I wonder if y'all could answer something for me because I've never fully understood the Octane rating deal. I had a truck(98Chebby 5.7) that would ping badly at times. I only used 87 octane in it. Where I work, I've had two different trucks that ping really bad.....one was a 2000 chebby 3/4ton 5.7 and the current one a 1997 Ford F-350 5.8. I haven't tried it with the Ford, but when I would switch from 87 to 92 octane on the chebby, it never pinged, but did it quite often on 87. These are just fleet trucks, so I can't imagine they have been tuned or anything. I have been using a higher octane in my personal truck...2005 F-150 5.4L because I've had other trucks that pinged on 87. Now I'm a bit confused on which is right lol.

 

I would venture to say that the Chevy possibly had a little more timing in it...
Or maybe they have a little more aggressive set up from the factory. I wouldn't know as I have never owned one ( 5.7 that is)

 

In my experience from driving fleet trucks (1999 Ford E250 and 1993 Aerostar), when they get lots of miles on them they do start pinging a little bit. As I recall, when I took them in for normal services, the mechs would start suggesting tune ups on them when the mileage got high (about 60k-80k). Sure, when you put higher octane gas in it, the pinging would go away because you're using gas with a little less explosive power (that's right! less power!). I tend to think that after a whole lot of crap builds up in your fuel system as the miles build up, it's going to tend to ping. You could probably improve things in your fleet trucks by having your injectors cleaned, as well as the intake. Crap in those areas could really affect how the fuel mixture combusts in your engine. Ask the guys in this forum about Seafoam. It is quite capable of addressing your particular needs. These guys could probably add a little more info than I can. Also in your '05 F-150, use 87 octane as per your owners guide. Don't give the oil companies any more money than is necessary. They are doing nothing but laughing all the way to the bank.

 

I guess I could expand upon my use of the word "crap". In general, concerning engines, it's carbon deposits. I didn't mean to make you think someone crapped in your truck. Sorry.

 

Speaking of (crap) deposits, I have actully seen engines that have so much carbon build up in the chambers that it has actually increased the compression and thus caused the engine to ping.. unbelieveable but true... Back in the old days it was a common thing to actually pour a little water into the carb. while holding it wide open to break the carbon and lead build up out of the heads... You didn't want to be standing behind the exhaust pipe opening when this was done because that **** hurt when it came loose and was exhausted ......

 

On my old bronco i did that but with ATF.

 

I am just starting to understand octane used with new engines and I as far as I am concerned running premium in the new ones offers no advantage.

Now in the old days, my dad had a brand new 1970 Ford Wagon with a 390 and it always pinged a little, right from new. The motor was apparently famous for it. The dealer could never fix and my dad would run premium and there would be no pinging. I don't know if it had any more power or not but I can confirm the pinging/no pinging with the use of reg/prem.

In my snowmobiles, prior to digital ignitions, detonation was a major problem. With too much detonation (pre-ignition) the piston would shake too violently and the bottom ring would "clip" the large exhaust port on the way down and break the ringland between the two rings and disaster would soon occur. With the use of premium it would lessen the chance of pre-ignition therefore extending the life of your pistons. So in this case although it does not provide more power, premium fuel can save your engine.

I run premium with my new Superchips 1745 Tuner and it is great! I Won't go back. Wthout the tuner I would not even consider premium.

 

i find it amazzzing what a thread on octane rating will stur up


puzzzzleing indeed carry on

...zap!

 

thanks for all your help guys. I really enjoy and appreciate all the helpful posts without all the sarcasm.

 

Hey tmilam, I didn't notice until now you're a fellow Arkie. There are a few folks in this forum down around your neck of the woods. Welcome to the forum, and keep coming back if you have any questions about your F-150. There are plenty of very knowledgeable guys about a lot of things here. I don't consider myself an expert, and there are some questions that I don't even touch because it may be out of my league. But I've learned a lot about my F-150, and I'm still learning. See you around. Keep raisin' hell in Conway.

 

I wonder how many of you jokers got your answers from Google

Some of you are "experts" non-the-less.

 

Question for the guy's that get Gasohol up north. How much does your mpg suffer when you get run this?

I'm just wondering because I keep hearing peole say premium gas has less energy, which it does, but it's so small you shouldn't notice it... 87 gasoline to 87 Gasohol would be the biggest energy difference in fuel people should really see so I'm just wondering.

 

So you all are telling me that the bigger number isn't the better gas? I thought bigger was better.

Can I put moth ***** in the gas tank to get more octane?

 

When I had my 02 explorer someone put premium in it and the check engine light came on, dealer said no premium after a couple tanks of 87 it went off, unless there is a sticker on the gas cap saying premium only us 87, I tow with my 04 5.4 has plenty of power on 87 and you will not see are feel a difference in gas milage or performance my 04 get around 20 mpg highway.
I use 92 in my snowmobile, on the dash plate it says 92 or better.

If you want to play the octane game go for it..

 

Thanks for the info guys....I guess I'll just use the 87 octane in my truck and save the extra money for more mods.