1989 Bronco 4x4 Problems

I have an 1989 Bronco with a push button 4x4. When I push the 4x4 button, (yes I said push button) it will transfer into 4x4 then after a min or so the transfer case will slip into neutral and I am left reving the engin. I have to then shift into park then hit the 4x4 button again, it jams back into gear then I can shift back into dive and go in 2wd. Any ideas on what is causing this to happen.

Go to this forum these guys know something about Bronco's unlike this forum. http://www.broncoii.org/

That is a Bronco II site. I don't have a Bronce II, we talking about two different vehicles here. Cummon, Someone help me out here.

go to this forum

http://www.fullsizebronco.com

Some great guys and gals, and some awesome info. Ive never seen a better bronco site than that one.