A genuine thanks to the guys who took the time to mention the dampener. About a month ago my 2010 started clunking going over small sharp bumps, and short dips in the road. The noise was definitely metal on metal. I couldn't get into my local dealer in less than a week, so took it to another dealer out of town. 150$ for them to tell me it 'sounded like a normal raptor'. I wanted to be sure it wasn't something way more serious. After reading this thread I flopped around like a whale under the truck, making use of the epic ground clearance for my fat ass, and found my dampner is flooping around like a dead fish. I found the dealer missed my loose swaying spare tire, off center on the hanger, fixed that too. After wedging balls of duct tape around the dampner the noise ceased. Off for bailing wire or zip ties tomorrow, then a big saw when I feel ambitious. So nice to get rid of that damn noise.