Costco opened a store near my home and I have recently joined.
I am looking for information on the make up of their gasoline. It seems to be a great deal.
I cannot find how much ethanol they add to the gas. This is designated by E10, E15 or E85.
I also see that they are designated as carrying Top Tier gasoline. Which means the gas has more detergent in the gas than the EPA requires. Costco states they have 5x more detergent than the EPA requires. I do not know how much detergent is added to be in Top Tier and if Costco adds even more than Top Tier gas requires.
I also have read that Costco blends these additives on site which leads me to believe there is a greater chance that the gasoline may not always be mixed properly. I do not know if a machine does this automatically or if an employee does this on their shift with little crosschecking.
I did find one lawsuit that claimed Costco has ruined numerous cars by having the mix wrong. They apparently agreed to fix those cars and agreed the damage was from the gas. They were accused of having E85 pumped into the cars which they denied.
So have you had an issue with Costco gas? Do you know how much ethanol is added? Detergent?
That’s not something I track/care about TBH. I just know that Costco is cheaper than other gas stations consistently. And don’t seem to jump/react in price as quick/high as other gas stations.
“…A: The federal Energy Policy Act of 2005 established the Renewable Fuels Standard, which required that a certain amount of ethanol be used in the nations’ fuel supply. The Energy Independence and Security Act of 2007 increased this amount. Kirkland Signature™ Gasoline complies with this law, and if our fuel contains ethanol a pump decal will advise you of that fact.”
Sax, what kind of car are we talking about? Why are you so concerned?Is this a Maserati or the like? My anecdotal experience - 3 plain vanilla Toyota and Lexus cars have been fed Costco gas almost exclusively for the past 15 years, and every single one of them is still alive. None requires premium gas, just regular.
If you really are that concerned about gas quality, get a Tesla.
We use Costco gas almost exclusively for both of our cars here in California. My 2014 Acura RDX requires premium. In our area of Southern California the Costco gas is the lowest price in the neighborhood. We have never had any issues with their gas.
The guidelines that Costco sites does not jump the ethanol to 15%, it has money to fund studies about possibly requiring more than 10% in gasoline, seeing the impact and such, but does not require it. One of the rules is that if you are a gas station franchisee they franchiser cannot have in their agreement limitations on alternative fuels, like selling E85 or biodiesel (like B20, 20% bio diesel, 80% from crude), and there is other funding for things like an ethanol pipeline. There are cars that can run up to 85% ethanol, the biggest challenge with that is alcohol eats away at some type of seals and gaskets, and also because it is hydrophillic can lead to standard fuel lines corroding and other problems, the car computer can adjust to the different burn characteristics of alcohol. I wouldn’t worry about it, the costco gas I have seen is 10% ethanol, same as other stations.
As far as detergents go, the amount of detergent is determined by the person doing the blending. I wonder if costco blends their own gasoline, or buys it from independent suppliers (which would be one of the reasons it is cheaper, franchise stations pay the rate their overall company decides), I would think the latter, a lot of the claims about detergency and nitrogenated gasoline, according to a couple of friends of mine who belong to SAE, is more marketing hype than anything else,most gasolines have detergent levels in them that are very similar, and they claim that there are no studies showing significant difference between gasoline blends. Thing about costco IME is they tend to pump a lot of gasoline, so it doesn’t sit, gas stations where they don’t pump a lot (for example, the franchise stations with the expensive gasoline prices, they do that because they want to be a franchisee and get the benefits, but want to concentrate on repairs, not gasoline) can end up with gasoline that has water in it and whatnot from sitting, stations where it turns over rapidly don’t have that problem.
I have used Costco gas, including older cars that can be finicky, and never had any problems with it, there were national brands in the old days I wouldn’t use because their gas was crappy.
@bunsenburner:
Even if they were in a maserati or ferrari, wouldn’t matter much. With premium gas, some stations sell gas with an octane rating of 94 or so Pump Octane number (the US uses a different standard than overseas, in Europe they use RON which will be higher, there also is something called motor octane number, which will be lower than you see on the pump, pump octane is an average of the RON and MON numbers), some their top end premium is 92 or 93 (I think costco does go to 93). You can run lower octane in modern engines, unlike the old days before engine management systems where you had to worry about knocking, modern engines when it senses lower octane fuel automatically retards the ignition and changes the air/fuel mix to compensate, you lose power in an engine that requires premium, but would not cause damage (and given the power of many cars that require premium, the horsepower they can put out, I wonder if people would even notice if they used lower octane fuel in daily driving).
