I too have the clunk, build date 7/18. I feel it more than I can hear it, underneath my left foot. Had the issue since I picked up the truck. I was concerned about how I was going to explain this issue to my service department, so I thought I would look on this forum first and found this thread. Thanks a lot Delmonico_19 for making my life a whole lot easier. Now if I can get the excess wind noise issue from the drivers side door fixed I will have a perfect truck. Love the truck even with these two issues.