thank you for your reply
actually i am not that eager to change it (more money in the pocket) it's just that i read a post somewhere that recommanded changing timing belt/chain every 80k and my is way past that. now i will take your advice and let a dealer (not even a outside mercedes shop) change my timing chain. what are some signs to look for when i needed to change it (i will have the stretch checked out next weekend i promise). thanks blackmercedes