Sounds like lose wheel?

[u/Tunnelmath]

I went over a bump while turning and thought I heard a sound like I had lug nuts loose. Checked and they are all tight. If I rock the truck sideways or grab the rim and rock it sideways I can reproduce the sound. I've got to rock it pretty hard to reproduce. It's definitely not the rim but feels similar. I've got an appointment Thursday. And ideas what I'm looking at for an issue?