Does a car last longer if you use premium gas instead of regular?

Dear Car Talk

Dear Car Talk | Apr 01, 2000

Dear Tom and Ray:

I was wondering if a car lasts longer with premium gas instead of regular unleaded? If I use regular unleaded instead, will the car die faster? My car is a 1991 Pontiac
Bonneville. -- Emily

RAY: The only way premium gas can extend the life of your car is if you submerged the car in it, Emily. That'll at least keep it from rusting.

TOM: But in terms of what you put IN the tank, the answer is no. Unless your car specifically requires premium gas (which a few cars with high-compression engines
do), premium is a complete waste of money.

RAY: Over the years, consumers have been led to believe that "premium" gasoline gives you some sort of "premium" performance. But that's not true. Engines are
designed to run on fuels of particular octane. You need to use at least that octane to prevent pinging, but using a higher octane than that is simply unnecessary and, in
fact, increases pollution.

TOM: This is an imperfect example, but think about how much water you drink on a daily basis. Doctors say you should drink about eight glasses of water a day. If you
drink 28 glasses, is it going to make you healthier? Probably not. It won't hurt you, but you'll just, uh ... relieve yourself of the excess.

RAY: The same is true of premium gasoline. Your car CAN burn it, but it doesn't gain anything from the higher octane.

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