I have an '07 JK 6 speed w/45k on it. I have the doors/roof off and have occasionally noticed a sound. The sound happens after I release the clutch and before the JK starts moving. It sounds like metal banging into another piece of metal. I have driven a manual trans all my life (30 yrs behind the wheel) so I am comfortable w/a 6 spd. The sound is only happens occasionally. It isn't a loud banging sound but I'm concerned there might be a transmission issue. I just had the 45k service done and the tech said it looked like the throw out bearing might be on the way out. Should I be worried about the noise?