Greetings Wilton,

When I first got my Benz, which by the way has the 300D engine, but non-turbo it used about the same quantity of oil, and I scratched my head over that one for quite a while, and went though various posts trying to figure out the problem. It was in front of me the whole time but appeared invisable. Although all vacuum operated systems worked perfectly, the slight tear in the vacuum pump rubber diaphragm was sucking oil from the engine on the outward stroke and sending it via a slight steam to my intake manifold where it was being burned. After replacing the diaphragm my consumption went from a quart every 250-300 miles to now about 3/4 of a quart in 1650 miles. I consider that liveable considering that I know where most of that oil is going now is out the rear oil pan seal that seems to constantly seep. If I had the time and the equipment to pull the engine up in the chassis I would replace the seal and most likely pick up the biggest part of my lost oil. Hey, if there's someone out there that knows an easy way to replace a rear oil seal let me know. I would assume that if you change the rear, you screw up the front so it will have to be replaced as well.

Good Luck Wilton, keep us informed on the outcome.

Charles