Which Gas Stations Sell the Best Quality Gasoline?

Which Gas Stations Sell the Best Quality Gasoline?

Oil companies and gas-station chains love to boast about their fuels, how they burn the cleanest or deliver the most miles per gallon. But can these claims ever be validated? How is the average consumer supposed to figure out what’s best for their vehicle? At least one kind of fuel cuts through the marketing malarkey. Top Tier gasoline is engineered to a higher standard.

Top-Tier Gasoline.jpgAnd it’s endorsed by several global automakers including General Motors, Toyota and BMW. Additionally, ExxonMobil, Chevron and Shell are a few of the oil companies involved. More retailers are listed in the graphic to the bottom left.

To earn Top Tier certification a fuel must pass four tests – deposit control on intake valves, fuel injectors and combustion chambers. Beyond that it must also prevent intake-valve sticking. Basically it’s gas with extra cleaning agents designed to keep engines running their best. Think of it as a housekeeper for your cylinder heads.

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Gasoline is an impure substance refined from a very impure base stock – crude oil. It’s an explosive hydrocarbon cocktail containing all kinds of different chemicals. In addition to its own molecular variability, refiners and retailers incorporate additional substances into the mix, from ethanol alcohol to octane enhancers. Still, gasoline contains even more additives, some of which are designed to prevent harmful deposits from forming inside engines.

Oil Companies.jpgTop Tier fuels feature more of these additives than regular gas. In 1995 the Environmental Protection Agency (EPA) set a minimum standard for gasoline additives. Since then, refiners and fuel blenders have actually reduced the amount of detergent they put in fuel by about 50 percent. In the long run this cutback has impacted the ability of vehicles to meet emission standards.

According to Bill Studzinski, Fuels Technical Specialist at General Motors, a number of OEMs saw this problem and got together to push for higher levels of detergency. He said Top Tier gasoline is a better fuel for engines, and that it takes the mystery out of what a good fuel is and what an average fuel is.

Chris Martin, a spokesman for Honda said “we’ve supported it [Top Tier gasoline] because we’ve seen a benefit from it for our consumers in the long run.” He also said the average driver doesn’t know about detergent additives, they just look for the cheapest gas available but “Top Tier fuel goes a step beyond that.”

“We don’t require that our vehicle owners use Top Tier gas” Martin said, but it helps “make sure the engines are going to last as long as they could.” This is obviously beneficial, especially since Honda drivers historically keep their cars for a long time.

Responding to questions via e-mail, Marie Valentine, the Senior Principle Engineer, Vehicle Regulation and Certification Engineering, Toyota Technical Center, said the amount of detergents in Top Tier gas is about twice what’s required by the EPA. However, it can vary depending “on the base gasoline and the chemistry of the detergent additive.”

When asked about the price of Top Tier Valentine wrote, “Toyota does not comment on the true cost. However, generally there is no change between TTDG [Top Tier Detergent Gasoline] and normal LAC [Lowest Additive Concentration] gasoline,” good news for consumers wanting to keep their vehicles for many years.

Top Tier is all about keeping engines clean. As far as fuel economy is concerned, it should perform identically to gasoline with lower levels of detergent, so don’t expect a big efficiency boost.

From a big-oil perspective Top Tier hasn’t necessarily caught on. Some of the largest players in the industry have adopted it including Shell, Chevron and Conoco, but not all.

ExxonMobile, the world’s largest oil refiner, is one of the companies onboard with Top Tier. All of their retail gasoline sold in the United States meets the standard, having received formal certification back in 2010.

Top Tier gasoline must contain more deposit-fighting detergents, it also must be sold at all of a fuel marketer’s stations and across all grades of its gasoline, from 87-octane regular to top-of-the-line premium. Additionally, to earn the seal of approval fuels cannot contain metallic additives, which are potentially harmful to automotive emissions-control systems.

Simply put, Studzinski said Top Tier gasoline is “a higher level of detergency, which keeps your engine running optimally.”

