Hello. I have an 07 Dodge Nitro with the 3.7L engine and it's 4X4 and has 61,000 miles. About a week or so ago it started to make a light metal on metal tinny kind of a noise and I haven't been able to pin point it. Now it is louder and I believe it's coming from the pass side rear area. It's like a "rotational" metal-on-metal noise and it comes and goes. It doesn't happen all the time. Sometimes it's a light noise and other times it's really loud. I was thinking it was an exhaust shield or something but can't see anything. Any thoughts? Thanks for your help!