Interesting. Valero, currently the #1 gasoline refiner in the USA was not mentioned at all. Anyway, it looks like the Tesoro gas I have been buying lately has only the bare minimum of additives. I can get Mobil or ARCO (BP) for only two cents more a gallon. The "top tier" brands are more expensive, a lot more than the one cent it costs for the extra detergents.
Personally, I like the idea that some providers like Exxon/Mobil and Ford don't join this "Top Tier" consortium. Exxon shouldn't have the auto makers dictating what additives go into the gasoline. There will be too many auto manufacturers wanting different additives. Supposedly to work the most effectively in their automobile. You don't tell the phone company to change their wiring or system to work on a particular fax machine or standard. You make the fax, modem, pc, etc... manufacturers build their equipment to be compatible with medium on which it rides on. Same here; The EPA dictates a certain minimum standard for fuel to assist in improving emissions, less varnish, less total gunk in the engine. Now that the fuel is at the standard, it is up to the auto manufacturer to build a vehicle that runs efficiently on that fuel. It's a lot more difficult to design a gasoline to work on 50 make/models of vehicles, than it is to have the auto manufacturers build their vehicles to work with 1 gas standard. If the gasonline providers want to go ABOVE the standard, that's their choice.
I think that is why I like Exxon/Mobil. From an oil company comparison, I believe that they do have a set of standards that are higher than the EPA. I also LOVE the fact that they don't include ethanol in their gas; at least in my state. Even the link above commented by a person who use to work for the EPA who said he doesn't care about "Brand" gasoline, but he WON'T get gasoline that has ethanol in it. Kudo's Exxon/Mobile. Also, it seems that Ford is building their vehicles to work on the fuel source available, instead of trying to force the fuel providers to change the additives in the fuel to work on their vehicle. Kudo's Ford.
Where I live, Exxon/Mobile fuel costs about the same as the Mini-Mart, Walmart, or any other station. Most have E10 oxygenated ethanol. I will stick with Exxon/Mobile without question. Later... Mike....
Shell gas in my area cleans your fuel system real well. Shell has started using E10 in my area. It cleaned my fuel system too well. That little bit of ethanol cleaned enough rust off my filler tube to expose pinholes. Now if I get to 1/4 tank my truck starts starving for fuel. I will not touch shell until I fix my fuel tank. After that I will go to using it again.