  • Wil

    This article fails to mention which Tier these companies adhere too.
    Are they speaking of Tier 1 or 2 gasolines ? I don’t think Tier 3 is in production yet

  • r demerse

    Does ultra mar gas contain ttdg

  • GD

    All I know is I drove from Dallas to Shreveport on Racetrac gas and used 3 quarters of a tank… I filled up at Valero on the way back and only used 1 quarter of gas… I don’t know how it happened that way lol that’s why I’m here… I do know, Valero my best friend now. We buddies!!!

  • deandre johnson

    shut up GD

  • jack68

    GD, maybe its an incline on the way to Shreveport and a decline to Dallas. there are many factors.

  • Phillip McMurran

    Who or what company is in charge of TT. Who tests the fuel to confirm the ratings? I looked at the web site and there was nothing about HQ. I clicked on history and linked to 76 site.

  • CES

    Most likely environmental factors such as wind, barometric pressure, temperature, and maybe gradual geographical elevation change.

  • CES

    I have researched this for months and I have even spoke with the EPA. The EPA doesn’t monitor gasoline detergent contents or advertising (that’s a matter for the Federal Trade Commission). In all these months, I have seen no scientific fact “top tier” gasoline is better for your automobile; only trendy corporate hearsay. Auto manufacturers and big oil may be working together to boost sales. If this is true, it makes sense why the auto manufacturers and big oil are pointing the finger at the EPA;’ plausible deny-ability.

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  • GayButtslutt

    Let’s do this

  • Mike

    When you drove to Shreveport was your tank topped off or were you simply watching how much the fuel gage changed? I drove a Dodge pu for years. The first quarter tank, by reading the gage, would go nearly as far as the remainder of the tank. The gage is merely a guide. You need to log mileage when you top off the tank and on each fill-up for at least 2-3 tanks from the same supplier for confirmation.
    And also take into consideration what CES commented as well.

  • Shnarf

    Were you towed halfway back?

  • Cliff Shaw

    Maybe you got a hold or real gas . non-ethanol fuel….my mileage is ALWAYS better when I’m not running with fuel that has ethanol in it.

  • len

    I like spaghetti

  • HyundaiMan

    I believe Costco has Top Tier gasoline also. But I am trying to figure out where does Costco get their gas from? Does anyone Know?

  • Me

    all about $$$$. the top tiers are unaffordable. I use Vlero and have never had issues and they are 20 cents lower

  • Aaron Lavender

    We don’t have 87 octane here in Utah. We have 85 88 and 91. Does Exxon’s,Chevron’s, Shell’s…etc…. 85 octane meet top tier standards?

  • CMGZ510

    Tesoro here in SF BayArea

  • sasquatchburrito

    It is still a Top Tier gasoline. To receive Top Tier status, a manufacutrer must meet the Top Tier requirements for all locations nationwide. Utah has lower octane because it is a high altitude market and engines have different requirements at higher altitudes.

  • Filip Jakacki

    I actually notice a difference with higher tier fuels. I used to only out the cheapest gas but one time I was out so I stopped at Shell and filled up. I swear I got at least 60 miles more on a full tank, the car drove smoother, and was just overall different.

  • Salazar Paula

    Yes all gas is the same,but I have a friend that’s a truck driver &delivers gas to different places&the stated that all gas has different chemicals,Valero,Aziz,Murrphy,HEB, are all generic gas the best one at top tier are Cheveron,Shell,Texaco,Philliphs66,etc cuz they have more detergent in it to clean the motor,&true,I filled up with Cheveron to take a road trip&went all the way to Austin on a half a tank normally using Murrphy etc I go from the valley to San Antonio,on a half a tank or a little bit more.

  • Imogene Clymore

    I didn’t see Quik Trip on here, just Kwik Triip. In Oklahoma, we have Quik Trip (QT)

  • Gronski, CD

    So, the question is, “What is the ‘best’ quality gasoline?” Still not answered.

    Break it down by octane level and part(s) of the country (Canada/USA) you’re in as well if required.

  • Morgan Kemp

    If you go to maverick, then you will get all the way down below 85 and up.

  • flacoface

    Yes, Costco is top tier.

