Rear Driveshaft vibration
We have two 1998 ZJs with 3.5" Rough Country lifts. Both have rear driveshaft vibration around 40 mph. U-joints have been replaced without helping. Transfer case angle is 8 deg, driveshaft 12 deg, pinion about 4-5 degrees. That makes a 3-4 degree difference between the front and rear U-joint. I'm told that may be too much. Any ideas on how to fix this???