VS rear back end vibration

[Thacks]

Hi there, could someone please help. I've got a VS Wagon S2, I've just had the diff replaced (2nd hand), and now when travelling around 90 - 110kph and try to accellerate, I get this horrible noise and vibration in the back end, this never used to happen. I have been informed by the mechanic that I will have to replace the rear shocks soon, but surely this is not the problem.
please help, thanx

[Krustyone]

Are the universal joints connected properly. I.e... Are the aligned.

[HICOMPVN]

yeah check the your prop shaft is reinstalled properly, other wise you uni's will shit themself, and that's no fun!!!!!.

easiest way to check and i know it's the most annoying part, get underneath the rear end loosen prop shaft and rotate 90 degrees, do it back up go for a drive. still vibrating after you have rotated the shaft 360 degrees, prop shaft then needs balancing!!

[Thacks]

thanx for info, I will try tonight