Go back up to the top of the page and reread jeepdaddys post. When you have someone turning the wheel have them do it slow and steady. Have them hold the wheel at about 10 oclock and slowly turn to about 2 oclock, then slowly back to 10. They need to keep doing this the entire time that you are looking for the bad part. Raise your hood, start the jeep, have someone start sawing back an forth on the wheel slowly, start at the steering shaft, look closely at the u joints, The one you pictured is usually a culprit. Then move under the jeep, look at the two plates that the steering box is mounted to, the mounting bolts and the box. Then move on to the drag link and tie rod. Its kinda hard to explain exactly what your looking for here but I'll try. If the nuts that screw on to the tie rod ends(tre) are loose then the tapered part of the tre will move some. If the nut is tight but the tre is bad there will be movement in the ball and socket part of the tre.
Then move on to the ball joints. Get a jack and place it on one side, look at the ball joints on that same side, start working the jack until the tire is off the ground. Usually if a ball joint is bad there will be some movement in it just as the tire leaves the ground. If you didnt see any movement have someone continue to look at the ball joints while you check the wheel bearings. You might need to raise the wheel a little more to do this. Grab the tire at 12 oclock and 6 oclock, try to move it up and down