Answer to "looking for cause of vibration"If the clutch and the transmission were recently replaced, and the vibration began after that repair, I would check a few things. (1) When they bolted up the clutch, they possibly didn’t get it to seat right with the flywheel. This can happen usually if they put the clutch on the transmission first and then bolted it to the flywheel the access hole after bolting up the transmission. (2) If the flywheel was removed to be resurfaced. Then it is possible that it was not reinstalled correctly. Examples of this are, not lining up the dowel hole. Or not performing the flywheel runout procedure. (3) I the transmission rear support was not reinstalled, then it is possible that geometry could be off resulting in incorrect driveline angles.