I have been on the wire for some time about the use of ethanol based fuels. I think the savings gained is lost by lower mileage and power I have always been concerned about the fact ethanol is a cleaner and unless your vehicle is newer it can break loose gunk and cause all kinds of problems. In addition it can cause a breakdown of gaskets and seals. Further research has been done on the forming of formic acid, an E-85 byproduct, and unless the correct oil is used it can cause major problems. So with there being no advantage including not saving dollars I am not recommending the use of ethanol based fuels. If you insist on using it I would not recommend synthetic oil and would change the oil at 3000 miles regardless of the manufacture recommendation.The only reason I used it in the winter was I thought it helped with moisture in the fuel tank but that is incorrect.