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Octane Ratings

I own a 2006 Nissan Murano. Love the vehicle. The owners manual states that Premium Octane is recommended. At $4/gallon here in North Carolina, will I be harming my engine if I use 87 Octane gas?

If it says recommended…then it shouldn’t harm your engine.

Lower octane may cause your engine to knock. The knocking can DESTROY an engine. But modern vehicles are equipped with knock-sensors. They sense when the engine is knocking and then retard the timing. This reduce or eliminate the engine knock…HOWEVER…at the same time it’ll decrease performance and gas mileage.

If you buy a vehicle that is designed to use premium…then use it. You’ll save little or no money if you use a lower octane.

If it’s “recommended” you should be fine, albiet with some compromise in performance.However, if it begins to ping or operate abnormally, stay with the high test until you can determine the cause and if it can be corrected.

If it says “required”, than you’re screwed.

Calculate your gas mileage with a few tanks of premium, then calculate it with a few tanks of regular. You will probably notice lower gas mileage with the regular, then compare actual cost of the fuel to make sure you’re not spending more money just to feel good about saving 20 cents or so per gallon.

What are you saving? 3 or 4 bucks a tank? Say you average a tank a week. You’ll save only $150-200/year but not even that considering the probable loss in MPG. I’d bite the bullet.

Everyone else is right. If it’s recommended, you won’t damage anything by using regular, but you might get lower fuel mileage.