I don't know what volume of oil the engine is overfilled by. The distance between the min and max marks on the dipstick is about 9/16 of an inch and this is supposed to correspond to 2.1 quarts. I was referring to the oil level of the dipstick being 1/2 an inch to 5/8 of an inch above the full mark. If the level is directly proportional to the volume of oil at this part of the sump, that would mean a 2 quart overfill! The car now has 65,000 miles and has had the correct amount of oil in it only once, when delivered from the factory.