Hello, I saw a resent thread on this site that goes over my question of what oil to use. I see people say Rotella and Delo400 and the grade 15w-40, 10w-40, 10w30, 5w40. I'm not sure which one to go with grade wise. I'm located in Florida with average temps 70-75°F (21-24°C). Summer is usually a little hotter than 75F, and my surf is a daily driver.