If it's more expensive, it must be better, right? But, is this really true when it comes to the octane in your fuel tank? Many people wonder if premium gas is really worth the extra $0.20 per gallon. It seems the answer isn't as clear cut as you would hope.
The answer is: It really depends on your car.
Here are a few tips to help you decide which fuel is best for your car.
Consult your owner's manual.
Some cars call for regular fuel, some recommend premium fuel, and some require premium fuel. The difference between "recommend" and "require" is key here. If your car calls for regular fuel, it is not worth it to put in "the good stuff." A car calling for regular octane fuel is designed to use just that. Putting in a gas that has more octane may improve performance and/or gas mileage, but it's up to you if it's worth worth the extra money.
If your owner's manual recommends a higher grade gasoline, you could use less than premium fuel but you could be sacrificing some performance and gas mileage.
If money is tight, it's not going to damage your engine, so you could opt for regular fuel. A better option would be to compromise and alternate between something less than premium and premium.
Do you own a sports or luxury vehicle?
While high-octane formulations resist knocking better than lower octanes, most engines are designed to take regular gas, which has an octane rating of about 87. Engines requiring premium gas are typically the more powerful ones found in sports and luxury vehicles. Those engines use a very high compression ratio, making them more vulnerable to knocking, so recommended fuels have octane ratings of 91 or higher. Using premium gas in an engine designed to run on regular doesn't improve performance.
If your car was designed for premium gas, you should use it.
No questions asked. These engines were designed to get more power out of smaller engines using a specific type of fuel, and if you use lower octane fuels you will not get that power you paid for. If you choose to use less than premium fuel in these tanks, it reduces efficiency and will cause damage over time.
So, is more really better? Only if required. If your car doesn't "require" you use premium fuel, it's up to you. It's not going to hurt your car if you opt for the lower octane fuel for the sake of saving a few bucks.
Sources: Edmunds.com, Car and Driver, Repair Pal
This post was originally published in 2014 and has been updated and republished.