Hey everyone I'm new here and was wondering if anyone could help diagnose a 4x4 problem.. I have a 2003 trailblazer ltz that four wheel doesnt work in.. The shift looks complete when you turn switch,no flashing lights, no service 4 wheel light. I crawled under it today I hear the transfer case encoder run, the front axle switch sounds like it's running and the front drive shaft does lock up. So it seems transfer case is ok.. Anyone had similar situation with theres??? Is it possible that it is the axle actuator?