My 03 2500 has some issues with the transfer case. It has a vicious grindy noise in 4wd. It will hammer & bang while turning or torqueing into it. Driving at a steady pace on the road it sound like a train car ( clickity clack). Switch it back to 2 wheel, not a peep out of it. Its a np273 with electric shift. I'm thinking wore out shift collar maybe? Anyone else had this?

 

Sounds like a stretched chain.