By on July 7, 2016

AAA Fuel Test

AAA hired an independent lab to complete 4,000 miles of simulated driving to compare Top Tier gasoline with the cheaper blends. Their findings show that the additive packages in Top Tier gas resulted in fewer carbon deposits than those found in the non-Top Tier gasoline test.

The study also found that there were some secondary benefits to the better additive packages, including slightly better fuel economy and better drivability. The benefits are apparent, but do consumers really care?

The Top Tier gasoline specification was created by a group of automakers in 2004 in response to the minimum gasoline detergent standard introduced by the EPA in 1995. The EPA standard was designed to meet emissions targets but didn’t account for engine longevity. So, automakers created a new higher standard to prevent long-term issues such as clogged fuel injectors and contaminated combustion chambers.

Top Tier gasoline is widely available and can even be found at wholesale retailer Costco. Most gasoline comes from similar sources and is transported along the same pipelines until it reaches a local distributor. The distributor sells the gas to local stations and blends in an additive package based on the brand and specification. Some gasoline gets a very basic additive package but Top Tier gas gets a very specific package that has been tested to meet the Top Tier standards.

According to the AAA study, the non-Top Tier fuel caused carbon deposits that were 19 times higher than the deposits from the Top Tier fuel. They also saw better drivability and better fuel economy when the better fuel was used. Emissions were also reduced, likely due to the ban of metallic additives in Top Tier fuel.

Valve Carbon Deposits AAA

The laboratory completed the test on a Ford port injected 2.3-liter engine, which appears to be the Lima engine from the late 1980s. This engine has been used for testing for about 15 years and is a popular one, due to the orientation of the valves (which shows the difference in carbon deposits in just 100 hours of testing). The full report shows compares the average 34.1 milligram carbon deposit in the Top Tier fuel test to the average 660.6 mg carbon deposit in the non-Top Tier fuel test.

The technical results are clear but the second part of the study looks at whether they really matter to consumers. The AAA survey found that 63 percent of drivers who responded believe that quality of gasoline differs between retailers, but only 12 percent use the additive package as a deciding point when making a purchase. The two main things that actually drive purchase decision are the location of the gas station and the price of fuel, with almost three quarters of respondents saying those factors motivated them the most.

Although the study makes it seem like your engine is doomed if you use lower-level fuels, there is an upside. Switching to a Top Tier gasoline has shown reductions in carbon deposits on an engine previously run on lower level gasoline, and the cost difference to switch is only a few cents per gallon. It may be worth it to make the jump.

[Images: AAA]

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102 Comments on “AAA Study Finds Drastic Differences In Gasoline Quality...”


  • avatar
    Parousia

    This is who has Top Tier gas.

    http://www.toptiergas.com/retailers/

    • 0 avatar
      Rick T.

      Thanks!

      Looks like I will be going back to buy more gas at Costco rather than Sam’s.

      • 0 avatar
        kengland45

        That’s precisely what *I* thought, Rick–and I’d be curious to know how you’ve fared.

        We were using Sam’s Club 91 octane in ’14 Honda Odyssey V6 and my ’95 Nissan Sentra–it seemed no different than the 91 octane Chevron we’d always used. In the last Sam’s tank, we switched to 87 octane on both (by this time, I’d traded in the Nissan for a ’14 Honda Accord 4 cylinder. Last week, I filled both up with Costco 87 here in Long Beach.

        Right away, the Honda had hesitation. And it was louder–especially at higher revs and downshifting/sequential mode. It was a really hot day (100+ degrees), and I *did* have the A/C on–but there was an immediate difference. Oddly, the oil change light came on. It’s probably unrelated, and a call to the dealer said the oil had been changed 6 weeks earlier–reset it. It feels weaker, though–especially up hills.

        I added a K&N drop-in air filter, and had an immediate 3-4 MPG gain (city)–and power. There was no drop in MPG going to Sam’s. But the Accord has started making a clock-like regular clicking noise it wasn’t making before. It was an extremely well-kept car with a beautiful finish, and very smooth-running.

        So what happened? The dealer thinks “bad gas.” I had switched to a lower octane, so maybe it started affecting the car (and the previous owner was using 91 maybe). I know switching to a lower octane could cause knocking.

        I bought some Techron for both cars and the next fill-up. I think I’ll try Costco 91 since both cars have been weaned on it. My Nissan immediately ran smoother and more powerfully on 89 and 91 octane–since it was new. It seems like no one else here has experienced that, or just paid attention to price and location more.

        I’ll probably try a small amount of Costco 91 without the Techron just to see if there’s a difference. Sam’s Club isn’t Top Tier, but it seemed like the Accord’s power went UP when I switched from Sam’s 91 to Sam’s 89.

