locked in 4 wheel low. service 4x4 light on

Can not use the truck. The transfer case is stuck in 4 wheel low. Can not get it in 2 wheel mode. Worked fine until November 15 when I pulled into a drive way turning the wheels hard right, when leaving, The truck acted as if the brakes were pulsing , very unnerving. Once I got the wheels straight it seemed to be ok. A few miles later, A service 4x4 light came on and shortly after that, the 4 w low light came on and the engine started racing and making strange sounds.( almost sounded like moaning). Since then, I can't use the truck.