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Unleaded 88, Is It Ok?

MikeG

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They recently built a Casey's near me. I stopped in the other day to get gas and they sold 87, Unleaded 88, and 91, but no 89. Since I didn't know much about the Unleaded 88, I paid the higher price for the 91. From what I understand, the Unleaded 88 has 15% ethanol compared to 10% for the 87 and 91 octane fuels. Does anyone here run it in their trucks, and if so, how has it done? Does the extra ethanol matter much?
 
First off its not the 60s all fuel is Unleaded no need to add that lol, second off no fuel can be sold with more than 15% ethanol other than e85

The only difference would be with the extra 5% ethanol you would burn through it a touch faster
 
Unleaded 88 is what they call it. From what I read it is the way it is distinguished from the 10% ethanol fuel.

So it may cost a little less but you'll burn through it a bit faster than 89 octane from another station
 
First off its not the 60s all fuel is Unleaded no need to add that lol, second off no fuel can be sold with more than 15% ethanol other than e85

The only difference would be with the extra 5% ethanol you would burn through it a touch faster
FWIW, AVGAS is still leaded although the FAA is testing unleaded alternatives.
 
Unleaded 88 is e15 I believe
Use the 91 out of those options

don’t know if you have any experience with ethanol or e85 but the stoichometry or air/fuel ratio on gasoline is 14.7ish:1 and on e85 it’s closer to 10:1 so you use ALOT more of it. It’s cheaper because it’s more corn and less gasoline

E85 flex fuel vehicles can make a little more power on the higher octane fuel (I think my Ford was rated ~30 hp more with it) but they get awful mileage running on it.

Your truck is not flex fuel btw. Max 10% ethanol. I get ethanol free fuel when I can find it for both my Ram and my 944. I’ll put mop water in my Toyota Idc lol
 
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As others stated, 10% ethanol Max (most places put 10% in). I’ve put regular (85 here at Altitude) and it runs fine, but usually run midgrade . This engine is designed to take regular or migrade, since it’s just a truck... i think the car version (392) requires premium.
 
Thanks y'all. I normally run 89 and the occasional 91. I just wasn't sure if the higher ethanol was an issue.
 
FWIW, I checked the owner's manual for my 2020 on a whim and found this. 15% ethanol is apparently acceptable for the 2020 6.4 -- not that I'd run it.

Screenshot 2021-07-26 222745.jpg
 
Weird my 2019 calls for 89 either way I prefer e0. Nothing against farmers but corn is for tortilla chips.
We now have a Murphy's just 3 miles down the road that sells E0 (0% corn) gas. I run it in all my small engines and the SeaDoo boat. The Audi requires premium so that's wherever is cheapest which usually means the local (discounted by grocery points) King Sooper.
 
Weird my 2019 calls for 89 either way I prefer e0. Nothing against farmers but corn is for tortilla chips.
I'm with you on the E0. Unfortunately, there are very few places around me that still sell unadulterated gasoline -- just about every place is 10% ethanol now. When I do get a chance to get a tank full of *real* gasoline I relish it.
 
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