I have ran WMO from a variety of sources in my 300SD. It is unknown to me if it is synthetic or not. It did come from some sort of Diesel engine, though. I blend with 15-20% RUG and let it settle for a few days before filtering it down to 1 micron and adding it straight into the fuel tank. It runs well with a slight increase in smoke and coking. The adverse effects of running petro fuels seems to be much less than with running vegetable or animal fat based fuels. I have a 300SD that was run on WVO and I am very close to suspecting IP failure. If replacing the delivery valves does not solve my idle problem, I am going to swap the IP after re-checking the motor mounts.

I know people who have run fully synthetic oil in an OM617. I have not done it consciously, so I can't give first hand experience with it.

__________________
1991 F250 super-cab 7.3 IDI. (rebuilt by me) Banks Sidewinder turbo, hydroboost brakes, new IP and injectors.
2003 S430 - 107K
1983 300SD - Tanoshii - mostly restored ~400K+.
1983 300SD - Good interior. Engine finally tamed ~250K.
Monark Nozzle Install Video - http://tinyurl.com/ptd2tge