Jason8691

Always 89, it pings on 87, and either Shell or Chevron.

cjkoz1975

I have a flex fuel 5.4, and I run 93 in it. I have been told by a ford mechanic that this is a good thing for keeping the motor in good shape. I also run a bottle of fuel injector cleaner through approx. every other oil change. I noticed with the 93 that I get a noticeable amount more miles per tank, and the truck runs great. As far as the extra cost, the extra miles I get negate the cost. I don't come out ahead, but I don't lose any money either. I think It's better though.

AzNative

Then you get to states like Wyoming and Utah. I live in Wyo, and the minimum octane available is 85. They don't charge any less for it though. I've only lived up here for 2 yrs, lived the other 32 in Arizona where everything was 87.

It is said you can get away with it because we are at a higher elevation. I don't know. I run it and have no problems...