I am getting a fluttering vibration when on the freeway and feathering the throttle on and off. I have summed it up that it is behind the Tcase(replaced that last week) I need help pinning it down. Here is the set up. 4" Ord shackle flip, 14b rear Axle, drivelines unlimited drive shaft, 6deg axle shims and Tcase drop(as far as it will go without the engine hitting the firewall). the drive line is 3" out on the yolk from the Tcase. My pinion and tcase angles match. I did notice that the rear diff is ring and pinion is not perfectly set up but are really close(checked when changing the fluid). I went by the drive line shop and he is telling me to do the oposite of what I have learned here. he says to remove my 6 deg shim and aim the pinion towards the tcase more(I installed the shims with the 10 bolt due to a wobble when accelerating from a stop. a 2 deg was not enough.) I think the drive line is to short and vibrating in the transition between load and off load. Ideas? experience? knowledge?