Originally Posted by rtaylor2024
My truck is flex fuel and I was wondering if you can mix the two and which one is the best to use
Yes you can mix gas and ethanol. Flex fuel vehicles can run any mix from pure unleaded gas to 85% ethanol. The highest ethanol percentage you'll find at a pump is 85% which is E85. Some stations have what are known as blender pumps and will allow you to choose how much ethanol you want. (example: E20, E30, E50, E85). The number after the "E" is the percentage of ethanol. If you want a specific bled and don't have access to a blender pump then you can mix it yourself. Say you wanted about 50%, then just fill up halfway with E85 and then pull up to the gas pump and finish filling the tank with unleaded. I know a few people who claim to get better MPGs running in the E20 to E30 range, but I have not tried it myself, I run E85. Weather or not E85 is cheaper to use than gas depends on the price of both E85 and gas. You will lose a few MPGs on E85 but if E85 cheep enough in your area it might be cheaper in the end. In my area E85 is just cheap enough for me to break even (costs me about the same to run E85 or gas.) E85 will NOT hurt your flex fuel engine it was designed to run on it. However put E85 in a non flex fuel vehicle or worse a boat or lawn mower then get ready for a poorly running engine, let it sit unused for a few months and have fun cleaning the gummed up fuel out of everything. Oh wait, gas goes bad if it sits too long also. E85 burns cleaner and produces less emissions than gas, so running E85 will actually keep your engine cleaner inside. I've been running on E85 for months and have have no issues what so ever. My trucks runs great and starts rights up every time. Also I've noticed something I didn't expect, My MPGs drop less when towing than they did when I used regular unleaded, perhaps that has to do with E85 being 105 octane. You also gain 10-15 horsepower and LB-FT torque on E85. As for which fuel is better, that depends on why you are interested in flex fuel use. From an environmental standpoint E85 is better. From a cost standpoint it could go either way, but most likely gas will be cheaper.