  • ThomasXxs

    It may be true that all gas for a certain area is the same PRIOR to adding the additive/detergent package for each brand (some of these gas additives even have a name and are also sold separately, like Techron for Chevron/Texaco gas or that Nitrogen-based detergent in Shell gas). As you say, the brand-specific additive packages are put into the gas by the truck driver making gas deliveries to different stations on his route. I’m not sure about the exact method for doing this.

    For one example, I understand that nearly all of the gasoline in the Carolinas and much of the southeast comes from a huge gasoline pipeline that pumps gasoline only, from southwest Louisiana to 2 major end-points near the East coast: one near Spartanburg, SC and the other one in northern New Jersey. The gasoline in this pipeline is a mixture of the output from something like 10 large oil refineries in the Texas-Louisiana Gulf coast area, with several of them near Houston. This pipeline system and others like it are probably the basis for claims that all gas is the same. It is in fact all the same coming out of the pipeline, but this is before the addition of the additive/detergent packages for those brands that improve on the minimum federal standard (such as the Top Tier brands). I’ve read in car magazines that many consider Chevron and Shell to be the best brands. I don’t know how true this is, but I did hear that Chevron was the only brand to meet Top Tier specs without making any changes.

  • ThomasXxs

    I believe that “5x govt req” is what Shell claims about their Premium unleaded gasoline (93 octane in my area). I’m not sure if this 5x claim also applies to Shell regular unleaded gas. I have not seen that stated.

  • ThomasXxs

    The auto manufacturers backing Top Tier (BMW, Audi, VW, Toyota, Honda and GM) all report having long-term studies showing that their engines perform better and last longer with optimal levels of detergent additives in the gasoline (as provided by Top Tier specs). I don’t see what these manufacturers really have to gain from this, that is not also advantageous to their customers and their cars.

  • ThomasXxs

    There is no such thing as Tier1, Tier2 for gasoline. It’s either Top Tier or it’s not. It’s only been around for maybe 10 years or so. Apparently the standards for detergent levels in gasoline were lowered by the federal government around 2003, and Top Tier was the response of several major car manufacturers.

  • ThomasXxs

    While it’s true that unleaded gasoline contains more energy by volume than ethanol (resulting in somewhat better mileage) the ethanol does tend to improve the octane value, thereby making the ethanol blend less prone to pre-detonation or pinging (in the same way as Premium gasoline does). If you are suffering from excessive pinging with the non-ethanol gas then potentially expensive damage to your engine could easily outweigh any savings from slightly better mileage. Plus, in my area the ethanol-free gas (from Wal-Mart and Quik-Trip) is much more expensive than the regular unleaded gasoline.

  • Cliff Shaw

    87 octane is 87 octane regardless if it’s in ethanol or non-ethanol fuel. The only reason one would need a higher octane fuel is if the owners manual states that their vehicle requires higher octane fuel do to higher compression designed motors. An 87 octane non ethanol fuel will ping just as must as an ethanol laced fuel if used in a higher than “normal” compression motor.

    Overall…..the few cents one pays for non ethanol fuel is worth the extra $$ as you’ll get better gas mileage and more performance from your vehicle.

    Ethanol based fuel is a HUGE government scam.

  • Challenger RT Mopar

    I was talking about how much additive Costco adds to their raw gasoline… Costco purchases raw gasoline (usually Tesoro here in SF Bay Area) meaning without any extra addictive from any place or other company. Yet as of two years or so ago Costco has added their own blend of detergents to the raw gasoline from their place of purchase, adding up to 5x the government requirements to meet the “Top Tier” standards… I have witnessed Costco purchase raw Shell branded gasoline and mix their own additive(5x gov. Standards) and sell it as Kirkland Signature Gasoline both premium and unleaded octane. Costco has very good gasoline is what I was saying… LoL

  • Homer J. Simpson

    QT is a big player here in Texas because they tend to be cheaper than the competition. I used them almost exclusively due to their price and accessible location. After about a year my car developed sluggish acceleration and frequent cold start misfires. A little research helped me determine it was most likely carbon buildup. I switched over to Chevron and within about 3 fill-ups the idle was noticably smoother and the misfire prompted check engine lights went from daily to less than once a week. Although I have seen QT listed in some publications as Top Tier, I let my experience speak for itself.
    (After running a can of Seafoam through the gas tank I haven’t seen a check engine light in 2 months. I continue to use ONLY Chevron.)