I mentioned this because unless one has the means and likes to change cars like gloves, it would matter when it comes to repairs - premium cars cost a bundle of $$$ to repair. Most people who get their dream car want it to last as long as possible. Naturally, such a premium car owner would be concerned that something in the gas might ruin the non-metal parts before their time.
The reason one might care is that ethanol is not all that great for your car. It reduces MPH and gets “old” pretty quickly. Its also really bad for small engines.
Now apparently only 5 states mandate ethanol be added to gas which was shocking to me as I thought all along it was a federal law. However most states add some ethanol. I don’t mind some in my gas but I want to make sure Costco isn’t cheaper because they add more ethanol.
Interesting, I thought the ethanol mandate for the 10% was federal, it is state law. However, I kind of suspect with ethanol that it is much like the pollution laws, where they used to have 49 state cars and then cars done specifically for the CARB requirements, these days cars are 50 state models (in part because regs became close enough that it didn’t pay to do it). I suspect most gasoline these days has ethanol in it, simply because it is a lot easier to blend it en mass then try and tailor it for individual states, the report I read said you are likely to find ethanol in most gasoline sold, unless they specifically have a sign saying it is ethanol-free . http://www.greencarreports.com/news/1099149_state-laws-on-ethanol-in-gasoline-only-seven-states-require-e10-blend
As far as the quality of gasoline goes, one of the things to keep in mind is that there aren’t that many refineries in this country, so the gasoline you buy is likely not all that different no matter where you go. The independent stations are buying pretty much the same gasoline that the guy at the Shell station is, the only difference is the independent is kind of like those cut rate phone plans, they are buying gasoline on the spot market from independents (which name stations use as well I might add, they are allowed to, if the name refiner doesn’t have the capacity to supply them, but they are not allowed to undercut the sale price, they have to charge what they would if they bought it from the name supplier), so it is unlikely that quality of gasoline varies that much (in terms of an exotic car). As far as ethanol goes, most car manufacturers these days factor that in in building cars, so I doubt that would be an issue (though if I owned a 500k supercar I would worry about it, even knowing what I know).
The whole ethanol thing to me is a scam, it was originally designed to cut down reliance on foreign oil supplies (ie the shocks in the 1970’s), but it is not environmentally friendly per se (refining ethanol is energy intensive and also due to the way they make it, is generating more greenhouse gases then it supposedly saves), and it has other issues, alcohol burned like that can cause other kinds of pollutants to form, like formaldehyde. Ethanol is only economically viable because of huge tax subsidies (without it, even the 10% mix would cause the price of gasoline to soar) and basically is a giant government subsidized perk to the corn state lobby and the agribusinesses like ADM and Archer Midland, and given that the US now has enough oil capacity to meet its own needs, it doesn’t make sense economically or environmentally, it is good old pork barell politics at its best (or worst).
Yes, I had problems pumping Costco regular grade gas into my SUV. A new Costco opened nearby a year or so ago. I filled my SUV’s tank with Costco regular. A day or so after the yellow check engine light came on. I thought maybe it was just a bad tank of gas. I went back to Costco a second time when I needed gas and the same thing happened. I eventually used the tank to near empty and the next time went back to my usual big-name brand of gas. The light went off and no problems. I haven’t put Costco gas in my SUV ever again.
^^Do you know that if your gas tank cap is not tight enough, the “check engine” light can come up? Your experience with Costco gas could be a pure coincidence.
Sax- there are 2 issues here: % of ethanol and additives. My point addressed the former.
@BunsenBurner . Yes, thanks for clarifying that. The ethanol in Pa. should be 10% and no more ( i think). Same all around?
The " detergent" additives would be added at the site
Seriously, my H is very particular about his new ride and I really want him to use the Costco station which with the credit card can be as much as 20 cents a gallon cheaper.
Ok, let’s put it this way: so Costco adds a tiny amount of an additive to the same gas other stations are getting. Other stations add their additives. It does not equal dilution of gas.
For the sake of your marital peace, I think you should forego the savings and let your H take his car elsewhere.
Costco’s gas is less expensive not because it is more diluted, it is less expensive because it marked up less.
This thread made me think of something. I recall from past years that Costco would post a sign that they were transitioning from the winter blend to a summer blend and then sometime in the fall that they were transitioning to the winter blend. I thought it was federally mandated. As a regular costco gas customer, I don’t recall seeing notifications for at least a year. Did rules change?
