#1 Shell
#2 Mobil
#3 Cheveron

I'm with Chuck on this one. It's way more important to get your fuel from a station that clearly has to refill its premium fuel stores frequently.

I have been using Arco 91 octane in my '09 since new. I'll bet it's had less than a dozen tanks of gas from other stations through it. No problems encountered at all. I do add 8 oz of MMO to the tank about every 1000 miles, that seems to help with the sticky fuel level sensor, and I run a bottle of Techron through it before each oil change. Arco is top tier, use with confidence.

In my view,i think big Oil Companies should have more budget for R&D,so their fuel will be better..

I use Arco, Valero, or anything else that is Top Tier. No issues at 60k miles!

Ethanol Free 93 only

chevron or shell

Im in the same boat as the O.P. Before getting my Z I really went wherever they had the lowest price. Since getting the Z I read a little about Top Tier gasoline and decided to try and use only that. I have read some good things about Shell V Power Nitro but the closest one to me is 1/2 hour away. 93 octane always.

Hey fellas,

I work as a chemist for a Valero Refinery, my job is to certify the finished gasoline. We ran a bunch of different tests on the fuel. My primary test is to check the octane rating, whether we're selling 87, 89 or 91. From what I know working in the refinery is that it doesn't matter where the gasoline is coming from...whether Chevron made it, Shell, Arco or Valero. Our gasoline gets hauled to different gasoline stations not just Valero's. Furthermore, a lot of gasoline from different refineries get pooled in what we call Commuter Tanks off site. So you see t doesn't matter who made it but what does matter is the gasoline station you're getting it from. I am told that Chevron with Techron is the best additive you can put in your gas tank, followed by Shell's V-Power. I get a small discount at the Valero pump station here at work...but I still pump Chevron. Anyways, I just wanted to chime in. Thanks