  • William E Hoyt

    My dealership (Hyundai) informed me that Costco has the worst gas on the market. Evidenced by clogged injectors by faithful Costco gas customers. I don’t see Costco listed as a top tier distributor. Any comments?

  • Pete Olivarez

    How is Valero Stripes gas?

  • Akin Berry

    I’m a big fan of Chevron gas. The quality stands out from 76 gas stations (nearest to my home) and its not as crowded as Costco gas stations. Also they are tech friendly. They allow you to use Apple Pay tap system to pay at their stations. This cuts costs by reducing the paper receipts at stations. The annual fee to use Costco is $110. By going to Chevron and avoiding Costco’s annual fee, I save $6 per year based on my annual car gas consumption. I also avoid very time consuming long lines.

  • Fleming_007

    My mechanic swears on using Chevron, Mobil, and Shell only. Everything else he says isn’t real gasoline for example Arco is shit and will clog fuel injectors way more than normal use.

  • charles

    that gas burns faster not that good to me

  • Tyler

    I’ve had alot of luck using Costco gas

  • JeezHchrist

    I miss the days not too long ago where you could buy 96 thur 102 octane gas from some stations in orange co Ca
    These days I usually buy Shell and if you shop at Ralphs you get 20 cents off per gal

  • Velvet Jesus Elvis

    Costco gas is Top tier.

  • Bob Smith Sr

    how come Gulf Gas is not on the list for top tiers??

  • Bob Smith Sr

    I use gulf from three different companies and have better luck with gulf then i do with Mobile – with Mobile i loss gas Mileage – when i use gulf i regain my gas mileage. who figures

  • ThickNjustrite Too

    I’ve tested all the top brands, & got the best performance overall using #1-Bp(Amoco), #2-Exxon. Both have the highest octane (93) & I can feel a real difference using either/or.

  • Charlie Perrin

    Top Tier is a registered trademark of General Motors. They sell access to the test rigs used in the certification testing.

  • Charlie Perrin

    There are EPA tiers of gasoline. Everything you get outside of California is Tier 2. Everything you get in California is Tier 3. It’s different that Top Tier, which is a standard controlled by General Motors.

  • craigdonahue

    I have been driving Mercedes and Jaguar for 20 years and every time I use a discount gasoline like Walmart, ext. for any length of time I have to replace my mass airflow sensor. This happened about three times until I realized I need to use only a quality company which I choose She’ll.If I can’t get to She’ll I use Chevron or Exxon.Since then I haven’t replaced a mass flow sensor in either performance car!

  • craigdonahue

    You must not care about your car.

  • craigdonahue


  • Velvet Jesus Elvis

    B/S? Costco is listed as a Top Tier detergent gasoline.

  • Tyler

    Literally have ran costco 93 for 2 years and had no problems. I prefer Shell V Power though

  • BillyHW

    Costco is listed as a top tier gas retailer.

  • Pirasa

    It is very funny that you call 93 as highest octane in US and we have 95 lowest in Turkey and gas prices are extreme. We use liter in Turkey instead of gallon after converted to gallon the price is $5.6/gal. 95 and 97/98 octane is almost the same price. I think we are using the most expensive gas in the world but quality is also higher, worth it? of course not 🙁

  • Thomas Johnson

    That’s not true in most areas of the USA – the prices of gas and diesel at Top-Tier stations are about the same as at non-Top-Tier stations. BTW, the last time I checked Valero was still NON-Top-Tier.

  • Thomas Johnson

    I don’t think there is any such thing as “raw Shell” gasoline. Shell gas is all Top-Tier and this requires that all of their blends meet the specs. Even the brands that are not Top-Tier still contain some detergent additives (as required by Federal law in the USA) but the additives are present in lower amounts and their detergent mixes are (possibly) of lesser quality than with Top-Tier brands.

