I recently drove through New Jersey where they pump gas for you (which I kinda hate) and they didn't tighten the cap enough and the same thing ended up happening to me a few days after the fill up.
2005 V6 Limited 110k miles. $10,500 January 2013.
She's a 2wd but it's no big deal. My first 4runner and I love them now. Working on getting a 4th gen 4x4 one day.