If I wanted to get the ultimate gas mileage from my econobox 1.8L BMW, would it be advisable to use a 0W-20 oil like M1?
BMW has changed the recommended oil viscosities for nearly all its engines, old and new, to synthetic 5W-30, so would going one grade lower be dangerous?
BMW has changed the recommended oil viscosities for nearly all its engines, old and new, to synthetic 5W-30, so would going one grade lower be dangerous?