Im pretty sure all normal unleaded has ethanol in it these days and as for seperating i have heard it does that but i have put some ethanol feul in a see through container that,s about 6 months old now and i have,nt seen any separation of the two feuls yet.I use it in my boat and have had no problems at all i also recall many years ago pulling up to a country service station and seeing super with ethanol i dont want say that it doesnt cause problems but why arn,t they building engine,s etc to run on ethanol blend feul because we are going to see alot more of it.