here's the deal. i have a 2000 xj with a 3.5 RE lift. i installed an IRO hack 'n' tap. i have shims to install just waiting for extended centering pins so i can put them in. when i let off of the accelerator at 40 mph or above i get a clunk of some sort and rapid deceleration. when i reengage the accelerator i get another clunk. vibrations are prevalent in the rear at speeds of 40 mph and above. will shims fix this? or is there more for me to worry about. all u-joints are sound and sturdy this far. i have taken the driveshaft in the out numerous times, cleaned the yokes of rust deposits (so the u-joints seat properly), and even checked the yoke on the output shaft of the transfer case. my trans mount seems sound enough. any help would be greatly appreciated. i have reached the point of frustration . thanks guys.

-brandon

 

bump

 

check all mounts including engine mounts hard to tell it could be many things