Can I fill half a tank of e85 if I have standard e10 86 octane in the tank already? Yes, my 08 is a FFV.

 

yes

 

Here is what my 13 manual states:

"Choosing the Right Fuel With a Flex Fuel Vehicle (If Equipped)

Note: If your vehicle is flex fuel capable, it will have a yellow bezel
placed over the fuel fill inlet.

Flex fuel vehicles are designed to use unleaded gasoline or an ethanol
fuel blend that contain up to 85% ethanol. It is also acceptable to use
any mixture of unleaded gasoline and ethanol fuel that contains up to
85% ethanol. An ethanol fuel blend that contains 85% ethanol is labeled
as E85 at the service station.

It is best not to alternate repeatedly between gasoline and E85.
If you do switch fuels, it is recommended that you add as much fuel
as possible—at least half a tank. Do not add less than five gallons
(18.9 liters) when refueling. You should drive the vehicle immediately
after refueling for at least 5 miles (8 kilometers) to allow the vehicle
to adapt to the change in ethanol concentration. If you exclusively use
E85 fuel, it is recommended to fill the fuel tank with regular unleaded
gasoline at each scheduled oil change."

 

Thanks. I wanted to try it out to see how underwhelmed I would be.

 

If it were a Buck 50 a gallon you be pleased...

 

Just as an FYI, I ran e85 in a Tahoe one time. It never ran the same again. A different vehicle I know but...............................

 

e85:

Pro: Beast Mode

Con: mpg

neither: cost-per-mile really didn't change much the last time I tried it, might have been a penny a mile cheaper to run the e85. But: That was last winter in MN, and that might have actually been closer to the e50~ish mix you're about to run.

 

Just stick to regular gas unless its about $1 per gallon.... Even at $1.50 you are probably not breaking even. The one time I used it in my Ranger years ago I lost about 30% of my MPG with no noticeable performance gains. There's even less of a reason to use E85 in Illinois now anyway since the tax breaks for it have now been lifted (or will be soon).

 

Only beast mode if your truck is tuned for it. It packs less BTU potential than 100% pure gasoline and requires more fuel to go the same distance than if you used regular gas. It is a hot fuel for those with forced induction.

 

It would have to be under $1.00 per gal for me to use it.(paying $1.96-for reg unl now) When I lived in WI-it was about 0.50 cheaper due to state tax aid. My owner's manual says if it is used 100%-the oil change interval goes down to 3000 miles and plugs have to be changed sooner. It appears to be a bit harder on the 5.4L. To date-no E85 has touched its tank since new


06 Supercrew Flex-fuel 6.5 ft bed 3.73LS, trailer tow pkg.