Loose / Shaky Tailgate

I love my 08 regular cab - it drives like a sports car and is super solid going over bumps - not a rattle or squeak. EXCEPT FOR THE TAILGATE! Argh, the side that slides out for removal is loose on the bottom and so it rattles like a farm truck going over rough terrain. Does anyone have this problem or is it just me? I'm assuming this is rare because I never found threads about it when I figured out what it was a couple years ago. I had a camper shell for awhile and that eliminated the rattle, but I sold it so now it's back - I'm also going to be selling the truck eventually so I don't want to lose money on this issue.

I figure I could swap tailgates for a few minutes with someone to see if it's the tailgate or the mount (?) that is out of spec. I'm thinking of finding a big rubber band or something and lubing it up to act as a cushion on the mount, but eventually this would obviously wear through and not be a permanent solution - not something I want to do if I'm selling it - I don't like having a list of things to explain to a potential buyer so I'd like a permanent fix. Any suggestions?

 

I have not looked that close at mine but have you researched to see if theres a bushing that's maybe missing?

 

There's no bushing on the other side and I never found any threads concerning this yet