2002 Ford Explorer Sport Trac 4X4. Re: Vibration/Thumping like sound. Drivers front

Rebalance tire… No change. Took off tire, rotor, and caliper. When turning hub by hand, "play" is about 3/8 inch, before any movement at the short shaft. Someone mentioned it could be transfer case. When tire was on, and off the ground… No noticeable play or noises when rocking the tire at the 12 and 6 o'clock positions. But a little bit of clicking/chunking while rocking the tire in the 9 and 3 o'clock positions. Tire didn't spin very freely at all. Took a bit of effort. Rotor is about 6 months old. No noticeable scarring on rotor surface. Did notice the rubber stop was hitting on the top of the "A" arm. Not significantly, just the impression of the stop in the dirt/grease. Any input will be greatly appreciated!

The transfer would not be a specific to the left front but a bad U-joint in the drive axle would be.