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Did I Pass Up a Bargain?

I stopped at an independent gasoline station this morning, because 87 octane was priced at $2.29 a gallon and this was the lowest price I had seen that morning. As I was filling the tank with 87 octane, I noticed a that there was a special and 89 octane was available at the same price. My vehicle, a 2006 Chevrolet Uplander only requires 87 octane. I don’t think for this vehicle that there would have been any advantage in buying the 89 octane, but I’m cheap and want to get the most for my dollar. Any thoughts?

It would have made no difference, so you missed nothing.

Everywhere I’ve ever been where the 89 octane is cheaper than the 87, it’s because the ethanol content is higher in the 89. So unless you’ve got a car that would benefit from the mid-grade, you’re almost certainly better off with the 87.

Thank you. The owner’s manual for our 2003 Toyota 4Runner says that the vehicle will run without problems on 87 octane, but that 89 octane may improve the performance and mileage. The owner’s manual for the Chevrolet Uplander makes no such claim. I’ve never used anything other than 87 octane in either vehicle. I have a colleague who has a Chrysler minivan and claims that his mileage is better with the 89 octane–enough that it pays the usual difference in price between the two grades. I’m a little skeptical of this claim.

There is zero to gain by using higher octane then the car needs. I might add that Greasy may well be right.

This reminds me of the continuing discussion abut synthetic oil vs. mineral oil. Almost none of us would benefit from synthetic, but there is a group that insist on using it anyway. I’d use whatever the manufacturer recommends. But check the compression ration on your 4Runner and Uplander and see if there is a difference. Higher compression would demand higher octane.

I have seen on the Internet a couple of years ago that some cars will run well on 87 octane as recommended in the owner’s manual but with the knock sensor and ECM will advance the ignition timing to take advantage of a higher octane fuel. It did not work for our late model GM car when I did my best to carefully check the fuel mileage, however, but it sounds a reasonable possibility or even a reality for some cars set up this way.

I may try the 89 octane as an experiment on our 2003 Toyota 4Runner to see if the mileage improves on highway travel. My wife always rubs it in that she gets better mileage with the 4Runner than I do when we are on the road. I’ll fill the tank with the higher octane when she isn’t looking. If the mileage improves on the 89 octane, I’ll refill it with 87 octane and then let her drive. I had a 1990 Ford Aerostar when my son was a teenager. The Aerostar was the top of the line and had a readout for gasoline mileage. My son always got better mileage than I did. Maybe the higher octane trick might have worked for me back then.

The oil area is a area all can play in,it doesn’t cost much and you can debate endlessly about the pro and cons of just about everything dealing with oil and oil changes,these features make it very popular,and most important, everyone has a opinion.