We carry extra fuel and gas on our receiver hitch cargo tray along with our generator and I didn't like the wobble either. Fixed it by having our local camper friendly welder add a bar on each end of the tray, buttons on the bumper same as our Hapijack tiedowns use, added a pair of Derringer fast guns and stopped the flopping. Helped our steps that are built into the cargo tray become more stable as well. Killed two birds with one stone. The tray even has a receiver built into it for the bike rack. I know, I know, pics. I'm way upload and link challenged. Can handle email attachments, usually.