I have a 05' Suburban with 5.3 and having problems with 4x4 system again. I have no control of 4x4 system, it goes from 4lo to Neutral to 2high by itself just by shutting down truck & restarting or disconnecting battery. I also have 00' Tahoe with 5.3 with "service 4x4" light on, I have to use truck more to let you know whats going on with it exactly but there are no lights at switches. The problem is that my 90' Suburban has no issues with 4x4, but there are no switches! Any help would be appreciated.