I've only put gas in once since I've only had my 07 SM for about three weeks. It was embarassing. Took me a couple of minutes and a lot of force to get the cap off. I thought there might be some extra push/pull/twist action that neither the dealer nor the owner's manual mentioned. Don't know what it will be like next time. I only snugged it up and it came back off ok. I've not tried it since then. We'll see (probably this weekend).
Gary
