I get about 365 miles on about 12 and a half gallons, with mixed city and hway driving. I havent yet filled up on a completely empty tank. How empty does it have to be til the gaslight comes on? I let it get slightly below the E before i fill up but the gaslight still doesnt come on and it was still only 13 gallons when it hit automatic shutoff, so i dont see how it could be 17.1 gallons totally empty