Well I did take the X5 to an independent BMW specialty shop. They hadn't heard of a wheel bearing sliding in it's bore, though after they read the SIB everyone agreed it was possible.
The tech went for a test drive, noted how the noise was only during turns, could be felt through the floor board and then put the car on the lift. He checked the bolts for the sub-frame carrier, as he found these loose on a different X5. One sub-frame carrier bolt was 1/4 of a turn loose. He used a pry bar on several of the suspension pieces but nothing moved irregularly.
The X5 was lowered and he pulled on the top of one tire. POP.
He couldn't repeat it, but thought the wheel bearing was a definite possibility.
The X5 went home and continued to clunk. Several weeks later I dropped the splash guard and checked the torque on all the suspension bolts & nuts which were loosened during the CV boot replacement.
Both nuts (L & R side) for the Control Arm (Item #4) connection to the sub-frame carrier were significantly undertorqued at about 75 Nm. Spec is 100 Nm PLUS a 90 degree turn. I guess here is one case "good and tight" is not sufficient. Lesson here is to actually follow the torque in TIS!!
So the award goes to Big "J" for having the best solution.
