My wife has a 2005 D with big block 5.7. About 3-4 months ago when weather in Oregon started getting colder it started to make a noise from the undercarriage that can be best described as metal on metal although it was difficult to tell if it was from moving parts or those in close proximity to one another. The noise can be exasperated by A) Turning the wheel, B) hitting bumps on highway C) putting into gear and out of gear (more noise in Drive less in Park) D) mostly happens when the weather is cold. It goes away after a few minutes or when car is warm. We've had it to the dealership 2X so far and the first "Fix" was to top off the power steering reservoir which did nothing but temporarily satisfy the dealer and ourselves. The second time they troubleshot it to the exhaust saying we hit something (My wife hit her bumper on my daughters acura bumper and kinda stoved it in) The dealer said you can see marks on the exhaust where it was hit (Exhaust routed to right side of car from rear bumper stoved in on left side) and I have crawled all underneath looking for broken welds and even have shimmied underneath while wife starts vehicle puts in gear out of gear and moves tires although each time I crawl underneath the problem is not there to be heard! Very irritating. I have boycotted my current dealership because no issue that we have broght them has been fixed in one outing and being an ex field service engineer for the semiconductor industry just looking at their technicians and talking to them at times scares the crap out of me like they are troubleshooting from a "Dodge Durango Problems for Dummies" handbook! I've searched many "noises" issues in this forum and see all sorts of potential the most of which is the expanding exhaust manifold which is making the noise until the metal expands and makes a good seal. I'll try that in a few... Anyways any input would be great. Thanks Kevin