Me too!! I have this problem! Very annoying.
Usually happens in cold weather also. it sounds like something is vibrating around in the dash(thought it might be some wiring rattling around) Only happens in my tour when it shifts into a lower gear though.
I've driven it twice w/ the dash ripped apart and no noise, tighten everything up, put it back together and it's back. Funny thing is it never used to do it. Go figure
