Hi there. Since I got my car I broke it in for 1 year or so and started using M1 and I noticed that I have about 1 litre oil consumption every 3 000 miles. Also when I parked the car I smelled burned oil all the time. No oil leaks no were, went under the car and looked all over. So I went back to Castrol GTX, right now no consumption and no smell. But I want best protection for my car, but not sure what should I do right now??? I used M1 for .5 years(5 oil changes) and Castrol GTX right now for 2 oil changes. By the way car is 2001 Subaru RS. Please reccomend something!!