What is the generally accepted timing chain service interval for M110 inline six engines? This one is an '85 euro model with 159,000 miles and religious maintenance for all of those miles. It runs smoothly and does not make any odd noises other than the usual clicky (recently adjusted) mechanical valvetrain. Are there any warning noises or other signs to look/listen for? When replacing the chain, do guides and/or sprockets also need to be replaced? How much of the front of the engine needs to be dismantled to do the service? (It is in a 107 body) As always, any advice would be much appreciated.