What is the average oil consumption of an 86 420SEL with 180,000 miles? I have noticed what seems to be a rise in oil consumption so I have started to track it. It hasn't been going on long enough to say it is a problem. Yesterday I had to add two quarts, and I check my oil every week. I park the car in the same spot every day and there is no oil under the car. The oil filter housing seems to have a very thin coat of oil on it, but does not look like a big enough leak for two quarts in a week (60 miles of driving). I have not had too close a look at the engine itself, and thanks to daylight savings time it is already too dark to look tonight. Has anyone had any experience with this model and excessive oil consumption? Before this it was arount 1 quart for 1000 miles, acceptable to me. What probable problem areas ahould I be checking.