  • Thomas Johnson

    You might not notice the issues of concern. But your engine will not run as well or last as long with use of gas having inadequate levels of detergent additives – as was proven in long-term engine tests done by the automakers who started Top-Tier (VW/Audi,Toyota,Honda,GM…)

  • Thomas Johnson

    If Chevron gas is good, then so is Texaco gas, since it contains exactly the same Techron mix of fuel additives. In the same way, if Mobil gas is good, then Exxon gas is too….

  • Thomas Johnson

    That’s not really correct. GM was one of the automakers that formed TT, but other major companies were involved. Each detergency package is validated at an independent ISO 17025 certified laboratory – and NOT at “test rigs” controlled by GM

  • Thomas Johnson

    You should take a closer look at the TT website. It mentions a CQA “Center for Quality Assurance” group which is involved in all testing and certifications.

  • hunger strike

    Octane ratings are obtained differently in different parts of the world. The Turkey octane rating is probably RON while the US uses (R+M)/2 method. US 93 is about 98 RON octane.

  • Brian Lee

    For some reason when I use Costco gas my car vibrates more at idle. There is a distinctive knocking that I dont get when I fill up with Chevron.

  • Granville Graves Sr.

    Costco is a Top Tier brand.

  • Dylan

    Mass airflow sensor is air coming into your engine. The fuel going into the motor will have no effect on damaging the mass airflow sensor. They don’t mix. If you told me your O2 sensors went out more with crap gas, or catalytic convertors, maybe.

  • gluttenReader

    When I get gas from another station, It doesn’t last as long as QT. I’m starting to think OT has better gas than my usual place top teir AMPM.

  • squared

    I also buy Shell and get my discount by shopping at Fred Meyer. There is one Shell station on my commute that is 30 to 60 cents cheaper than all the others around, even before discount.

  • stangGang

    Costco gas is on top tier because they make good business. Their gas quality is really poor if u do research on it

  • Velvet Jesus Elvis

    What does “because they make good business” mean? Also, where in my previous post did you read that I think Costco has good gasoline!

  • Velvet Jesus Elvis

    Top Tier Detergent gasoline is not controlled by General Motors.

  • Charlie Perrin

    Who do you think owns the Top Tier brand? General Motors. They also own the Website.

  • Charlie Perrin

    BP and Exxon are now claiming that their particular flavors of gasoline result in improved fuel economy.

  • Charlie Perrin

    Utah is one of the places where 85 octane is sold as regular unleaded. However, many fuel injection vehicles require a minimum of 87 octane at all altitudes. I’ve never driven in an area where 85 octane is sold as regular.

  • Charlie Perrin

    Valero recently jumped on the Top Tier bandwagon.

  • Velvet Jesus Elvis

    All I know is that it was started in 2004 by Honda, Toyota, BMW and GM. They adopted standards from the Worldwide Fuel Charter. Volkswagen, Audi, Mercedes-Benz and Fiat Chrysler all joined the group in the years since.

  • Charlie Perrin

    Valero fuel recently went Top Tier. Stripes is a C-store chain. Although they are probably going to change over to Sunoco fuel (which is NOT Top Tier as of the last that I knew). Stripes is owned by Energy Transfer Partners, the owners of the Sunoco brand in the US.

  • Charlie Perrin

    FWIW, $5.60 per gallon is not the highest priced fuel in the world. Norway is close to $10 a gallon.

  • James W

    My father buys the cheapest gas possible. He has this ancient Chevrolet van that uses an archaic throttle body injector system that runs just fine on it. I have a new Chevrolet that just loves Shell gasoline. I get a few more miles per gallon using that brand, So that’s what I buy.

  • James W

    Costco IS top tier gas BUT the gasoline stock is of varying quality. They buy from refineries day by day on who’s the cheapest that day. They they load it up with the additives to make it top tier gas. That’s how most gasoline is sold nowadays.
    Sometimes the gasoline has dirt in it or water. Name brands like Shell, BP, Mobil etc get the first run and the lesser grades go to the discount and generic brands.
    Where I live in NJ there is one huge refinery that makes the raw gasoline. Then the trucks come in with that brand’s detergent package already in the tanker.