        All this is driving me nuts. Any help or insight would be greatly appreciated!

    • 0 avatar
      Von

      What? A first comment that is relevant? AND useful?

      Mind. Blown.

    • 0 avatar
      Lincoln

      I was using costco gasoline and getting bad gas milage, then in early September I filled up with ChevronI was getting four more miles to the gallon. That was a years ago last September. I went on vacation and filled up at the premium stations and got as much as six miles to the gallon more. When i got home the first of October I filled up at that same station and my milage dropped four miles to the gallon. I might add that I live in southern California and have not got that kind of millage since. I went to Arizona last July and as soon as iI filled up in Arizona my gas millage jumped up four miles to the gallon. I might also add that our gasoline costs fifty cents to a dollar more a gallon. This is what you get then you have Moonbeam gasoline.

  • avatar
    Geekcarlover

    What makes a difference? $$$ The station nearest my home is 17¢-20¢ more than the one near my job. I’ll leave early and fill up on my way into work.

  • avatar
    VW16v

    Costco gas seems to be the best quality. At least when it comes mpg.

    • 0 avatar
      MBella

      I think the advantage with costco fuel is the frequency at which they sell the fuel. The stations are always busy, which means the tanker truck is constantly refilling the stations with fresh fuel. Most name brand stations are top tier these days. I would regularly avoid ones that are not though.

      • 0 avatar
        NormSV650

        Super market Giant Eagle, based in Pittsburgh, sells gasoline under fuel perks program under the Get-go name. The fiancé gets the perks for buying mostly over priced groceries. Through data logging the ecu in her car after adjust the timing I always have yo ask what gasoline she has in the car this week as the Get-go does exercise the knock sensor more than other gasoline inbthr area.

      • 0 avatar
        White Shadow

        Unfortunately, that’s not an accurate statement. Most brand name fuels are not top tier.

    • 0 avatar
      tjh8402

      Not always the case. I track the mileage of every tank with an app and Costco gas has generally gotten fewer mpg than other top tier brands. I’d still take Costco over non top tier, but my butt dyno and my measured mpg say that in at least the last two cars I’ve owned (an e46 BMW and a Fiat 500 Abarth), Costco is not the preferred brand. Every car is different though. The BMW really liked Chevron. The Fiat seems to usually be happiest with BP and Shell.

      • 0 avatar
        windnsea00

        I have no evidence but I have always had the impression my current and past BMW’s ran better on Chevron and people I know who work on them for a living always felt that was the best brand. May mean nothing but I tend to stick to Chevron, on occasion I will go to 76.

        • 0 avatar
          tjh8402

          We do not have 76 here in Orlando. I sold the BMW over a year ago, but from what I remember, best, second best, and third best were all pretty clear as Chevron, Shell, and BP. Mobil and Costco were tied for worst, but again, these rankings are only relative to other Top Tier brands. I pretty much never put other brand gas in the car, and if I did, it was a partial tank to get me to the nearest viable top tier station. Same goes with the Abarth. I’ll put a gallon or half gallon in of off brand if I’m too close to empty for comfort.

        • 0 avatar
          JohnTaurus_3.0_AX4N

          Oh man, I miss 76.

          I used it all the time when living in Washington state. When I used ARCO (or worse, Valero in California), my mpg dropped and the car didn’t seem to have as much power.

          The most significant difference was when I spent a summer with friends in Placerville, Ca. On the morning I left, I filled up at Valero. At the time, I was in my 1992 Ford Tempo LX V-6 with about 170k on it. Normally, I got around 300 miles to a tank, sometimes closer to 350. In 187 miles since the Valero fill up, it was below a quarter tank. The SES light had come on several times, power was greatly reduced, and the idle was rough.

          I ran it down as low as I felt comfortable, then filled up at 76. No more SES light, ran smoothly, power was back, and I had 349 miles on the tank the next time I stopped for fuel (and it wasn’t even “on the red”).

          I could hardly believe what a difference quality fuel made. That car was never one to be overly-sensitive to fuel, unlike my 3.5L Chrysler Concorde, but it sure as hell didn’t like what Valero was serving.

          The Taurus John and I share now is getting high 20s/low 30s using Shell or Chevron exclusively. I think it needs an induction service, and I know it needs a new cap/rotor (which is coming, I’m just amazed the original still functions at 220K+!). The plugs/wires are new OEM.

