85 or 88 (1 Viewer)
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I’d go 88 instead of 85. No real benefit to use 91 overall besides maybe a horsepower or two and a lighter wallet
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Thanks I never seen 85 and 88 so just went with the familiar haha
What state was this in, and did the 85 say “ethanol free”?
I’ve seen this in AZ and UT, and it’s supposedly better than the higher octane with the crap mixed in.
No clue if true
I recall the 85 ethanol free, being close to same price as 91
I’m usually in my diesel when I’m in AZ or UT so never tried it personally
kcjaz
SILVER Star
IMO, ethanol free at any octane is better that 10% ethanol. The truck will run anything from 85 to 91 ethanol free or up to 10% ethanol. I go out of my way to find ethanol free and will pay premium price for it if I have too. It make a 15 to 20% difference in mpg. It’s not always worth it from a cost perspective but I’m more interested in the range than the cost.
I run 85 all the time in high altitude locations like Utah and Colorado. In fact, my consistently best run of MPGs was using 85 octane driving from Helena, MT to Moab. No idea why.
85 is just regular unleaded in the mountain west. It has ethanol and it works fine.
ALL the 85 I saw in Utah was a blue button (not yellow) and said NO ETHANOL in large letters.
Utah
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In Moab!
Looks like 85 is fine from the comments. However, the 85 is strangely expensive, the 91 is just a tad bit pricier. 88 was the cheapest. Very confusing!
Yes, my same experience, also in Moab and basically all of Utah.
Talking to some buddies with big $ fancy sports car, they always use and fill up with the Ethanol Free 85 when they see it
The station closest to my house sells ethanol free and I take advantage of it. It’s either me or the lawn care guys filling up for their equipment at that pump.
In that case the 85 was probably ethanol free.
I have lived in Oootah for decades 85 is normal. Ran it in my T100 for over two decades and now my LC. It burns goodly.
Some states sell 15% ethanol during the winter and 10% ethanol in the summer. Some states sell ethanol free.
Some states sell 15% ethanol during the winter and 10% ethanol in the summer. Some states sell ethanol free.
Yup. I live up near Park City and our prices between 85 and 91 have been very tight for about 7 years. I think I noticed it tightened up around 2017. Generally its only 15-20 cents between grades. So 20 cents from 85 to 88 and 20 cents from 88 to 91.
Because of this, I only run 91.
Thats not been my experience living here for 10 years. I have not seen ethanol free 85.
What I do see is 88 E0 at some of the Sinclair stations, or sometimes 91 E0 in areas where people are often bringing dirt bikes/ SxS's/sleds. The Chevron in Wellington, on the way to Moab from Spanish Fork, has 91 E0 at the pump and its obnoxiously expensive and I never get it.
Dont do this if you are super or turbocharged.
No. 15 to 20 cent spread between grades are common here. Its usually only 30-40 cents going from 85 to 91.
Go higher, not lower.
I use ethanol-free 88 since it is available right down the street. FWIW, I have had less issues with the ever popular gas fumes venting (read none so far but I doubt it will remain that way) using this gas than I did when using 88 or 91 w/ ethanol.
Except it isnt. Using a lower octane in a higher compression engine will result in knocking and eventually failure.
Now for same octane rating, there is not much difference. Gallon for gallon, ethanol free delivers 100 units, while E10 delivers 96.6 units of energy.
How much of a premium are you willing to pay for 3.4 units of energy? It is easy to do the math to see if it is a bargain, but most ethanol free pumps are overcharging significantly for that extra 3.4.
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New to Colorado? Hard to imagine you've never seen 85 before 
This. And the ethanol has a higher heat of vaporization and so it will cool the air charge and cylinder more than non-ethanol fuel and I dont believe that is captured in the octane rating.
