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So you're at the pump trying to decide what kind of gas to use. You see different numbers on each pump but you're not a mathematician, you just want to put some fuel into your vehicle. Let's get a little background on your options at the pump and how they affect your car.
What do those numbers on the pumps mean?
The numbers on the pump (ex. 87, 92 or 93) refer to the octane level of the gas. 87 is considered regular gas while 92 and 93 are considered premium. The octane level (or octane rating) is an indicator of the performance of the fuel. The higher the octane number, the more compression the fuel can withstand before detonating
What is the difference between premium gas and regular gas and why should I care?
Premium gas has a higher octane rating than regular gas. Gas with a higher octane rating is designed to prevent something called "knock" on cars with high compression-ratio engines. Knock occurs when your gas ignites prematurely, causing your engine to make sounds similar to knocking. You don't want your car to knock, so it's important that you use premium gasoline if your car has a high compression-ratio engine.
How do I know whether I need to use premium or regular gas in my car?
The long answer is that it depends on whether or not your car has been designed with a high compression-ratio engine. The short answer is check your vehicle owner's manual. Your manual will tell you whether or not your car requires premium or regular gasoline. The good news is that most cars are designed with a lower-compression ratio so regular gas will usually suffice. Typically the only cars that require premium gasoline are luxury cars.
Should I use premium gas if my owner's manual doesn't require it?
No. There is no proven benefit to using a higher octane gasoline in your car unless it's required in the owner's manual. You'll be wasting money for literally no reason. Some companies advertise that using their premium gas has the added benefit of cleaning your engine, but this is misleading marketing since the EPA requires all gasoline to contain engine detergent, no matter the octane level.
Now that you're a gas expert, feel free to explain everything you just learned to strangers pumping their gas next to you.
