In the current world of $4 a gallon gasoline, everyone is looking for an edge. Whether it’s additives that don’t really work or little gadgets that don’t really work , we’re looking for anything that will squeeze out a couple more MPG from the car we already have.
The next logical step is to ask whether the gas at various gas station companies makes a difference. For the longest time, I believed that the gas from Exxon was better than the gas from Costco. I did empirical studies where I saved my gas pump receipts and calculated my average MPG and the Exxon gas did give me 2-3 MPG extra. However, after further research, I believe that my driving behavior and routes had a greater effect on fuel efficiency than the label on the pump.
The gas from one company is essentially identical to the gas from another.
Government law requires that all gasoline certain detergents that help prevent fuel injectors from clogging. This means that all the fancy brand name gas stations and their fancy “additives” are all required and that all gas contains them. Some say that the detergents from brand name companies go above and beyond but my perspective is that you only want the minimum standard, which is required of all gasoline. Why do you want more detergent than you really need? I don’t want more detergent in my gasoline, I want as little as possible because that gives me more gasoline! (I’m only kidding, the added volume in detergent is tiny)
Many gas brands share pipelines. According to a Smart Money article on what Gas Stations Won’t Tell You , Chevron gas stations might sell gas refined by another company like Shell or Exxon Mobil, with the difference between their gas being a quart of detergent added to an 8,000 gallon tanker truck! After a little digging, I found these maps of pipelines  in the US and there aren’t that many pipelines. There are certainly as many pipelines as there are gas brands, so the fact that they mix and match isn’t that surprising.
If there was a difference, we’d know about it by now. The power of the free markets is very strong, if a particular brand of gasoline was definitely superior, we’d know. We’d know because it would be more expensive because the higher performance would justify the higher cost. Since there isn’t a brand that exists with significantly superior performance at a higher price, it’s clear that they’re all pretty much the same (and these brands have been around for decades).
If you really want to make a difference, you can save more money by buying the cheaper gas and then adding a fuel injector cleaner with every oil change. I’ve used many a fuel injector cleaners, which you can find in any auto parts store, but can’t really say I can tell. The mechanic friends of mine say that while it can’t hurt, don’t bother getting expensive cleaner, just get the cheap stuff.
Oh, another tip, don’t buy higher octane than you need , it’s a waste of money.
(Photo: ella_marie )