QuestionI have a 2001 Chevrolet Tahoe with 5.4 L V-8. The owner's manual calls for 87 octane unleaded fuel and the car runs fine on this - no ping / knocking, etc.
Someone told me if I use 89 octane or 91 octane fuel it is better for the car and that I will get better gas mileage.
What's the deal on the different octanes? Should I spend the money to use a higher octane than the recommended 87 grade?
Thanks.
AnswerHi Jim,
If you are willing to experiment a little, try a tank, and see what mileage you get, along with the performance.
If the mileage increases enough to justify the difference in cost, then use it.
As for the low octane not pinging...well the knock sensor on the engine would retard the timing to prevent the ping before you ever hear it, but the loss in power might be noticable, even though you can't hear a ping.
But the "ping", or "knock" from low octane fuel is what would hurt the engine. Fortunately, the knock sensor compensates for that, so power and performance are the criteria you have to go by.
Van
