Transmission or transfer case problem?

[Bobby G]

I have a 2005 Yukon. For some reason the truck will just go into neutral while I'm driving on the xway, backing out of my driveway, or leaving a stop light. I then have to press the AWD button on my dashboard to get it going again. When I do, I hear a slight grinding noise and then a loud "thump"... When it goes into neutral, the 2WD light is still lit.... Once I'm going again I can push the 2WD button and it accepts it.. Any thoughts???

 

[BobLin]

Bobby G, I have the exact same problem... In a 2005 Yukon... It just started yesterday... I don't see an answer yet. Have you figured it out? Mine also will not shift into 4L, and I can't put it in neutral ...