Hey all I seem to get better mpg when using shell 87 regular. My hand calculation an average shows a .5 mpg increase when using shell. combined driving at 30 miles per day.

 

well shell has all those "performance enhancing" additives. in general, we find exxon to have the least dieseling and most power for the price around here.

 

There's probably something to that. Since i started using this gas they sell at Walmart, my mileage has dropped off a bit.[&o]

 

Possible, but places like Wal-Mart, Speedway, in other words non-gas producing stations buy there gas from refinerys like SHell, BP, Sun, ect. And they usually sell the gas for less than than BP and Shell stations. Do your homework, ask the station where they get their gas and you will get the same fuel for a few cents less.

 

The gasoline blends change from day to day, all gasoline is pretty much the same thanks to Uncle Sams regulations. You can take any one brand of gasoline and in any one given day there blend can change many times. it all depends on what product is available at that time to add into the gasoline. It's never the same. If you by shell today it will be a little different on the next shipment. The best time to get gasoline is late at night or early morning ,never buy it in the middle of the day. You will get more for your dollars if you listen to what I said.

 

Why is there a difference relating to the time of day?

 

I think someone has been pulling your leg.

 

I think the brand of fuel doesn't matter much. When a I choose a station, first look at $/gal, there is usually a station that is slightly lower in the neighborhood, and second volume. I also try to use stations that pumps a lot of gas because their fuel doesn't sit around quite long enough in storage tanks for condensation to form.

 

I think where you buy may make more of a difference. I usually buy chevron here in Garland but I pass a Exonn in Wiley at 78 and 544 every day so I've bought a couple of tanks there. I think I get better milage with the Exonn. The reason I think that is is because the Wiley Exonn is in Collin county.

Some areas have to run a higher concentration of the oxygenation additive (reformulated gas)
than others and even higher concentrations in the winter months. That stuff causes you to burn more fuel. I don't know why but it does. Alot of rual cities and counties don't have to run as high a concentration.

 

I think it does matter... but it depends on how your motor is tuned... in my M3, I get the best performance using Union 76 gas, Chevron is ok, shell is probably ok but I never use it because of past experiences with it. Arco is out, and no-name stations are out unless I have no choice.