Which Gas Am I Getting?

[honestone33]

Modern engines can detect knocking(detonation).
If your car says to use premium, then use premium. I won't argue that-both in theory and from my experience in the real world it gives the best gas mileage and performance. A tank of regular mixed in with a diet of premium won't hurt a darn thing, though, in the short term or the long term.

That's what I do, for our Mercedes. Will NEVER mess with mixing different grades of gas. Cannot see the reason why, and the savings will be, at best, minimal. For example, say a tank takes 12 gallons when empty. Mixing 6 gallons of Regular Unleaded and 6 gallons of Premium Unleaded might be "OK", but the savings versus just using Premium would be $1.20 (typically 20 cents a gallon difference between the 2). Wow, what a savings!

Also, there is the hassle of using two pumps. Don't need that!

Until a station messes with you and puts premium in the center or on the left, which I've seen more times than I care to count(although I'd guess center is the most common "different" placement).

Have NEVER seen that. But I also have eyes, and can read where it says "Premium Unleaded". And am never missed it!

And yes, if you ever travel(I drive about 2.5K miles a month on average) it's easy enough to find yourself at an unfamiliar gas station where they are in different places even if you normally go to the same place around home.

I don't drive nowhere that much, but have driven in numerous other states, and STILL have not seen such an anomaly.