I have a 98 grand cherokee laredo dana 30 in the front, when i am turning in 4x4, it feels like there is resistance for a second, then it pops. it seems to be in part time, full time and 4low, however when i tried it in full time this morning it only kind of popped once.
i have replaced trac bar, steering damper, sway bar links and bushings, and LH tie rod.
I took my axleshaft out yesterday to do the u joints, but they seem solid. and when i put the axleshaft back in and spun it, i found there was play (I could turn the axleshaft probably a quarter turn before the front driveshaft started so spin). i think its something in the diff or steering box??

 

I had this very slight pop feeling (u cud feel it in the steering-plus a slight sound) when turning and in my case it was the universal on the wheel that was going, cud be this.i wud also check my front wheel bearing for looseness (this is very easy to do raise the vehicles front end off the ground and with the wheel still on 1 hand at 12 o'clock and 1 hand at 6 o'clock shake it slowly if u find looseness thats ur problem..

 

yah im thinking its either my steering box or my ujoints