Better gas mileage with different octane?

Hey Everyone,
New to TacomaWorld. Traded in my Wrangler and bought a 2017 OR AC late November and could not be happier. A buddy of mine referred me to the site and it is AWESOME! Question for you all...have been filling up with 88 octane first 3 fill-ups was averaging 18 - 18.5 mpg. Recently filled up at a new station with 87 octane and my mpg went up a whole gallon to 19.5. This is mainly city driving on fairly flat roads with the occasional freeway run. The truck only has 1100 miles on it. I drive it every day but, really only back and forth to work and around town(camping/flyfishing season has yet to begin). Wondering if the octane made any difference or if the truck is just "breaking in". Thanks, and glad I was turned on to the forum. Cheers.

 

My mileage varies more based on the amount of ethanol.

 

87 vs 91 in Colorado I see no difference in mpg.

 

I seem to get a little bit better mileage with premium

 

Here we go again.

Toyota says to use 87. Just use 87.

Winter gas blends suck.

 

The real question is: Is premium Ethanol free where you are? That might make a difference.

 

Both premium and regular ethanol free

 

It went up a whole gallon? You surely meant it went up a whole mile per gallon? One mile per gallon is basically zero change IMO. You simply cannot and will not replicate the exact same driving conditions every day. You need a bigger/longer experiment.

 

You're a lucky son of a bitch then.

 

I use ethanol free here in Colorado. It’s 87 octane I believe. Runs great on good ol gas.

 

Yes, I meant a whole mile per gallon. I agree, I will continue to observe and see what happens. Thanks for the responses and being kind to the noob.

 

over in the MT's new truck mileage often starts with under 15mpg and goes up to the higher teens or even 20's within a few thousand miles. on the same gas.

 

I get the same 87 or 91 so I stick with 87 now

 

Regular gas done waste your money

 

Octane rating makes absolutely no difference in mpg. Higher octane is all about resistance to engine knock during fuel detonation.

With that said...
If you consistently run a higher octane fuel, your timing will adjust accordingly over a period of time. Because of the change, you will have a bit more horsepower at wot. Probably not enough to notice but it will be a bit more.

As far as efficiency though? That is a nope.
You had a coincidence happen. Nothing more.

 

Answer I was looking for. Thanks.

 

The only thing that changes your mileage will be the available energy in the fuel. What I mean by that is basically ethanol content in traditional pump gas. Some engines take advantage of the additional fuel stability of premium and change engine parameters, most don't. The Tacoma's engine doesn't

 

I use ethanol free only. Get an extra 1-2mpg vs when I used to use the normal blend up to 10%. Costs about $3.00/gallon these days. Race trac is 87, wawa is 89, marathon is 90.

 

I tried two tanks of 92 and lost some MPGs. Back on 87 and feeling good.

 

I run 93 in my truck for this reason. When I first got my truck 12/16, I used 93 as I was babying my truck, switched after a while to 87 and ran that for 5 months or so. I then switched back for the last 5 months to 93 and while I don't notice any more power or better MPG (I have gotten my best and worst tank AVG on 93, consecutive tanks too.), I do notice that my truck does not do the low RPM chugging on 93. I buy 93 because my truck just hums along better with it.