What was done to your JK this week?
i had the same issue when i had my 33's on there but i just let it go and i didn't have a problem, but since i moved up to the 35s and there is allot more weight i needed to do something about it until i could afford a rear tire carrier, and these are only staying on until i grab some of the daystar stops
It isnt so much a matter of the rattle it just evens out the stress of the heavy tire on the tailgate that is sticking out more than the stock tire and rim were. Trust me you will notice your tailgate starts to look like it is bowing out.
Went to the Spring Texas Spur Jeep Jamboree and made my Rugged Ridge XHD bumper into a stubby. 
Bent one of the end caps enough that it would rub when flexed and I had to remove them.

Bent one of the end caps enough that it would rub when flexed and I had to remove them.





