Last night my 03 3500 started making this kind of grinding noise whenever I turned it off, nothing real serious or loud, just enough for me to hear and annoy me. I should mention that I changed my serpentine belt a month ago or so. I should also mention that I live in Indiana and we have been having some snow and of course they paint the road with salt. I read in some other forums that the 5.9 will rattle or something when salt hits it, i don't know much though. Has anyone had a problem like this and should I be worried.