Better Gas Mileage using Shell Gas vs Chevron

[Luv2Box]

When I fill the tank with Chevron my OBC reads 340 miles for the tank and when I fill with Shell it reads 299 miles for the tank. The reading is taken right after the fill sitting still. Any thoughts on what causes this?

[cas951]

Originally Posted by Luv2Box

When I fill the tank with Chevron my OBC reads 340 miles for the tank and when I fill with Shell it reads 299 miles for the tank. The reading is taken right after the fill sitting still. Any thoughts on what causes this?

Did you check to make sure conditions are the same? Your current average mpg when filling the tank.

[Luv2Box]

Originally Posted by cas951

Did you check to make sure conditions are the same? Your current average mpg when filling the tank.

Yes conditions appear to be the same the fuel gauge needle is right on the full mark. For some reason the OBC is indicating I will get more miles on a tank of Chevron than a tank of Shell.

[BYprodriver]

While I worked at both Shelby & Saleen during the EPA emissions certification process for new manufactured vehicles, 2 different emissions certification engineers were adamant about using nothing but Chevron Supreme in test cars. That's all I use & it's usually the most expensive option. I just paid $4.12 per gal at my local station.

[Porsche9]

Originally Posted by BYprodriver

I just paid $4.12 per gal at my local station.

$4.12 per gallon! What's in that gas that it's $4.12 a gallon? The Chevron by my house is $2.83 for super.

[leftfield6]

To the original poster's question, though, one tankful is not near enough of a sample size to determine any changes in fuel economy. To accurately gauge fuel economy, you need a large sample size.

For the argument about one brand of gas is better than another, I give you this.