https://consumerist.com/2010/05/14/costco-dispenses-e85-ethanol-instead-of-gas/
Here is the news article on the lawsuit of problems with the gas at one station. It’s unclear what the problem was.
I don’t know @m0minmd. But thanks for sharing. They did transition from " clean power" or something like that to " Kirkland Signature" gas whatever that means…
@gunnerz thanks for sharing your issues.
This is just one station, an isolated incident. It was not like Costco was trying to sell ethanol with a tiny bit of gas intentionally. BTW, I have never heard ethanol referred to as “corn juice.”
I do not think we can venture into the ethanol mandate issues without this thread quickly turning political…
I do not belong to Costco but i see long lines waiting at their gas stations. Is the price difference really that large? Is it really worth it to these people to wait 15 minutes to save 2 cents a gallon? Or is it a significant savings?
Here the savings is usually 15 - 20 cents a gallon. Worth it to me. But I go when I know the lines are shorter.
The difference has been as much as 30 cents per gallon but right now is 17 cents.
My S4 runs just fine on premium Costco gas. If they’re adding stuff on site, it’s being done underground; I’m often in line when the trucks deliver/offload.
It’s easily 50 cents less than the nearby chevron station.
Wow, I guess it is worth it 
It’s worth it to us! We do fine with the lines at Sam’s and Costco- never that bad.
I don’t know the answer to your question but can say we fill up with their gass all of the time and have had no issues. We do not use the premium but just the lowest grade.
Plus, if you use your Costco Visa, you will get 4% cashback on your Costco gas purchases. That’s another 8 cents or so per gallon right there.
There’s a Costco on the corner of my freeway exit, so my car rarely gets anything else. Pretty sure I can pay my membership fee out of the gas savings. Love it! There are lines, but most people don’t understand that the hoses are so long that you can use the right-side pumps on left-side has tanks, so I pull right in. Sshh! Don’t tell!!!
All gas comes from the same refineries, only the additives are different.
The winter blend/summer blend refers to so called Oxygenated gasoline, in winter it has it, in summer it doesn’t (it actually was the topic of one of the puzzlers on the old “Car Talk” show on NPR, wish that was around, would be fun to send them a question like this one. My opinion, if your husband really believes that Costco gas must be bad, it may not be worth the battle, but as a semi retired gearhead I really doubt using Costco gas would shorten the life of the engine, unless the local dealer had tanks full of sludge or something like that, if they didn’t get them cleaned properly or they were buying crappy gas, which I doubt. As far as special additives go, I am pretty dubious about that, most of those claims are marketing claims more than reality (I do know, from reading something SAE put out, that a lot of the ‘studies’ they claim prove their gas is better, are like the ‘clinical studies’ that show a weight loss pill works, they are small samples and of dubious quality:), the way modern engines are made, with the engine management computers and fuel injection and HEI ignition, for normal driving it won’t make much difference what gasoline you use IMO.