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Gas and octane

I received this recently from a friend. He had watched Andy Rooney who noted that the pricing of the three grades of gasoline was disproportionate and the folks using Mid-grade fuel were getting ripped off. Since he drives a car requiring Mid-grade, he fills half his tank with Premium & half with Regular. He noted his price savings. My friend noticed recent the pricing at a station:

Regular (87 Octane) - $1.83

Mid-grade (89 Octane) - $1.98

Premium (93 Octane) - $2.08



So, if you get 18 gallons of gas and use 2/3 Regular plus 1/3 Premium (optimal mix), you get the same octane as buying Mid-grade and save $1.20. A couple of months ago, the savings would likely have been double this amount.



Is this a reasonable conclusion or is there something about ocance rating that confuses this result?

If you knew how much gas you needed before you started filling the tank (and were good at fractions) I suppose this would work. Seems like a lot of hassle for a buck, though, especially on a cold, windy day.

I just make sure I buy cars that run on regular.

I agree, it sounds like going through a lot of hassle to save a few pennies. Also what vehicles today require mid-grade? I know the Dodge Hemi powered vehicles recommend it. But every other vehicle that I know of either recommends regular or premium. With that said, Andy Rooney has never struck me as a gearhead, so I’m not sure if I would put too much stock in his automotive advice.

This works fine. It’s just a hassle.

The new hemi will knock no matter what octane fuel you put in it, and Dodge says that is normal!

The conclusion is reasonable, the inconvenience immense.

I like Andy Rooney. But he has to be taken very lightly. His editorials are meant as very light entertainment, not advice for living.

The sad thing about all this octane business is at least my locale the difference between buying premium vs regular has always been $0.20/more for premium. So now the difference as a percentage is greater since premium retails for $1.91/gallon vs regular at $1.71/gallon. This past summer premium was $4.09 and regular at $3.89.

Even back when fuel was $1.00/gallon I remember paying $1.20/gallon for Jetta GLI 16v which recommended it. Then I was really paying a lot more for it.

Mixing is fine. My wife does it on occasion if she is at 2/3 full with 93 she asks for regular. Her vehicle absolutely requires 91 octane.

Is Andy Rooney recycling his old commentaries? Or, is your friend just watching old ones on YouTube or something? I remember this rant of his from the early 1980s.