I've read a lot on this site but have never posted. In the past few weeks I've heard the new Duramax and Powerstroke Diesel engines. I have a 2004.5 Cummins in my 2500 and I thought it was much more quieter than the other 2, but I'm almost thinking it's the loudest of the 3. Have any of you heard all 3? Which do you think is quieter?