2003 Ford F150, XL Supercab, sport edition, v6, 4.2L.

I usually fill up with 87 octane. Tonight, because gas prices have come down some, I put in 89 octane. I have HEARD that I should not use 93 octane because it will burn hotter.

What are the advantages and drawbacks to each of the levels of octane? What about more power? mileage/gallon, etc.?

Thanks.
Neil

 

It's true that higher octain fuel burns hotter, but premium you get from the gas station doesn't burn hot enough to be dangerous to the engine. Just don't try racing fuel

Technically speaking, premium gasoline will not increase the performance of a stock engine. You're also not likely to see any increase in your MPG. That being said, some folks say they can tell a difference in the way the engine runs when they use the high octain fuel. Most say they don't see a difference.

Personnaly, I run premium when I can, because I do notice difference in the way the engine runs. No performance increase or anything like that, it just seams to run better.

So basicly, it comes down to how your paticular engine acts and personal preference.

 

My personal experience with running a higher octane didnt amount to any noticeable difference in the either the way the engine ran or power/mpg improvements. I got the same mileage with both octanes (though shell gasoline gave me a slight mpg improvement). The thought of putting a chip in has always been in the back on my mind, but at the price gas is nowadays that thought sits on the back burner.

back to the question, everyone one has different results try running 89 on the next 3 or 4 tanks to see if theres any difference. If you like it stick with it and if you dont theres no harm running 87.

 

I thought I remember reading in the ford owners manuel NOT to run premium. Am I wrong?

 

It probably says it's not required, but I doubt it says don't do it.