  • Billy H

    I am one of those great drivers that has delivered gas to your local service station. When the driver pulls up to the loading rack ( as its called) you will hook up a vapor hose to the vapor tube. you will hook up the loading hose from the loading rack to what is called the loading head on one of the four or rarely five trailer compartments which holds the fuel, whatever it is. You will insert your ” fuel card in to the computer slot. You will type in your passcode and start the order. a very, very long list of stations are waiting for you to type in a station number. You will type in the product, and the grade, the gallions, and whatever info might be needed ( truck number, trailer number etc.) On the premesis of the loading rack are several large tanks which can contain everything from gasoline to additives, to which once the fuel starts flowing from the storage container, different additives can and do flow from the some of the tanks on the premesis. Yes the GAS may all be the same, however the additives and amounts can and do differ.

  • Daniel Ardeline

    ? The octane requirement decreases equally with altitude for all vehicles because of the air pressure differences. The octane recommendation in the owner’s manual is based on tests are done at sea level.

  • sayahh

    Correct. Turkey 95 RON is about 90 (R+M)/2.

  • John Yurglic

    I have too. They have the fastest pumps because they change the filters regularly. Last year they were one of only 4 top tier gasolenes. When not near Costco I use shell.

  • Scott

    Its funny how everybody is equating gas mileage to good gas. Good gas keeps your engine clean and helps your engine to last longer. You may get better gas mileage with a certain gas but it may not have the special additives to clean your engine and will shorten the life of you engine in the long run. Interesting article.

  • Samson – have a great day

    I talked to someone in oil industry and was told that Costco uses as much detergent additives in their gas as shell v

  • Aaron Lavender

    I had my car tuned to 91 octane to get a few extra HP. That’s a second reason. Yes, for most car owners, they should follow the octane rating in their vehicles hand book, or what the manufacturer states.

  • Steve Williams

    Do you really trust using Walmart gas ?? LMAO I bet you use the cheapest Walmart oil / filters when doing oil changes. My Trans Am has the same engine LS1 as the Corvettes and uses Mobil oil-the best. I only use Mobil oil/ filters and Mobil gasoline. The best deserve the best. But then again you probably drive a foreign made econo car not a performance car. I get 18 town/ 26 highway gas mileage. Only 91,000 miles for a 1998 vehicle with a 5.7 liter/ V-8~ Smooth idle and power like new with original spark plugs

  • Jeff Lancaster

    I’ve got an Italian word for your comment, balogna! The mass airflow sensor does just that, senses airflow and gas never comes in contact with it.

  • Kathy Mirick

    I bought unleaded gas from the unleaded pump and got diesel instead. This was a long time ago. The truck operator that delivered the gas put the wrong gas in the wrong tank. It messed up my engine. They paid to fix it.

  • Kathy Mirick

    I use the best gas I can find locally, which is only 91. They used to sell 93 here but do not anymore. I live in the sticks, a long way from other cities. I drive a Smart Car and scooters. I would not use anything but the best in them. I have NEVER had one problem in 8 years with my car. I even put high grade gas in my lawnmower. I do not understand why someone will pay 20,000 to 60,000 for a new vehicle and run the cheapest gas they can find in it. I buy from Shell or Exxon. NO CHEAP GAS IN MY BABY.

  • Kathy Mirick

    Pirasa. I wish we had 95 here in the USA. The highest we have is 93. We pay more for the 93, but I am willing to do it. The 91 here in the USA is $2.99 a gallon, so I would rather pay a little more for 93 or higher. Unfortunately, where I live, you can only get 91. I do not understand that. Hard to believe NOBODY in my city uses better gas in their expensive cars and trucks. The extra cost is worth it in the long run because it will help your vehicle last longer. Wow, 98 octane would be awesome. People in the USA are cheap. Even the ones who drive very expensive cars and trucks are cheap. People here live in dumps and drive a $30,000 car. GO FIGURE???

  • Rick

    I use only Mobil or Shell in my Harley anything else I notice the difference..premium of course..