4x4 Problem

Ok Heres The Scoop.95 4x4 I Lost My 4x4 And Cantseem To Get It To Work Has A 4.3 Auto Trans Push Button 4x4.i Was Told To Unhook The Battery,i Did And Rehooked It Now I Dont Have Any Power To The Switch Ecept When I Turn The Key On An Thats It,also I Am Stuck In 4lo And The Truck Revs Real Hi And I Cant Get Over 20 Miles An Hour It Revs Around 6 Grand And Doesnt Seem To Move Very Well????????????? Whats Up With Thismerlin Help!!!!!!!!!!!!!! Thanks Man