2nd Gen Explorer 4WD followup to Sticky

[Busted Knuckes]

I just read through "gijoecam's" sticky thread on 4WD not working and found that my front driveshaft still moves when 4Whi is switched on. Here's an excerpt from the thread:

Step 3) Start the vehicle and let it idle in PARK. Engage 4high. DO NOT PUT THE VEHICLE IN GEAR!!! Crawl underneath and see if you can turn the front driveshaft.
**If you can turn the front driveshaft, the transfer case is not locking. This could be due to a mechanical issue with the transfer case itself, or an electrical gremlin with the control system. Start a new thread with the results of your checks, and we'll go from there.

Now I'm trying to narrow it down to mechanical or electrical and I can't seem to find any followups regarding this.

I hear nothing when switching into 4wd hi, but there is an audible click when switching to 4wd lo from neutral. I can also hear the transfer case shifting when going into 4wd lo, although I can still turning my driveshaft by hand in lo. The lights all work fine, no blinking and cycle through like normal. Can anyone point me in the next diagnostic direction?

Thanks,
Aaron

'98 xlt 4.0 SOHC 4-door
212,000 miles