This is actually responding to a point on another thread.

I remember asking MB if I should go with synthetics on my SLC, and the general consensus of the service advisors at the 800 # was no. (This goes back a few years.) I also remember some articles in Car & Driver in the early 90's which said the same for cars for which it was not the approved oil. Something about the particles being too small for the filter or something. (I forget.)

Are you using synthetics? I'm specifically interested in the 450 engine, but I'm interested in all feedback.

My car does not get driven much; about 2K miles/year.