their might be something in the archives that will take care of you on this. EDIT my sugggestion would be to R&R the ujoints & I'd be surprised if that didn't take care of you. Be sure after you get em in to set the shaft down on the ground & whack each ear right behind the ujoint cap several good licks with a BFH flip it 180 & do the other side. When you are done you want to be able to by hand move each ujoint thru its range of travel in both planes & have it move FREELY, try it before & after you whack it & you'll feel the difference & know when you have it right. and you might have a driveline shop check the balance while you are at it, call them & see if the ujoints need to be in or out.