If ur feeling it the seat then it’s in the rear. Drive shaft, pumpkin, axles or bearings or a bent housing. If u only got the torque on the pinion nut to 200 lbs after the fact then u already were asking for a problem. Kim.
The pinion nut was not tightened more when checking after rebuild/vibration. The rotating torque was at 15 inch pounds so still under spec. Odd. Not sure if crush sleeve eliminator played into that.