I think it's brake noise, but I can't rule out it being a tire. 2016 Dodge Durango R/T, 18k miles, just got back from a round trip from Pittsburgh to Atlanta and back. I noticed coming down mountains that I'd get a thump-thump-thump noise but only sometimes when braking. It tended to be more noticeable during straight line braking than around curves. Despite the noise, I felt nothing in the steering wheel (like a warped front rotor would do) and very little real vibration, though there was some, connected to the noise. Does this sound like a rear rotor? Or possibly a bad tire? Sometime it almost felt like the rear had a wobbly tire in some curves (and the tires are crap Bridgestone Eco somethings) though I can't notice anything from looking at the tires. Any thoughts? What type of parking brake setup is used? Is there an internal drum or does the parking brake use the discs? It's a Certified PreOwned, not sure if any of this falls under the CPO warranty.