Hicksbarry94

Ok I have a good bit of friends that work on cars/trucks. The thing I am wondering is it true or false to run high octane like premium gas in your car/truck every once in a while. I was told the high octane helps clean the fuel system. I have done it a few times with my f150 and have not seen any problems doing it. I have mostly done it right after a tune up and fluid change.

ScrewThat

False. All gasoline has detergents meant to aid in keeping the fuel system clean. It differs from refinery to refinery so one brand might "clean" better than others. But no. Premium is not meant to clean better nor does it clean better than regular.

And you won't notice any difference/problems running it in a stock motor except a lighter pocketbook.

Fordfan2006

I tried it. Ran smoother then when it got below half a tank it started getting pissy and taking longer to start.. So that's my experience. Got the same mileage too. Stick to regular 87 get quality fuel if you want to spend more on gas find a ethanol free station ( your truck will love it because well.. Ethanol sucks and I think that they didn't have it in gas when the trucks were built )

firegod33

Different vehicles will respond differently. My Jeep run smoother and gains about 2 mpg, running premium vs. reg. I haven't tried it in my F150. If you've tried it and not noticed a difference, stick with the 87.

the01kingranch

Won't make a noticeable difference without a programmer.

Purple Oil

This is just flat out not true. There is only one difference between the different grades of gasoline and that is their resistance to premature detonation which is denoted by the different grades they are organized into. If your vehicle was designed to run 87, then putting anything higher than 87 in it will not improve its performance/cleanliness/anything in any sense of the word. If your vehicle states "minimum 89" or "minimum 91 octane" on the fuel door, then running lower octane fuels increases the risk that you will damage your engine as you rev things up. That's it.

There is one, and only one exception to all of this. Depending upon where you live, the higher octane rated gasoline fuels may likely be ethanol free. Ethanol has a lower btu rating than pure gasoline and therefor, if you switch from an 87 rated fuel with ethanol to an 89 or 91 pure gasoline, then you very likely will see an increase in your fuel mileage around the neighborhood of 10%. However, that's due to the absence of ethanol and not the higher octane rated gasoline.

Jbrew

False. I have done it couple times in the past out of curiosity. I only noticed an exhaust note change. Slight but noticeable.

Fordfan2006

same here. My idle smoothed out a tad also then it started to start hard and take longer to start filled up with 87 and it's back to normal.

Jbrew

Mine didn't do none of that, it ran normal. It sounded different. Iduno, more throaty under normal acceleration I guess. Sounded a little better. It was cool man.

Fordfan2006

well I believe mine has oil leaking into the plug wells from the valve covers so that's why it idles rough.