
On my current Delica, even dropping the T-case 1", the pinion/yoke will not align well enough so I need to go to a suspension shop to have them put in the correct shim.
These rear driveshafts are so darn short, they're almost impossible to balance properly (had mine done at a pro-balancing shop).
Just make sure when you do the lift that you cancel out any neg/pos angles in between the rear diff pinion and t-case yoke. Also a rear prop shaft balance wouldn't hurt.
As it sits now, I'll probably go through my new ujoints in 2-3 months unless I get that angle correct.
Aside from that, it's a piece of cake (blackforest)
