HardcoreFx4

I have ran 87 before and I did it just because someone told me to and they were with me so I said ok I put $20 in hit the trip odometer. Than that ran out so quik it wasn't funny. So I pulled back into the same gas station put $20 of 91 in. What do you no I got like 5 to 6 mpg more. And when I first got my truck that's all the guy ran it would barley even burn squeal the tires. Put a few tanks of 91 in and she smoke em for a block.

questions. have you guys even ever ran 91. Or are you to cheap? Do you even change your oil on time? If you ask me its like running dollarstore oil or good brand oil.

Wolvee

What counts is not necessarily the Octane but the Ethanol %. I can tell the difference in as little a 8% & 10% Ethanol. The higher the percentage, the less efficient it will be.

If you can run 87 Eth Free, do it. That's much better than Premium w/ 10% Eth.

The difference in economy and premium in a non modified ecu is very minimal since your Air/timing isn't advanced or optimized for the longer fuel burn of the higher octane.

The ONLY benefit you can get from running premium in a non tuned engine is that it can help break up carbon & gunk on your valves. ..it can also make more if you're using crap gas. I run Sunoco super premium once a month and I see about .5+mpg in MPG but my monthly +/- variance is 1.5mpg so it's kind of a moot number.

Final point: What really matters is how you drive and the Ethanol content. It's old tech, it's never going to be great.

ghostrider

Anybody know of any ethanol treatment that will actually counteract the e-10 crap? I haven't seen any ethanol free fuel around here in a while!

And for the record I run 93 in mine since I have higher compression and am tuned to run on 93.

02SuperLariat

I use 87 octane since I know I am doing nothing but wasting my money using anything higher. Octane itself has nothing to do with performance. Octane just prevents pinging and if the ECU is programed for only 87, it won't do anything if you put anything higher.

The only time higher octane makes more power is say in a 2011+ Mustang GT. The ECU is designed to run on a minimum of 87 by reducing timing, but when it senses more octane and knows it won't ping with more timing, it increases the timing and you get more power. Unfortunately, our trucks don't come with that technology.

And I can smoke one tire for a block...in the snow or rain...

greenheadkiller98

The eth free is about 10 cents higher but all octanes at those particular stations are eth free. The 10% across the street is always cheaper but Id imagine eth free is better for my truck being assembled in 1997 lol. Works MIRACLES in small engines, dirt bikes, etc!!

spareparts

I have always run lawn mower fluid in my trucks except for the diesel I owned of course. My dad always ran 94 octane in his explorer till the mechanic told him to stop it cause it apparently was too rich for the 4.0 L and had been causing problems. So in my experience 87 works fine.

Bryan Ex

I'm mostly a reader on these forums but this quote requires a reply. I used to run a fleet of gas powered delivery vans. Most were Chev 305 and 350 but some Fords and Dodge in the mix. I did an experiment to find out if the more expensive gas saved money in the long run. I ran each van for 5000 kilometers on three different grades of gas using the same driver on a dedicated route and recorded all costs and mileage. The result was that the premium grades did produce better mileage BUT not enough to offset the cost different. In other words, I had to buy more regular gas to keep up but it cost less in total than the premium. I will say these were delivery vans and a few trucks and not high performance muscle cars so performance issues didn't play a part. Small engines on the other hand get nothing but high test at my farm to keep them running cooler.

- Bryan Ex

Jacob.P93

Do you know what octane means? I've ran from 85.5/87/91/93 87 has the best gas mileage/performance. 2 stroke oil will help you on mpgs more than running unreccomended fuel.

Hunttman01

We have the following in my small town in Iowa
87- unleaded
91- super unleaded
Diesel