I use Mobil 1 10W30 fully synthetic and last changed the oil about 4K miles ago. I did a change this morning using a full four quarts again. The problem is this: when I moved to put the used oil into the old quart containers, I only filled two quarts! I put in four last time...
The BUR hasn't been marking it's territory nor have I seen any big leaks. Using 2 quarts of oil over 4K miles seems a bit much... any clue as to why it's disappearing so?