Cheap gas vs expensive gas

I've always pumped "cheap AMPM" gas in my past tacoma...
And was told that cheap gas will more than likely impact mpg.

For my 3rd gen, i decided to do an experiment on pumping chevron and shell vs the cheapest gas station I can find around town.
Everytime when I fill up at a cheap gas station, on a average tank it will show an averange mpg of 16-18. but when I pump at Chevorn or Shell it will average around 14-15 mpg.

Been pumping cheap gas in the past and i never seem to have any problem as mechanical failure. Neither could tell the difference in performance.

What's the deal here?

 

I do not want to be critical, but that seems very odd. Are you sure you are controlling all of the variables correctly?

 

I have tried that also in my previous vehicles the only difference I seen was I got better milage with Chevron. As for performance I never seen any issues. I always tried this during winter time. Summer in the mornings I'd have windows open and during the day air conditioning going when it got hot. I'm in Modesto so gets very hot as you probably know. This way I would get more of an accurate reading.

 

So you have proved it yourself; your truck likes cheap gas. Stop looking a gift horse in the mouth.

 

Yes! I always reset my odometer trip every time at fill up and I can see that I have lost about 20-30 miles on a full tank. This is same route commute to work. This past two tank (using cheap gas) I can see that my mpg has improve...

I know some will disagree...

 

TW has no love. Was just looking for info...

 

I'm certainly not trying to disagree, it just seems baffling, doesn't it? I'm sure you've double-checked for octane. Interesting.


If you don't want to read a stupid but supposedly true story, stop now. This is how I remember something from Reader's Digest many years ago.

A lady took her car to the mechanic and told the mechanic that after she stopped for pistachio ice cream her car would not start. She said that she knew that this sounded very crazy, but it had been going on for a long time and she was sure that it was true. On the way home from work she would occasionally stop and get some ice cream. Most of the time she had no problem, but when she got pistachio the car would not restart. Somehow they finally put together that the flavors of ice cream she usually got were pre-packed, however the pistachio ice cream had to be hand packed and in the time it took to pack it the car developed a vapor lock.

 

Octane has nothing to do with potential energy in a gallon of gas. Neither does price. A gallon of gas is a gallon of gas. The only variable could be the amount of ethanol in the fuel. Higher percentage of ethanol equals less potential energy.

 

The gas from the Chevron station and the gas at the cheap store could have very well been delivered from the same tanker. It came down the same pipeline to the distribution center. The differences are additives and how much they charge. Places with high volume sales tend to have fresher gas. Mom and pop places may only have a tanker load delivered occasionally and it could be old or contaminated.

 

This exactly.

 

please see the following for a posting I submitted on a similar subject - Is gasoline brand consistency still a thing?

YES, there is a difference in gas brands, please visit www.toptiergas.com to view gasoline brands which must meet the high standards of TOP TIER Detergent gasoline. The additive "packet" is added to the fuel AFTER the tanker has been filled. Top Tier fuels are needed for TDI engines, non-Top Tier fuel will create additional carbon build up.

In regards to ethanol free gasoline, IF you prefer to utilize ethanaol free, you can find gas stations in your area at www.pure-gas.org ...

But, do utilize ethanol free fuel for your small engines (2-cycle and 4-cycle), small engines do not work well with ethanol and Sea Foam, Stabil, StarTron, etc. will only help a little ...

 

I wasnt referring to u as "disagree"

 

Additives do not change the energy content of a gallon of gas either. Nor will additives help/hurt efficiency for one or two tanks of gas.

 

Wait... cheap gas? Is there such a thing?

We have maybe 4 major chains in and around Wichita and a bunch of little independents here and there. It doesn't matter where you fill up... you will pay the same. It's like they're all in cahoots! If there are two competing stations on opposite sides of the street, and one says $2.09 and the other is $1.99, by noon BOTH will be selling $2.09 gas.

Sorry, I digress.

OP... you still haven't answered: it is the same octane, correct? Mid-grade here is 89 E10, while regular is 87 with no ethanol. The 89 burns much faster due to the ethanol but is usually close to the same price.

 

Nearly every major gas station is top tier now. Shell, Chevron, Exxon, Valero, etc. That means that all stations and all grades must meet a certain minimum detergent requirement.

Only time I'm ever preferential is when I can choose between a station that has E10 and one that has E0. Otherwise you're just splitting hairs..

 

Need more data. Do the same thing for 100 tanks of each and report back.

 

Here the least expensive gas is at Costco which is also Top Tier gas with 5 time the minimum level of detergents. So the best is also the least expensive.

 

The owner's manual says use Top Tier gas. Is something else cheaper in the long run?

 

Gas is very cheap in the continental US. In December I paid ~$3.60 a Gal in Maui, a few years ago we paid ~$11.00 a Gal in Italy (after converting for the Euro and liters). Count your blessings.