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What Is Top Tier Gasoline In And Why You Should Only Use It In Your Toyota Prius

When it comes to gasoline options, there are many. What many consumers just do not know is why using top tier fuel is actually better for their car in the long run even if it costs a few cents more per gallon. Here are the facts about using the best quality fuel in your Toyota Prius.

When it comes to taking care of your Toyota Prius gasoline is one of the first line of defences. Even though Prius is a fuel miser, it still does consume gasoline. Many owners out there have hundreds of thousands of miles on their cars and are expecting to get hundreds of thousands more.

Gasoline is not created equal amongst fueling stations and most people (even me until I really began to dig in and learn about this) find the cheapest possible fuel to try saving a buck. That mentality will actually cost you more later on down the road, but before I explain why we first need to know what top tier fuel even is to know why it is better than the other stuff.

What Is Top Tier Fuel

Gasoline (and diesel) is the lifeblood of our society, without it all transportation we know of would cease. Fuel is stored in major areas by various retailers sending tankers to large containment facilities. When a fuel station needs fuel, they send a tanker that has the required additives that go into the fuel to make it their own. For instance, if Chevron sent out a tanker, that tanker would treat the fuel with Chevron's Techron and then pump it into the ground at a local fueling station. So, this begs the question, is all fuel just the same stuff with different additives? We should dig a bit deeper.

Gasoline fuel pump nozzle station

Back in 2004, Top Tier Fuel was developed to go above the minimum requirements for gasoline additives. Gasoline detergents, which help protect our highly developed engines, are there to reduce carbon build up on intake valves and hopefully on pistons as well. This level of cleaner fuel helps with smoothing out engine idle, hesitation, knocking or pinging. It also will help improve the fuel economy as well.

As our technology has improved over the past 2 decades, engines, like what we see in Toyota Prius, have become more sophisticated. Hybrids are cars that were designed to achieve cleaner emissions and get the best possible fuel economy as well. Other automakers along with Toyota have been supporters of making Top Tier gas available everywhere, even recommending it in owner manuals to vehicle owners to let them know how to take care of and get the best performance out of their car. Also, getting owners to buy in to the fact that Top Tier fuel helps keeps engines cleaner, this would reduce the probability of bigger problems.

Top Tier fuel simply put is quality, high detergent gasoline, available in all octane grades, that Prius owners (and others) can use to get the most out of their vehicles.

What Would Using Top Tier Fuel Do For My Prius?

When the fuel was lab tested, an engine ran about 100 hours to give a representation of close to 4 to 5,000 miles of real world use. After that, the engine was disassembled and inspected to see the amount of carbon deposits that were left behind. Basic gas sources were selected and 6 fuels were created to use in this research. Each had different additives that varied the results from each fuel.

Overall, the Top Tier fuel had nearly 20 times fewer carbon deposits on hard parts like intake valves, injectors, pistons, etc., compared to standard fuel. Simple information like this really can make owning a Prius much easier.

By, reducing intake valve deposits by 45 to 72 percent this means that you will see less drag and resistance in the intake swirl pattern. This will help make the combustion more complete and result in better fuel economy. Results will vary due to the different detergents used by different brands.

fuel additives being mixed in glass beakers

Gasoline from a Top Tier Fuel station and a standard station could be a range of about 5 cents per gallon difference. The real question is what will you gain from using Top Tier, probably about 2 miles per gallon. In a Prius that makes quite a bit of difference if you are really trying to hypermile and get the most out of you car.

Where Can I Get Top Tier Fuel For My Prius
Any of these fine establishments as listed below currently sell Top Tier fuel. Chevron, Shell, Conoco, Costco Wholesale, Marathon, 76, Sinclair, Texaco, Exxon, Phillips 66, Valero, MFA, Esso and BP. There are probably A few I am missing, but this covers the major ones.


For the minimal investment of about 50 cents per 10 gallons, gaining 2 miles per gallon and keeping your engine cleaner can be a great investment in the long run. Especially since that will add up over time, and your Prius will love you for it.

I hope that you have enjoyed reading about using Top Tier Fuel for your Toyota Prius. Check out my other story Why the first generation Prius is better than either generation Nissan Leaf.

See you in the next story where I am discussing why the Toyota Prius AWD-e is the best one yet and why car enthusiasts and average car guys loathe the Toyota Prius. Also see my recent story where I am discussing the refueling costs for Tesla Model 3 vs Toyota Prius.

Also Watch New tech means more MPG from your Toyota Prius and Click to Subscribe to Torque News Youtube Channel for Daily Toyota Prius and Automotive News.

Peter Neilson is an automotive consultant specializing in electric cars and hybrid battery technologies. He is an automotive technology instructor at Columbia Basin College. He holds a Bachelor of Science in Automotive Service Technology from Weber State University. Peter is also an Adjunct Instructor of automotive technology at Columbia Basin College. Peter can be reached on Linkedin and you can tweet him at The_hybrid_guy on Twitter.


warren trout (not verified)    September 5, 2019 - 11:13PM

Where in the world do you get top tier gas for only 5 cents a gallon more?! In Seattle it is closer to 30 cents.

My Corolla is 22 years old with 260,000 miles and I beat EPA estimates with the cheapest gas and oil I can find.

Bryan Wilkins (not verified)    September 5, 2019 - 11:34PM

If you are going to open this can of worms. Is 10% or 15% ethanol good or bad. and what octane level should you use. Kwik Trip in the upper mid west sell top tier gasohol. Many people think the ethanol is a engine killer. High elevation states cut octane to 85 in the summer to cut down on pre-ignition.

Bryan Wilkins (not verified)    September 6, 2019 - 3:59AM

Is 10% or 15% Gasohol good or bad? Kwik trip and Kwik star stations in the midwest sell Top Tier pure gas, Top Tier 10% ethanol, and Top tier 15% ethanol. Which is best? I remember when Ethyl Anti-Knock was the in thing. Then lead free came and didn't hurt anything. Then again I remember when tire rotation included the spare tire.

MattyD (not verified)    September 6, 2019 - 7:37AM

In reply to by Bryan Wilkins (not verified)

You had one spare tire? My Chrysler Cordoba had room for 4 full size tires, a homeless family and a tiki bar in the trunk. Always got an interesting look when offering a police officer a drink after getting pulled over

Vincent J Baker (not verified)    September 6, 2019 - 10:08AM

This is totally at odds with the instructions given by the Toyota Dealer. They said "Only use Regular Gas", curious....

Prius Owner (not verified)    September 6, 2019 - 4:28PM

Costco gas is on this top tier list? Not from what I've experienced. In my previous car (before my Prius), I ran three tank full of Costco, and then three tank full of 76. There was enough difference in mileage to make the 76 gas actually cheaper than Costco. But don't just take my word for it, run your own test and see the difference in mileage.

jet (not verified)    September 1, 2020 - 3:25PM

What would you recommend for a RAV4 Prime (since the gas likely will be in the gas tank for a long time due to using it in the EV mode)? A top tier E10 or a non top tier ethanol free gas? I would also appreciate your reasons for your answer.

Dan (not verified)    October 12, 2020 - 1:03AM

I asked a Costco attendant about their top tier detergent gasoline. He said that costco has 10x the minimum detergent designation necessary to be classified as a top tier gasoline. Possible that extensive detergent isn't as flammable as gasoline causing slightly less gas mpg. Back to the Prius, they are famous for clogged egr ports and tubes. The better detergent gasolines will inhibit buildup of carbon in the egr ports. Pay now or pay later. Clogged egr on prius is a precursor to the notorious blown head gasket in 3rd generation prius. The consultant in this article is 100% correct.