I changed the oil 600 miles ago to Mobil 1 ep 5w20 and in 600 miles it's dropped half a quart. I thought maybe the timing cover was leaking again since it was recently replaced but nope. Nothing is leaking anywhere.i know it's said on here switching brands sometimes the engine will use the new oil for a little while. But half a quart in 600 miles seems excessive. When I ran vwb it didn't drop at all in 4000 miles. So what gives?