Full tank of gas by chance? It's pretty common to have a passenger lean.
That would be my guess as well. Almost every JK and JKU I have seen in person does not sit level to some degree. How bad is it? My JKU does not sit level, but itss hard to tell just by eyeballing it. The measurements are the tell tale.
Yup, very common on a jku and it's been discussed a few times. My JKUR sat 1/2 in lower on the passengers side with the gas tank empty and full both stock and lifted. It drove me crazy so I put a 1/2 in spacer in the passenger rear and problem solved. You can also use adjustable rear sway bar links and adjust the passengers side larger then the drivers side.