          I have come to learn that quality ignition parts play a big role in mpg and power/smoothness. For my Fords, that means Motorcraft. I also use Motorcraft 5w30 oil and Motorcraft FL-400S oil filter. Yes, I know Ford didn’t actually manufacture the oil or filter, but their supplier is very good (Purolator makes the filters).

          Ive also used Motorcraft oil/filters on my Hondas, Isuzu Trooper, and even that [email protected]$tard Camry I had years ago. Thanks to eBay, I can get Motorcraft filters cheaper (with free shipping) than I can the cheap brands in the store (STP, etc). This includes the “odd” ones not intended to go on a Ford in the first place. I did use AC Delco filters on my Saturn, Oldsmobile and Isuzu Hombre (GM clone for those that don’t know), but stuck with Motorcraft oil.

          At 220k, the Taurus uses (burns? Leaks?) about a half quart of oil every 2500-3000 miles. Not bad IMO.

          The only cheap thing I’ll buy is an air filter. Everything else will be OEM or better.

          • 0 avatar
            anti121hero

            I have run Motorcraft fl1as (ford small block) filters in my jeeps for as long as I have owned them. Great quality filters at a good price. They really top of the line Purolators which are then specced higher by Ford. These filters Lso have the anti drain back valve which most others don’t, unless you get into stupid expensive Mobil 1 and k&n filters of questionable quality comparative of their higher price

          • 0 avatar
            joeaverage

            A friend claims that the local 76 stations are just rebrands BP stations that were suffering people perception problems after the Gulf spill. Same fuel. Different signs.

          • 0 avatar
            VoGo

            No. 76 is owned by Chevron.

    • 0 avatar
      energetik9

      I’ve always tried to use to use top tier, mostly on the advice of mechanics I knew, but couldn’t really quantify a direct benefit until recently. I personally use Shell exclusively now. Just anecdotal, I took my Porsche into the dealer recently for a minor item and was discussing an initial rough idle prior to warm up. He told me to try to use Shell and sure enough it went away quickly.

      Personally I could care less about price. A few cents from one retailer to another is not even worth the worry and the Shell near me isn’t more than a few cents difference +/-.

      • 0 avatar
        derekson

        I have found Shell to be the highest quality fuel as well.

        • 0 avatar
          joeaverage

          Our 300K daily driver has almost always used Shell and idles great and never pings.

          We bought a 150K mile used car from a friend who I think bought the cheap brands of fuel and it idled terribly.

          I did some maintenance like new plugs, replaced a couple of vacuum lines and idle improved. Once convinced it was mechanically sound we just drove it and used decent gasoline.

          We have been using Shell in the new (used) car for the past year and it’s idle is finally what I would describe as good. I know the EGR valve needed to be cleaned out (the passage ways carbon up and clog) but maybe not now b/c the idle has improved so much.

          As for the 5 cents difference between the economy fuel and brand name fuel – who cares. Anyone could save the difference by changing their spending in other categories. A nickel difference in fuel is what – 75 cents difference over a tank of fuel?

          We car pool, stay home, eat in, and keep our cars a long time. We’re saving plenty of money to afford fuel.

          Have never understood the obession with a few pennies at the pump when people have “expensive” habits in other parts of their life like smoking, alcohol or eating out alot. ;)

          I’ve heard stories all my life of people going out of their way to save a bit on gasoline and other things. Here – drive halfway across the county to use a coupon on a big bottle of aspirin. Or drive to the next town to save $10 on shoes. ;)

  • avatar
    pmirp1

    I wonder if there is a difference in gas quality/consistency between franchise brands like Chevron, BP, Exxon, Shell and the large retailers like QT and Costco. I always feel safer putting gas in from larger retailers like QT and Costco, whereas with the smaller franchise brands, I always wonder if quality depends on ownership and if they may dilute their gas quality at the franchise brand places.

    • 0 avatar
      highdesertcat

      The gasoline in most areas come from one or two refineries. In my area they are Artesia and El Paso,TX.

      Some of the gasoline from El Paso may have originated at the Pemex Refinery south of the border down Mexico way, since there exist an agreement to supply whatever the parties need, like American diesel for Mexico, and cheap 86-octane Pemex gas for the US.

      The Artesia gas is home-mined, home-refined, and delivered by truck, but has more sulfur in it.

      The El Paso fuels pipeline supplies everything else, like airports, military bases, a commercial tank farm, etc.

    • 0 avatar
      tjh8402

      I understand the concern. There’s a Chevron station very close to my house that, despite it’s brand, seems to always run not as well in my car. I usually see a 5-10% drop in fuel mileage whenever I have bought gas there and what I perceive to be a drop in power. Maybe the tanks are old and have contamination or have water leak in. Maybe the stations QC policy is poor (I know from working in aviation line service how important good QC is and what a difference regular and thorough checks can make even with a well maintained property). Whatever the reason, I no longer buy gas there.

