For the last 5000 miles or so, have heard a strange metallic clanking sound when loading/unloading the driveline. It wasn't the typical thunk/clank when accelerating from a standstill, or when coming to a stop. It was when at speed, and getting on/off the gas pedal. At first I assumed it was my hitch. It started happening more frequently and getting louder. Took the hitch out, and all of the stuff in the truck bed out. The noise continued to get louder and happening more often. I eliminated every possibility I could think of. I mounted the license plate better, made sure the spare tire was tight, checked for loose pieces underneath the truck. Got to the point where it happened every time I got on/off the gas. It is currently at the dealer. They think it is the drive shaft. They said the noise seems to transfer from the front to the rear, when letting off/getting on the gas. Hopefully this fixes it. Will let the group know when the noise is resolved.