Premium w/10% ethanol or mid-grade ethanol free?

[Roverfire]

So the local station I've been buying gas just recently switched their premium and regular to a 10% ethanol blend. Their mid-grade(89 octane) is still ethanol free. Should I run the mid-grade since it doesn't have ethanol in it or stick with the premium?

 

[thequickervicar]

I'm running 10% ethanol @ 87 octane. Seems ok to me. EVERYTHING around here has ethanol now.

 

[jafir]

Premium. Alcohol while not being as dense, and therefore lowering your MPG, actually improves the anti-knock rating. E85 (which you shouldn't use... or not much of it) has a AKI or octane rating of over 100.

 

[kferg]

Try it and see. Everything here has 10% and I do see a difference in mileage on both trucks since the change. Mid-grade or Premium make no differece to my mileage, best I can average is around 13, down from 14, hwy maybe 15.5 mpg on the right day, use to be 16.5 to a best of 17mpg without ethanol.

 

[thequickervicar]

Try it and see. Everything here has 10% and I do see a difference in mileage on both trucks since the change. Mid-grade or Premium make no differece to my mileage, best I can average is around 13, down from 14, hwy maybe 15.5 mpg on the right day, use to be 16.5 to a best of 17mpg without ethanol.

I used to run premium (93), but decided to try 87 in a pinch. No difference in running or mileage, so I switched permanently with no ill effects.

 

[Some Dude]

Must be a 3.9 thing. I've run 91 in mine since day 1. The few times I've had to drop down to 87 or 85 because I'm in the middle of podunk nowhere Montana or Wyoming and that's all they had - I could tell the difference immediately. The 4.6 shudders a little on low octane gas, especially on 85 at low elevation.

 

[Mongo]

I saw no difference in mileage when using any grade of gas on both the d1 and d2...can't wait for the wiki experts to start posting stating they get 18mpg on 91/93 and 10mpg on anything but the higher grades...not bashing but it's always a funny debate...

oh, yeah I average 25mpg in the 110...

 

[jafir]

oh, yeah I average 25mpg in the 110...

And we all hate you for it.

 

[pdxrovermech]

mid without ethanol

 

[mbrummal]

just remember the oil companies know that alcohol raises the octane and they adjust the additive content accordingly.

 

[ptschram]

Premium. Alcohol while not being as dense, and therefore lowering your MPG, actually improves the anti-knock rating. E85 (which you shouldn't use... or not much of it) has a AKI or octane rating of over 100.

I have run my trucks on E-42.5 with no problems.

When gasoline gets up over $4/gallon, the E-85 makes it hurt less, even with the reduction in fuel economy.

 

[ptschram]

just remember the oil companies know that alcohol raises the octane and they adjust the additive content accordingly.

Gasoline is such a dirty mix of compounds, does it really matter?

 

[rover4x4]

Ethanol is the devi

 

[smrover1]

I have been running e-85 for years hell i think it made the damn thing run better

 

[wheelen disco]

I got lean codes when I ran e-85

 

[jafir]

I have run my trucks on E-42.5 with no problems.

When gasoline gets up over $4/gallon, the E-85 makes it hurt less, even with the reduction in fuel economy.

I've never used more than a 1/4 tank at a time on my 96, but it ran fine. And when we only get 13 mpg, what's one or two mpg less?

 

[KyleT]

ethenol free for sure.

 

[no694terry]

About 10mpgs here but running superb on 89. Just pers down the highway. Used to run 93, no more

 

[BenDronsick]

Low octane will foul O2 sensors long term. Just sayin.

 

[jeffro0502]

Low octane will foul O2 sensors long term. Just sayin.

Based on?