Picked my truck up yesterday afternoon. After checking the backlash, it was found to be well within 'normal' specification......actually, more toward the tight side. The service advisor stated they would just have to wait until the service engineer got back with them after driving another 6.2.
I told them to keep me informed and let me know when he would be in town so I could bring mine back in. Driving out of the lot, I noticed an immediate difference. The clunk was still there at times, but very quiet and barely noticeable to the feel. Apparently the greasing of the yoke helped more than they thought it would. I drove it about 200 mikes last night and was pretty pleased with it overall. Much much quieter.
I still believe that Ford needs to make a build change in the entire driveline from the tranny to the rear end. They are just way too sloppy, thus causing way to much annoying noise. I'm going to call the service advisor back on Monday just to thank him for the attention they put into this and getting it done in a reasonable amount of time. I feel they need to be praised when they do a good job, seeing that a lot of dealerships are pretty crappy.
I'm not giving up on getting this fixed permanently, but at least I'm not ready to shoot it every time I drive it.