There are a few relays on the path to the tranfer case and I think one is the expensive gem module. I would do an advanced search on it. If you can't turn the front driveshaft in 2wd with tires on the ground and hubs locked you should be OK in the mechanical part of it from the trans case forward.
This forum is owned and operated by Internet Brands, Inc., a Delaware corporation. It is not authorized or endorsed by the Ford Motor Company and is not affiliated with the Ford Motor Company or its related companies in any way. FordŽ is a registered trademark of the Ford Motor Company.