  • avatar
    jmo

    You get what you pay for, film at 11.

  • avatar
    sirwired

    I wouldn’t necessarily go out of my way to buy “Top Tier” gas until they run the tests on a modern engine. I’m not sure how applicable the results from tests run on an engine 30-something years old are to a modern engine.

  • avatar
    highdesertcat

    Cheaper gas usually is the gasoline that was used to rinse a pipeline before the next batch of gasoline is sent through.

    Since the same pipelines carry diesel, jet fuel, AVGAS and other solvents, as well as gasoline at different times, the gasoline used for flushing is usually sold off at a steep discount.

    Techron, the Chevron additive, usually does a pretty fair job of keeping carbon buildup on valves down. I use one bottle per gas tank periodically, preferably when on a long driving trip.

  • avatar
    Rday

    I used Quik Tip top tier gas and I have had good results, in 2004 they were the only gas chain that advertised top tier and even went on to warranty their gas. Excellent company. In California and other areas while traveling i use Sam’s club. Dont know if it is tier one but probably not. they accept discover and that is what i like. Several stations in the Kc area have been having too much water in the gas so the brand is important. they need to close down these rip off artists.

    • 0 avatar
      pmirp1

      I completely agree. QT employees seem motivated, the stores are clean, service is quick, coffee is good. I really like spending my money here, I am positive they are treating and taking care of their employees well. A lot like Costco. Amazing what probably better pay and benefits do for moral of work force.

    • 0 avatar
      FlimFlamMan

      I agree. I always used Quick Trip premium in KC. Then we moved to L.A. for a couple years and had to deal with their crappy 91 blend out there. Now I’m in Georgia and was glad to see they have QT’s here with 93.

  • avatar
    Arthur Dailey

    Wasnt there an article about a year ago that you should only use Top Tier gasoline in EDI engines?

    • 0 avatar
      28-Cars-Later

      Added horsepower aside, it seems the GDI fuel injection system has a much tighter tolerance than its multiport predecessor. That’s really not what you want in a commuter.

      • 0 avatar
        gtemnykh

        Hyundai had it in their owners manual to either use Top Tier gas or else add a recommended Techron-type gas additive every 7.5k miles on their GDI motors.

      • 0 avatar
        davefromcalgary

        28,

        Speaking of commuters, they hyundai might be on its last legs.

        I’m drawn to this:

        http://www.kijiji.ca/v-view-details.html?requestSource=b&adId=1170666604

        • 0 avatar
          28-Cars-Later

          I would have thought you learned from the Verano to avoid one off GM :)

          • 0 avatar
            davefromcalgary

            Its just a Malibu in a nicer dress. 2.4 Ecotec, 4AT, all the same interior bits as my buddies Cobalt (stereo, switch gear), what could go wrong? Its a GM Saturn, not a quirky one off 90s Saturn.

          • 0 avatar
            28-Cars-Later

            You’d be better off with the quirky 90s one.

        • 0 avatar
          Compaq Deskpro

          No offense but I can’t imagine why you would want to buy that. Why not Impala?

          http://www.kijiji.ca/v-cars-trucks/calgary/2011-chevrolet-impala-ls-v6-59-bi-weekly-apply-now-drive-now/1153697216?enableSearchNavigationFlag=true

          Not sucking has to be worth another $2000.

          • 0 avatar
            davefromcalgary

            No offense take, just wondering why the Impala is considered that much better than the Malibu. I got no issues with the 2.4 and we don’t need that much space.

            I mean, I like W Impalas, but its her money and 5k is I feel enough budget to get a decent car.

          • 0 avatar
            28-Cars-Later

            Proven W and 60V6 vs then new Epi and I4.

            I don’t even know what I would do in your place, $5K CAD isn’t going to buy you much methinks. I opined on this yesterday:

            https://www.thetruthaboutcars.com/2016/07/barks-bites-buying-cheap-car-expensive/#comment-8032682

            https://www.thetruthaboutcars.com/2016/07/barks-bites-buying-cheap-car-expensive/#comment-8032418

          • 0 avatar
            davefromcalgary

            I should state that this car purchase would be cash, whether $3500 or $10000. You were mentioning notes in your messages yesterday.

            I skipped that column, because I know cheap cars can be a disaster, and one or two have been for me. But more have been excellent.

