I want to use the Rotella T6 5w-40 in my Scag with the Vangaurd 37HP. My concern is the Rotella doesn't have the API SN rating, only API CK-4. It also doesn't have the "For Gasoline Engines" I know a lot of people including myself who use it in ATV's. Below is from Vangaurd for this motor. Is...