Flex fuel,
My truck has the capability to use 85 grade fuel but after reading the manual, I'm not sold on putting it in my fuel tank. As per the manual, it states that if I use the 85 grade it has to be filled at least to more than half of the tank. Then it states that once I fill it up with this fuel, I have to immediately drive it for AT LEAST five miles! There were some other requirements mentioning the use of this particular grade, for example you must alternate back and forth with 85 and 87 but it's not recommended to go consecutively with 85 grade. So the questions I have for anyone is, what are your experiences with 85 grade? Is it worth using? Advantages? Disadvantages? I would really like to hear from the people that have used it in their vehicles several times.

 

Are you referring to E85? If so, this is 85% ethanol and 15% gasoline. Most 87,89 and 93 grades are 10% ethanol and 90% gasoline.

As I understand it, E85 doesn't have the cleansing affect that normal E10 gasoline has. E85 will also likely be less expensive at the pump and will also yield fewer MPG's. There's really not much to be gained unless you're a corn farmer.

 

Yes, I'm referring to E85. Why would they make it available for F-150's and the like if it's more harm than good? The only advantage I really see is cost at the pump, but it may cost you your truck down the road.

 

I have a good friend that works at the Ford plant in North Kansas City (ClayCoMo) and he's also vary tight with the wallet. He ran the E85 fuel and really gave it a good try. He said that it is cheaper at the pump, but that he got less mileage, and cost him some performance too. My 2011 F150 is a Flex Fuel vehicle, but I'm not even going to give it a try. And as tseekins mentioned, what about it's cleaning abilities?

Unk Bob

 

Like I mentioned, my buddy is really tight with the wallet. But once he found out what E85 did to the mileage, and performance, he was finished with it.

Unk Bob

 

Well Unk Bob, you've pretty much put the nail in the coffin for me using E85 in my fuel tank buddy. Thanks for the insight.

 

You are welcome

Unk Bob

 

at work we are encouraged to use flex fuel whenever possible. we have an e10 pump and and e30 pump, and we can buy whatever we want at the local stations, and i use e85 from time to time in the summer.

so here's my observations:

when using e30 or e85, there is a very noticeable increase in power. so much so, that, after using e30 for many many tanks in a row, when i switched to e10, i thought something was wrong with the truck. it just took a lot more pedal to get the truck to accelerate like i was used to.

you will also notice that your transmission shift strategy takes a few shift cycles to compensate once you switch fuels. when going from e30 to e10, it will shift rather harsh for a few shifts, and when going from e10 to e30 it will slip a bit when it shifts.

when using e30 or e85, the computer adds a lot of ignition timing to take advantage of the higher octane rating of the flex fuel. the resulting increase in power is very noticable, right off idle. Or at least it is in my 2010.

cleansing effects ... yes, the e85 is a very good fuel cleanser. it will be very effective at removing any varnish left in the fuel tank by regular gasoline. If your truck has 100k on it and has never seen a tank of flex fuel, then i wouldn't use it. the ethanol will dislodge all the garbage in your tank and cause problems.

if it is a new truck, i would use e85 once and a while to keep the fuel system clean. rather than using seafoam, or STP, or the like, just use e85 and it will do the same thing.

when switching back and forth, you should let it run a while so the computer has time to update the spark and fuel tables for the fuel you are running. if you go from e10 to a tank of e85 and don't give it time to update the tables, it may start very hard the next time. i've never had that problem, but i always fill up at the begining of the day, rather than the end of the day.

fuel mileage ... yes, it will go down.
on a straight highway run, on e10 i'll get mid 18's MPG
on e30, i'll get mid 16's MPG
on e85, i'll get low 15's MPG

generally, though, you can figure about a 30% decrease from e10 to e85. so if your price at the pump is greater than 30%, you can come out at a wash or better. but if the spread is only 20%, you will spend more per mile when using e85.

FWIW, my 2010 has probably only seen 10 tanks or less of anything less than e30.

use it if you like, or don't, for the most part, the truck won't care either way.

 

Good stuff there Mike- I didn't know most of that. Thanks for posting, reps sent! I'd like to try it just for comparison but don't think we have it around here that I have seen

 

Wow, that was very good detailed information. I don't know Mike, I guess I'll have to try it one day and see. I guess the biggest thing is weighing the pros and the cons to see if there is any benefit at all of using it.

 

Politics. Now you are wiser to the world.

 

That is a lot of good information. But for myself, I'd rather give a little more, and have quite a bit more, and I'm putting running better fuel through the tank. Same with the engine oil, better grade oil and filter = better protection. Just an old guy rule of thumb I guess.
Just my opinion.


Unk Bob

 

meborder, good info!

 

E85 fuel is made availble to lower the emissions output of the engine. I think it lowers the NOx levels.

 

I ran e85 a couple months ago and my mileage has never recovered I just did a 300 mile interstate trip today averaging only 15.6 mpg before the e85 I was getting 17 in town