[GrannyJ]

I have noticed this on concrete sections of highway but no problems since I added the camper shell and have my wooden platform and dog crates in the back at all times.

No feeling of loss of control but felt pretty queasy when it did happen.

Now that I am aware, I have been watching other trucks though and I see them doing it. I can tell if my bed is moving because I am looking through dog crates - the only time I really noticed anything on normal roads was slight motion while I was sitting in the backseat ....