Transfer Case problems

Couple months ago my blazer got stuck in 2 wheel, shortly there after it got stuck in 4 wheel.  I replaced the motor on the side of the transfer case(twice, did it myself), and that did nothing.  At the moment i am running it with the front drive shaft off, i shifted it into 2 wheel manually.   Im pretty sure it something electrical but dont know what to do.  any help would be great, thanks.

It could be the vaccum switch on the top of the transfer case, or a bad vaccum hose leading to the switch.

Here's  thread on it

Here is a how to that has info on how to remove and replace stuff, plus diagnoise your problem.

Hope it helps.

-Lenny

thanks for the help man, Ill give it a shot