            The Hyundai actually still seems to have a lot of useful life, its just doing this thing were periodically it cranks like mad but wont fire. Previously, I’d clean the corroded terminals and it would be fine for another 6 months but now its doing it more. Battery and charging system check out. So I am thinking, some kind of loose ground? Which could pretty much kill the car because the diagnosis effort for something so finicky, on a car thats not long for this world anyways.

            Any ideas anyone on that issue? Bad ground?

            What is it with me and cars that wont start lately. I can deal with clunks and noises and sluggishness and all that crap. A car that MAY not start each time you turn the key is the very definition of unreliable!

            That Hyundai cost $2500 cash two and a half years ago. To date, we’ve done oil changes, front brakes, wipers and I had to do the CV axles cause the boots split, so I got remans and did them at my brothers. The tires were new when she bought it, and will outlast the car. Its been good to us and were in the clear on “what it owes us”. Its rusting pretty bad, and I’ve said that as soon as that goes through the rockers or is more than just surface rust on the frame/suspension, its gonzo. She takes no credit for this luck she had with the car, it just is. She was new to the country and needed a car, didn’t know much and thats what she bought. But, she’s thinking that “well, if I am going to spend cash and it might be unreliable, might as well make it less cash”. Call it 3k. Me, I think going up to 5k, you go from a 95 corolla with replaced body panels (accident?) to a 2008 Aura with 111k kms and a good engine (I like the Ecotecs.) To me, thats a good deal and worth the extra.

            For those not liking the Aura, I still think 5k is a good amount. Found an 07 Altima 2.5 for 5k. Vanilla 150k kms commuter. (I know, 9 year old Jatco CVT, its just an example of a newer vanilla midsize.)

            Because of what I’m seeing around 5k, and my own previous experience buying, and daily driving into the ground proudly 5k cars, I disagree about 5k being guaranteed disaster. My Alero was a 5k cash car, 6 years old when I bought it with about 140k kms. Drove it for for a solid 4 years and rolled 300k before the rust and an idiot shop killed the transmission (by undoing some recall work). The last year I threw a bit too much money into it, but it would have ran fine without all that nonsense, I just have a need to “fix things”, so while I personally decided to lose that particular money, the basic economics of the car were sound. As was the reliability and service I got out of it.

            THAT being said, I comfortably do most routine and even some complicated maintenance on my own, so that could play into why I am all over a 5k car.

            TL:DR I dont know what I am saying, someone please take my keyboard away.

    • 0 avatar
      davefromcalgary

      Both my mom’s former 07 Audi A4 with the 3.2, my brothers 04 GLI 1.8T recommended Shell or Petro Canada (and also recommended premium).

      The Verano can run on any grade of fuel, and GM also recommends top tier fuel. I use Shell most of the time, Petro if its more convenient. I run regular though for the most part. Have never really noticed any driveability issues, and the mileage doesn’t change significantly. I do like that GM has it tuned to take different grades.

      • 0 avatar
        Jagboi

        I had a car that would occasionally crank and not start and it was a flaky fuel pressure regulator. It occasionally stuck open and all the fuel returned to the tank.

  • avatar
    Land Ark

    They list Suncor, parent company of Sunoco, but not Sunoco. Does that mean Sunoco isn’t top tier?

  • avatar
    brettc

    Looks like in my area the only top tier brands that exist are Citgo and Mobil and those stations aren’t as common as the Irvings. I typically get diesel at Irving and the wife gets gas a lot at Cumberland Farms. I guess her car is doomed or something.

  • avatar
    Corollaman

    Costco has it but neither BJ’s nor Sam’s do, interesting! Surprised Valero is on the list as well.

  • avatar
    George B

    Is Top Tier gasoline beneficial for valve deposits for gasoline direct injection engines? My guess is that the better detergents might help the fuel injectors, but with direct injection the intake valves never see the detergent.

    • 0 avatar
      kincaid

      Everything I have read says George B is right. With direct injection which almost all new cars use, the gas never touches the underside of the valve head. This can be a problem since the crankcase vapors are introduced into the intake (PCV) and can burn onto the heads of the valves as they are ingested. Unfortunately since the intake is dry, the gas cannot clean the valve. Some manufacturers use a combination of port and direct injection which may help this issue.

      • 0 avatar
        mazdaman007

        SkyActiv GDI engines (and most hybrids) run a modified Atkinson cycle at partial load which delays intake valve closing causing some of the fuel/air mix to wash back over the intake valves providing cleaning benefits similar to the combined GDI/port injection systems.

        https://en.m.wikipedia.org/wiki/Atkinson_cycle

        • 0 avatar
          raph

          That’s interesting on the SkyActiv engines. Pretty neat trick. I wonder who else might be doing that to help with the deposit problem?

