Chevy & GMC Vans

Hi Everyone,
Just found this site and learned more about how the AWD works in the last 1 1/2 hours on these forums than I have been able find anywhere else in the last two weeks! I bought this 93 AWD EXT over the summer with 139,000 miles.I pulled the rear interior and made it into a cargo van.This is the first one I have owned and really love it. Of course it needed some work when I bought it from a co worker who does not like to service or take care of anything.The problem is the front wheels are not pulling. (Found this out stuck in snow in my driveway) When I changed the transfer case fluid it smelled a little burnt. I have jacked up one side of the van, have it in gear, idling and can get the front wheel to spin if I help to get it going with my hand but can grab it,stop it and turn it backwards while the rear is still spinning.( I can feel a little resistance when I do this but not much) I have watched the front driveshaft and that turns whatever direction I spin the front wheel. I have read a lot on here about the viscous coupling going bad and locking up but have not found anything about it slipping. Any suggestions?
Thanks

If the front drive shaft turns freely the transfer case is trashed. I have seen this happen to one other BW4472. It was sandfly Bob's and he was a little stuck! LOL With the tranny in park and the front tires off the ground, the front drive shaft should not turn any more than a very small amount. Time for a new/used one or a 2 speed t-case swap.

LOL, great pic of Bob's van