so my z was making a rattle in the rear by the drivers side wheel. i took it in and the dealer "could hear it, but couldnt find it" and gave it back to me. so a friend of mine works at wal-mart in tire and lube express. i stopped in to get my tires checked out cause i had a slow leak. he hears the rattle and starts looking. turns out when the dealer did my recall on the fuel lines and dropped the exhaust, they forgot to either put a bolt on the hanger by the rear wheel or didnt tighten it down. the rattle was the hanger hitting my exhaust. it's sad the dealer didnt find it, but wal-mart did.