          • 0 avatar
            NickS

            @raph – variable valve timing, which is on most engines today, can permit a lot of neat tricks to reshape the compression and expansion ratios. You can re-ingest exhaust gases (a type of EGR), and re-expel intake back to the manifold (mixture pre-charge) which will then wash back over the open intake valves on the next intake stroke. There is also evap metering on the intake, but neither of these is as good as the port injected fuel washing over the open valves.

    • 0 avatar
      JD23

      You are correct. VW/Audi DI engines are especially susceptible to carbon build-up, making the manual cleaning of the intake valves an added maintenance task.

  • avatar
    dal20402

    I can’t think of a gas station in my area that isn’t one of the Top Tier brands, except for Safeway filling stations. The only stations within 2 miles of my house are Shell, Mobil, ARCO, and 76, all Top Tier. How common is non-Top Tier gas?

    • 0 avatar
      tjh8402

      it can be very common. 7-11, Sunoco, Speedway, Racetrack, Sams, Wal-Mart, Circle K, etc are all over Central Florida. BP and Mobil are usually the most common top tier stations. I noticed that it’s much harder to find in Lakeland, a town about an hour or so from Orlando. I have friends in Lakeland and I now make it a point of fueling up in Orlando before I head down there both becuase Top Tier is harder to find and tends to be more expensive when I get there.

    • 0 avatar
      slance66

      I have the opposite situation. In suburban Boston the only Top Tier brands I see are Shell and Mobil. Occasionally there is a BP. Sunoco, Hess, Irving, supermarket brands, Speedway, BJ’s wholesale (what we have instead of Costco), 7-11 and others.

      I always considered Sunoco, Hess and Irving as major brands. Irving sure touts its additives.

      • 0 avatar
        tjh8402

        @Slance66 – Irving may end up joining Top Tier. I remember Costco, BP, and Exxon/Mobil used to not be Top Tier. Costco began touting their additives and became Top Tier soon after. BP originally partnered with Ford separate from the Top Tier Consortium (I remember seeing Fords with “Ford recommends BP” on the fuel door or cap) and claimed to meet similar standards, but then eventually joined. ExxonMobil tried to be their typical arrogant selves for a while. I recall them saying they met the Top Tier standards but didn’t want to participate in the program because they didn’t want carmakers dictating to them how to produce gasoline. I chuckled when I saw they became a Top Tier brand.

        • 0 avatar
          thornmark

          Costco initially stated they met TT standards w/o joining the program. Seemed Costco didn’t want to add whatever TT association cost because of their slim margin on gas.

          And then they joined.

      • 0 avatar
        dal20402

        Come to think of it, when I lived in Boston, I almost always filled up at Hess.

        I guess for what we pay in Washington (third-highest gas prices in the country, and not all because of taxes) we ought to be pickier about additives.

  • avatar
    Sloomis

    Count me in as part of the 12%. I stopped using non-Top Tier gas years ago when (according to my trusted mechanic) the lack of detergents caused the fuel injectors in my 3.1 V6 Olds Cierra to clog up with some sort of crap, resulting in a $600 repair. Of course, he said it wasn’t entirely the fault of the gas, GM shared some of the blame for making engines with crappy quality, badly designed parts.

    • 0 avatar
      raph

      Seems like some anecdotal advice there? Did your mechanic say what crappy GM parts contributed to the injector failure?

      Now to be honest here I’m a Ford guy and no GM apologist so I’m not looking to right any wrongs. It just comes across odd to me when a mechanic says something like that.

      • 0 avatar
        Sloomis

        To tell the truth I don’t remember the details, this happened 13 or 14 years ago. Anecdotal or not, I took both statements to heart, I haven’t bought a GM product since either.

  • avatar
    indi500fan

    40 years ago (so this may not be true today) a Standard Oil chemist told me “everybody cheats on the additives but they don’t all cheat on the same stuff so rotate brands frequently.”

    GasBuddy (which I love) identifies Top Tier brands. Speedway – a big name in the Great Lakes area – isn’t TT.

  • avatar
    NoGoYo

    Not at all surprised to not see Wawa on the list, but unfortunately I’m stuck with it unless I want to go pay a lot more for Shell or buy equally suspect Turkey Hill gasoline.

    • 0 avatar
      NormSV650

      Ha! You close to my sister in S.E. PA.

      • 0 avatar
        NoGoYo

        More urban areas will have Sunoco, Mobil, and BP, but around here you get mostly Wawa. Hell, there are three Wawas in this one town thanks to a major state route (309) and the PA turnpike passing through it.

