I was discussing current gasoline prices with an associate of mine, and he comes out to state that he only purchases unleaded fuel from Mobil or Exxon stations. I found this perplexing to say the least . Are there any advantages or disadvantages of purchasing one distributor's gas versus another's? Is there a difference between fuel quality obtained at your Local Shop-Qwik vs. a national distributor?

Many thanks to all for answering my questions.

 

all fuel in the US comes from about 7 different refinerys. (well, make that 6 now.......) While there are some variations in the mix, gasoline if HIGHLY regulated by the govt. for content, additives, etc. I would guess that you could get gasoline samples from several different gas stations, and find very little difference in the blends....... (all being the same octane rating.)

 

From the AP report on the explosion: "About 433,000 barrels of crude oil are processed a day at the plant, producing 3 percent of the U.S. supply." That's a lot less than 1/7th.

There may be 7 different companies refining crude, although I don't know that for sure.

For the daily drivers, I look for the least expensive. There's an independant about a mile from my house where I do most of my fueling, I've never noticed a difference when I happened to get gas somewhere else (and I keep records on all 5 vehicles in my "fleet"). For the "race car", though, I always get gas at Phillips 66 or Conoco, just for the sake of consistency - and it probably doesn't really make much difference.

One of the biggest differences, here at least, is what they use for the "oxyginated additive" - MTBE, or ethanol. MTBE is nasty stuff.

(FWIW, Exxon Mobil doesn't operate here.)

 

Not sure if it's the same system over in the USA but here, almost all petrol comes from the same source. However different companies have their own additives that get mixed in with the fuel when they fill up at the refinery. These additives are probably not going to be noticed in SBC engines but probably have more impact in fancy modern engines.

The only difference that you may notice between different "brands" is how much dirt etc is in their tanks.

Si.