I've been pumping my 04 Z with Chevron 91 gasoline for a while on my past G35 and now on my Z as well. Does brand X's 91 octane gasoline vs. brand Y's 91 octane gasoline make any difference on the motor? I've seen a lot of commercials especially by Chevron on how happy their gas makes their car feel, does it really make any difference on the longevity of the car? Chevron also happens to be the most expensive per gallon in my area(CA), am I paying more for higher quality gas, or just Chevron's marketing campaigns?

 

i usually put in chevron/exxon only in my car. Maybe its my head but it feels a lot smoother. Also, i read in teh newspaper that the supermarket's gas (IE:costco/bjs warehouse/sams club/) stations uses cheaper, not as clean burning gas.

 

I swear that I get the smoothest idle and best MPG on Chevron Supreme. I told all of my friends this 10 years ago, and they cried BS!...










...and sheepishly admitted later that they had the same results.

PZ

 

only chevron with techron for my baby!

 

yea this website should explain and few things, then click the retailers for the list of gas stations, etc....

http://www.toptiergas.com/index.html

 

^^^
I use BP and Shell, and BP isn't top-tier

 

Sunoco Ultra 94 ftw. For awhile around here, Hess was using watered down gas, i don't know if it was a rumor or true though.

 

We don't have any Chevron/Exxon in Colorado that I've seen. So Shell is about the best around here. I also swear I can tell the difference between it and the lower-quality gas at Citgo or Albertsons.
Will

 

Its been proven that all these stations use each others gas if they run out from there supplier...truth is you never really know what is going in your car.

 

What proof? Link or anything to the story or article?
Of course most small stations have to purchase their gas from some blender or refinery, and can switch their supplier. But stations like Chevron or Shell are going to use their own gas, since they are the supplier. Who really knows where Albertsons or Sam's Club buys from, but I find it very hard to believe that a supplier station like Shell is suddenly going to fill their tanks with a different supplier's fuel. Especially since the Shell stations around here all closed down for a few days when they lost supply from their normal refinery's depot if they could just have had their tanks filled with some other supplier's fuel, like bought and trucked in some from Sinclair or BP.
Will

 

Here is the link to the article in usa today http://www.usatoday.com/money/indust...gas-usat_N.htm

For those that don't want to read the entire article this is what I was referring to:

Further clouding the question of what is good gas, brands often sell one another's fuels.

"Gasoline is fungible. Marathon can market Shell or Mobil gas, for example," says Darlington, the consultant and fuels expert. Marathon stations "normally get it from a Marathon refinery, but if something happens to a Marathon refinery and there's a pipeline where they can get Mobil and market it as Marathon, that's the way it is," he says.

The substitute fuel might contain a different additive package, but it's supposed to be at least as effective as what the station normally sells.

If you read the entire thing they basically say gas is gas

 

Gas is not gas. Racetrack gas is chit.

 

Maybe that is true...the point I was trying to make is that it is possible that racetrack gas ends up at your favorite gas station...whatever that may be. It's also possible that if you fill up at racetrack your getting your favorite gas. You really never know!

 

Well from my understanding places like Racetrack buy up all the surplus gas from everybody and it's a mix of a whole bunch of different gas. That is why they are able to sell at a discount. So I guess in a sense you are 100% correct

 

sunoco FTW

 

That's an interesting article, good to know. Thanks!
Will

 

When you follow the tanker trucks back to the terminals ypu will see th truth.

The branding of gasoline comes from the additive package that may or may not be added to fungible [generic] gasoline as the tanker is being filled.

The octane is set at refinery and defined by the pipeline standards.

 

seems like my question here cannot be answered clearly unless you know someone important in the oil industry.

 

The basic answer to your original question is "no". All 91 octane gas is made to the same specifications. The only difference is in the additives, most of which probably have no verifyable claims. (i.e. keeps your injectors cleaner). Face it, the only thing you see in gas advertisements is those kind of claims. There's not much you can advertise about "gas" because the basic product is the same anywhere you go.

When a gas refiner put 100K bbl into a pipeline at one end, the purchaser at the other end doesn't necessarily take out the same 100K bbl of gas. He buys gas based on a standard specification, he doesn't know whether refiner "A" or "B" actually supplied all or part of the stream.

So unless you believe the marketing hype about the additives, there no reason to buy one vs. another gas other than personal preference.

 

+1. This has been a running question for decades and the evidence shows that the stuff is all the same with a lot of claims made to make individual brands seem unique. The only gas you have to be careful of is the one that promises to put a tiger in your tank. You need a special filter to clean out all that fur.