    • 0 avatar
      raph

      A buddy of mine used to work for Wawa – IIRC its part of their operating strategy to sell gasoline with the least amount of additive in it. From the way he was talking it wasn’t so much that they were looking to sell the cheapest fuel just that the company believed it was better to sell fuel that was more pure in that regard.

    • 0 avatar
      Steve Biro

      A friend of mine who drives to western Pennsylvania often fuels up at Turkey Hill stations when he’s put there. He asked at two different locations about who supplies their gas. Both times he was told it was Shell.

      Re: Wawa… it may not be top tier but since they pump so much of it, you know it’s fresh. It’s also clean. Wawa locations are almost pathological in keeping their tanks clean and replacing their pump filters often.

      It’s gettng harder and harder to find top tier brands near my home in central New Jersey. In addition to Wawa and QuickChek, there are a lot of mystery brands. Most top tier stations are a half hour from my home

  • avatar
    montecarl

    I always thought that the cheap gas stations were suspect…

  • avatar
    brn

    Your articles says 19 percent reduction in carbon deposits. The AAA articles says non-top tier causes 19 times more deposits. You may want to correct your article.

    However, please don’t correct it to the blurb or the infographic on the AAA site. They state 19 times cleaner, which is technically impossible. The person writing the article understood math, but those publishing it didn’t.

  • avatar
    65corvair

    I use Top Tier all the time. I read my owners manual and my Honda with direct injection said to use it. So I do.

  • avatar
    Paragon

    I switched to Top Tier about 2 years ago. I check Gas Buddy for prices and almost always use Shell gasoline now.

  • avatar
    meefer

    In SoCal I meet people who won’t even use Costco because “it’s the same gas that ARCO buys.” Luckily for me there’s a Costco gas less than a mile from my house. On my way to said Costco are a Shell, Chevron, 76, and Mobil. I couldn’t use non-Top Tier if I tried.

    Anyways I figure it’s like shampoo, keep mixing it up every once in a while. So I mostly go to Costco but throw in a tank of Shell or Chevron every once in a while. Haven’t noticed much difference in either of my cars between brands though.

  • avatar

    I recently traded my Ranger on a Honda Civic coupe. The Ranger had issues with a rough idle, so I decided to clean the throttle body. I had been using Cumberland Farms fuel because it was way cheaper than any other brand. I was shocked at the crud that had accumulated in the throttle body in just a little over 100k miles. It’s amazing that I hadn’t heard of top tier gas until I read the Civic owners manual. I’ve been using Shell and have found it is priced the same or only a few cents more per gallon that the most bargain brands in my area.

  • avatar
    ixim

    My 2013 I4 Equinox was notorious for accumulating crud on the intake valves, injectors and throttle body. Used not TT Sunoco as the cheapest name brand. No clue about TT. Over 10,000 miles, mpg, driveablity steadily declined. Two bottles of Techron improved things but did not solve the problem. New 2016 I4. Shell regular from day 1. At 5,000 miles, NO deterioration and steadily improving performance. Well worth the extra nickel a gallon.

  • avatar
    northeaster

    This seems like a perennially data-starved topic. Taking the AAA result at face value (which still may not be the right thing to do), I wonder if the polyamine ether that’s part of Techron is the only thing that much matters, though.

    I’ve been sufficiently compulsive to use a maintenance dose of it for years and can anecdotally claim success with Hess gas. But it’s really an uncontrolled experiment.

    • 0 avatar

      PEA does have an effect. Might be an interesting topic to explore in a future story.

      • 0 avatar
        dastanley

        I’m under the impression that PEA is the active agent that makes TT fuel Top Tier. The PEA is a surfectant that penetrates and breaks off minute pieces of carbon as well as coat metal parts to prevent new carbon from forming and sticking.

        I have read that Shell uses roughly one ounce of additive for every 16 gallons of Premium and uses 1 ounce per 24 gallons for the other two grades. I think the other TT brands use the same amount per grade but not sure how much.

        Personally I use either Shell or Conoco-Phillips in our two vehicles, one GDI and the other port injection. And besides, those stations in our town (both part of the Giant Convenience Store Chain) really stress customer service. So if I go inside to get a 44 ounce drink or nacho flavored Bugles, it’s nice to be smiled at and addressed as sir rather than treated indifferently or crappy at the local 7-2-11s.

  • avatar
    jcisne

    I wonder what the results would be with LPG. In most places it costs about 50% less than gasoline, and it’s supposed to run cleaner. LPG conversion kits are very common in Latin America, Europe and Asia.

    • 0 avatar
      dastanley

      Good question. Seems that LPG is popular with fleets such as municipal buses and local UPS delivery trucks, but that media attention for LPG has been pushed aside with all of the attention on gas/hybrid and electric cars. Probably more of a distribution/infrastructure issue than anything else.

