Rt1Rebel

austijc is correct. Unless you are buying your gasoline from a broken down convienience store with pumps that have rotating meters, you are basically buying the same product. Turnover is important, and octane is important if your car demands it, but other than that...

BTW, I work for a catalyst concern and we make the products used to refine the lowest crudes into gasolines and jet fuels. We make catalysts for all the major brands, although my specific product line involves Chevron.

Treatz

so is the general consensus it's all marketing and all the gas is the same?

Rt1Rebel

I wouldn't say EXACTLY the same, but equivalent. Even using the same brand all the time, you are likely to get a batch with different additives. Additives that are designed to do the same thing as others. Distribution is the difference. It's actually a good thing to run a different additive gasoline through your car once in a while because most of the additives are designed to clean and maintain fuel systems, and some mixtures work in different ways. But like I said, you are likely to do that unwittingly even filling up at the same station every time.

Orion_240

Some seem to be missing the picture!
While the oil may seem to all be the same there are BIG differences between the Saudi/Middle East Crap and real American crude! I think it's referred to as Light Texas Sweet? Or something. It's the best and the middle east stuff needs much more refining to be used as gas.
Plus, there are more than one way to refine the oil! What's going to USA stations could have been made diffeently from what's going to 76 or Mobil. Plus there can be differences betreen each delivery of gasoline to the stations, especially if they have stolen some gas and poured water in!

Rt1Rebel

That's irrelevant, Orion. Canada has sand oil and Venezuela has some crappy crude. Saudia Aradia has the cleanest, thinest oil in need of the least refining. It is all pretreated in a Hydroprocessing step if it's of particularly bad form and then processed and cracked just the same in columns with Fluid Cracking Catalyst. It all ends up the same product.

And the urban legend about watered gasoline just doesn't mix. Literally. Gasoline floats on water. Not to say that old or poor gasoline does not contain entrained traces of water, but the idea of actually cutting gasoline with water is just ludicrous. If you don't believe me, try mixing motor oil with water. The density of motor oil is closer to the density of water than the density of gasoline to water. The smaller molecules of gasoline do however enable some water to be entrained. Under constant agitation, I suppose that this could be a possibility.