Warden, that's what I'm after - do you know if the MB coolant has an anti-cavitation additive? I know Ford now strongly recommends periodic and frequent addition of a seperate anti-cavitation additive for trucks with the powerstroke diesels - due to their tacit admission that the excessive erosion found in some of these trucks water jackets should have necessitated the use of better coolant that they now use. I really do not know specifically why the MB OM 6xx engines may be less susceptable to cavitation erosion than other engines (thicker walls, different metallurgy, injection pattern?) Can you shed some light here?