  • avatar
    FThorn

    Next I’d like to see/know if using the equivalent of SEAFOAM would clean that intake sufficiently/noticeably.

    • 0 avatar

      I am not a Seafoam user but have used some other additives. I’ll add this to my list of topics to possibly explore in the future.

    • 0 avatar
      dastanley

      I’ve used Seafoam in the past, not pouring directly into the intake and smoking out the subdivision but using all of it in the gas tank and running it down to almost empty.

      Seafoam is made up of roughly three parts: 1) Distillates as the active cleaning agent/solvent, 2) Alcohol to absorb moisture (which with E10 is superfluous anymore), and 3) Kerosene as the inert carrier agent. Seafoam first came out I believe in 1940 or thereabouts so it’s somewhat of a throwback to older carbureted engines but can still work ok today. I was a little paranoid that using it would trip the CEL but that didn’t happen.

      On the other hand, using TT fuel at the local Shell or Conoco-Phillips should do the job just as well. And using a bottle of Techron once a year or so won’t hurt anything.

  • avatar
    LIKE TTAC.COM ON FACEBOOK

    There are other parameters to check for when comparing “Top Tier” fuel with the cheaper stuff. I would suggest A vs. B tests of fuel economy, horsepower, emissions, corrosion, tendency to vapor lock, and so on. What sort of substances do the “detergents” become when combusted? Are there more or less impurities and dirt in Top Tier gas? Is gasoline with more additives more or less carcinogenic than gasoline without? How significant is carbon build-up on valve stems to engine performance?

    How about doing a “weights and measures” test on octane – is the 91 really 91, is the 87 really 87, or is there some sloppiness going on?

  • avatar
    -Nate

    Interesting discussion .
    .
    I’m in California where we get really poor quality fuels due to local regulations .
    .
    In the last few years most ‘ gasoline ‘ we get , is yellow ~ never a good thing .
    .
    I’m old enough to remember good Gasoline being blue or if you were lucky , pink / red .
    .
    Sonoco blender pumps in the 1960s =8-) .
    .
    I don’t own any modern vehicles and I experimented with Top Tier 91 (only) octane fuels , all of them made my oldies run smoother and ping/knock / dieseling on really hot days , stopped .
    .
    Fuel economy improved slightly too as did easier starting and smoother idling cold or hot .
    .
    For many , that .15 cent price difference can ad up really fast .
    .
    Even Diesel fuel is beginning to be bad here ~ yellow like piss or beer if it’s from Chevron .
    .
    My Son thought ALL Diesel fuel is yellow , it shouldn’t be .
    .
    Techron is really good stuff if you can afford it , we used it int he City of L.A.’s fleet for decades , doesn’t take much .
    .
    -Nate
    Wondering why my comments always need to be Moderated ?

  • avatar
    Fonzy

    Shell V-power is always about a dollar more than 87 here in Ohio. Growing up it was always a $.10 difference between the octanes. Are we paying for the extra additives or marketing?

  • avatar
    montecarl

    In the twenty five years of owning cars I notice that sum were finicky about certain brands of fuel others not…I guess it must the design or tolerance in the engine..

  • avatar
    tankinbeans

    I use Kwik Trip (or Kwik Star depending on your location) and Holiday and haven’t been bitten. They both proclaim to be Top-Tier and are roughly the same in terms of price. I go the non-oxy premium route since my car recommends it and gives a second quoted power rating on premium. The funny part is that there are 2 KT stations with non-oxy premium within 2 miles of my house and the moleage is noticeably different between the them.

    At this point, aside from a few casino pumps, I can’t think of any stations that aren’t Top Tier in the southern Twin Cities, MN.

  • avatar
    Alfie

    Curious as to who paid for this ‘survey’.

  • avatar
    mchan1

    Funny how Gulf and Sunoco aren’t Top Tier but either’s gas is good.

    Costco’s gas may be Top Tier but may 2014 car’s engine drives more noisily every time after fill up while fuel efficiency was adequate.

    Switching out the gas on the next fill-up like Gulf/Sunoco/whatever brand made my car’s engine more quiet, perform more smoothly and fuel efficiency increased!

    Explains why I don’t frequent Costco’s gas station much anymore even for the few cents/gallon savings.

    Guess it depends on what additives are added into the gasoline by each manufacturer.

    But that doesn’t always justify the higher price.
    In my area (New England), Mobil has ALWAYS cost more like ~$.25/gallon MORE than other [leading] brands of gasoline.
    What a rip-off!


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