Guys if you really want to treat your diesel special then add a bypass filter to your MB and run synthetic Delvac 1 or Amsoil series 3000. One of the reasons the big rigs don't change their oil as often as we do in our own cars is that tend to only change their primary and bypass filters then top off with additional oil to compensate for oil lost during filter change. Some of these rigs may go up to 100k before they change all their oil and filters. I am not suggesting any of you try the 100k scenario, but if you are really serious about the longevity of your diesel then I would seriously look at adding the bypass filtering system to your car in conjunction with the primary filter. Johnny