It looks like the oil filter, when the engine is off, sometimes drains back to the engine, other times it does not drain to engine. There is a small hole in the center tube of the filter cannister, near the top of the filter, to allow oil that has passed through the filter to enter the tube and drain to the engine. I don't see a hole low on the tube but this morning the oil level in the cannister was near the bottom of the filter. A few days ago the cannister was near full. Both checks were with a cold engine after sitting overnight. A few days ago the dipstick showed oil down about 3/4 of a quart (cannister full) and today it was overfull by 1/4 quart (cannister near empty). looks like I will need to remove the cannister, clean it and check for a leak point into the center tube near the base.
