I have used Mobil 1 Tri synthetic as well, but its in a MB 92 300D 2.5, 84 300D turbo, and 86 190D 2.5. I didnt take apart the engines in all of them, but from a breif look in the past, I didnt notice any deposits. They claim it doesnt cause engine deposits, but it probably does cause some, but much less than with conventional oils. If you use some engine cleaner every 50,000 miles, it should remove all of it.