Does the quality of gas for your vehicle vary depending on where you buy it? An expert weighs in.

With gas prices sitting at high levels, many people know where to find the cheapest fuel in their neighborhood. But do you ever give a thought to the quality of what you are buying and whether or not it makes a difference? 

First of all, know that not all gasolines coming out of the pumps are the same.

Many people just want to know that the wheels in their vehicle are going to keep on rolling, no matter what fuel they buy. 

"All gasoline is generally produced to a federal standard," said GasBuddy.com Head of Petroleum Analysis Patrick De Haan. "All gasoline, required by the federal government, must have a certain level of detergents to keep your engine clean."

It's after the baseline requirements that come the differences.

"All gasoline is coming from the same refineries," De Haan said. "The difference between retailers may simply be a slight additives package that's blended in."

De Haan said that if you watch tanker trucks go into the bays to fill up, it may look like they're pulling the same products, but they're likely putting additives in the fuel that you may not see.

When you go to the pumps, you can see different things that different companies advertise to differentiate themselves from other retailers.

"There are minute differences in the amount of additives contained in gasoline," De Haan said. "Top Tier is a certain program with additional additives."

In most cases, it's more of the additives the base gas already contains, and you may pay a few cents more for the additional engine cleaning, which De Haan says is a good thing.

"There are very few cars in the junkyard that have failed over time because of fuel deposits," De Haan said.

De Haan and a reputable mechanic agreed that engine failure mostly comes from neglect, not from a lack of fuel additives, which can't be considered a waste of money, as some high-performance vehicles will benefit from a cleaner-running engine.