is this safe?

[Nigel215]

just a quick question..ive been running 89 octane gas for about a year now, but the price of gas is really killing me. is it safe for me to just go back to 87 again? I dont have any custom tune or anything, but i was just curious if this would cause a knock or something, or just not be good for the engin? thanks

[Seabornman]

I've never run anything but 87, and it does just fine. I have an '01 4x4 with 4.8 engine. I agree, there is a big price jump to 89 octane.

[BowtieX3]

Your Owner's Manual has factory suggested fuel recommendations. It will say what you should run...however, keep this in mind...the higher the octane, the cleaner the fuel, meaning the more complete burn you'll acheive, meaning the better mpg you'll get. You'll also have less carbon running through your engine, less potential for future problems. Uncle works for Exxon...take it for what it's worth.
I know prices at the pump are horrendous (I have to run 93...6.0 HO). If you do run 87...twice a year I'd run a cleaner like the Chevron concentrate through a tank...my two cents worth!

[jeverett]

I've run 93 since the day I bought my truck almost 4 years ago. I'm swapping back to 87 next week when my new tune is here. I've got to, the 93 here is almost 2.70/gal

[jers99z]

i would say if you dont have a chip or tune done running 87 should be just fine, ive been thinking about taking my chip out just to run 87, gas prices are ridiculous in hawaii and driving over the mountains aint exactly fuel efficient

[White Lightening]

Originally Posted by jeverett

I've run 93 since the day I bought my truck almost 4 years ago. I'm swapping back to 87 next week when my new tune is here. I've got to, the 93 here is almost 2.70/gal

I did a calculation as follows:
If a truck owner drives 15,000 miles per year averaging only 18 miles per gallon using 92 octane and the difference in gas price for 92/93 to $2.70 per gallon versus $2.50 for 87 octane fuel. Lets also use the fact that the average (MPG) would go from 18 (with premium) to 17 (using regular). The actual net difference in cost ====== $45.00 a year.

As a result - it seems it would not pay to switch to lower octane. In my area - the difference in price from premium to regular is only 12 cents a gallon where I get gas. However I had used 20 cents in the calculation - to even try harder to favor regular. Even under those conditions - $45.00 just isn't worth the difference in my opinion - I'll stick with premium till it cost justifies a switch.

[Nigel215]

Originally Posted by BowtieX3

Your Owner's Manual has factory suggested fuel recommendations. It will say what you should run...however, keep this in mind...the higher the octane, the cleaner the fuel, meaning the more complete burn you'll acheive, meaning the better mpg you'll get. You'll also have less carbon running through your engine, less potential for future problems. Uncle works for Exxon...take it for what it's worth.
I know prices at the pump are horrendous (I have to run 93...6.0 HO). If you do run 87...twice a year I'd run a cleaner like the Chevron concentrate through a tank...my two cents worth!

Yea, that is one of the reason i started running 89 in the first place, for everything to run a little cleaner.

[sportin83]

i try to run 89 most of the time, but i get 87 once in a while. sometimes if i have a few extra bucks i though in 92 or 93. the way i look at it is if you run 87 then once and a while i have been told you need to run a fuel cleaner throught the system, but that is like 4 buck s a bottle so what are you saving by going cheaper on gas?? my 2 cents

[twomorestrokes]

87 octane is fine with your stock truck. That's all I use in my 6.0. and I rag it hard. It is a waste of money to use higher octane than you need to in a stock vehicle. Although it won't hurt anything, you are not doing your engine any special favors by spending more $$ on slower burning fuel. Higher octane is only needed to prevent preignition when the compression or timing has been altered, or if it is a special factory performance package.

As far as cleaner burning goes, the big oil compaies have gotten you believing that. If anything, using higher octane than you need to has the possibility of being less clean. All higher octane does for you is make the mixture harder to ignite in your cylinders. If you are having detonation problems then higher octane is for you. If it runs good on 87, then it is actually burning faster and cleaner with lower octane.

[Ape0r]

89/93 are not any cleaner at all than 87, except with brands such as Shell that offer additional advertised cleaning agents. The octane number relates to resistence to combustion, you will achieve a more complete burn with the CORRECT octane rating. If you have a 93 tune, use 93. If you have no tune, use 87.

[White Lightening]

Originally Posted by Ape0r

89/93 are not any cleaner at all than 87, except with brands such as Shell that offer additional advertised cleaning agents. The octane number relates to resistence to combustion, you will achieve a more complete burn with the CORRECT octane rating. If you have a 93 tune, use 93. If you have no tune, use 87.

Actually Ape0r, thats not quite correct. Many GM products benefit from using premium gas. Octane numbers - as you mentioned - do relate to resistance to combustion. 93 has more resistance than does 87. But its compression ratios when used in conjunction with octane numbers that give you the right choices. I have a 10:1 ratio compression - and using premium is needed. The result of using premium with higher compression levels - will give better mileage and better performance. Similarly - using premium gas with a low compression engine - gives you unburned hydro carbons, poorer mileage, and a loss of power. Most bigger block V8's improve with premium. Most V6 engines work better with 87 octane (because they don't have high compression).

[NoRiceHere01]

thank u for knowing wut ur talking about haha. im tired of explaining to people wut octane ratings mean. these things run fine on 87 and ur engines not gonna notice the switch. running a certain fuel in ur engine does not condition it one way or another. my 76 ran on 87 like it was supposed to until i advanced the timing to a suitable level and then put an advance curve kit in the distributor. i thought i killed something cuz of the noise it made until i took my dad for a ride to show him and he was like "u need better gas idiot u know wut u just did to the timing?" unless u got a tune or raised the compression ur better off with 87. if not for the price, as white lightning pointed out, then for emissions. if u use a fuel that does not burn completely then ur actually increasing bad emissions. not that i care. emissions regs suck. now that i think about it, if i read the advice i just gave, i would be no closer to a desicion then before i read it. please ignore me, its been a long day.

[Slowprocess]

Running 28 degrees of timing and nitrous.....I think I'll stick with 93.

[broughy84]

Wanna here something sad.......

At BP here gas is $2.22 for 87, 2.32 for 89, and 2.42 for 93.

At Casey's its $2.27 for 87, and $2.20 for 90, yes that is right, it is not a type, premium is cheaper. The Reason being, they have a larger tank tank BP (as they are across the highway) and they can buy in huge quantity... Low price = high demand

At D&B 87 is 2.52 and 89 is 2.85 this station is only 10 blocks from the others. What a difference!

[jeverett]

I'm broke, im going back to 87