Costco gas...exaggerated savings?

[BoilermakerZ519]

I have used Costco gas off and on and think I’m done with it. All of my experience w four cars shows that I get a 5-8% drop in gas mileage.

The straight on price savings is typically 7%.

Everyone says it’s the same gas as other stations, in fact, better than some as it carries the “top tier” stamp of approval.

Whether it’s the gas, the way they store it or whatever, my experience with enough data points shows I am saving little to any money so waiting or managing my route to fill up at Costco is just not worth it.

File this under “there truly is no free lunch” for me. Whose experience is the same or different?

[The Bass Junkie]

I have used Costco gas off and on and think I’m done with it. All of my experience w four cars shows that I get a 5-8% drop in gas mileage.

The straight on price savings is typically 7%.

Everyone says it’s the same gas as other stations, in fact, better than some as it carries the “top tier” stamp of approval.

Whether it’s the gas, the way they store it or whatever, my experience with enough data points shows I am saving little to any money so waiting or managing my route to fill up at Costco is just not worth it.

File this under “there truly is no free lunch” for me. Whose experience is the same or different?

Costco Gas is $0.50-0.75 cheaper here on average....when we are in texas its the same as HEB or Wal-mart...except people still get in line for it. All hawaii gas originates in one place so the only difference is additives. I don't sit down to try to figure where I get better mileage from...we burn 100-150 gal a week in fuel, it really never deviates how often I fill up regardless of where I buy gas.

[jarhead175]

Have 2 stations here I have noticed the issue. Figured they were putting the E85 in all the tanks. My ford is a flex fuel but mpg goes to crap on ethanol.

[Bassin Bob71]

My wife works near a Costco and fills up there often. She has no data to back it up but has said she doesn't get as good as mileage with Costco as she does with BP. I think she might be right as we took it for an early family Christmas yesterday on a 5 hour round trip and with me driving (I always get better mileage driving her car then she does) I thought the mileage was a couple mpg worse than it should be.

[Bryanmc57]

Have 2 stations here I have noticed the issue. Figured they were putting the E85 in all the tanks. My ford is a flex fuel but mpg goes to crap on ethanol.

If the sticker on the pump doesn't say it's E-85 (or up to 15% ethanol) they're breaking the law.

[wildturkey]

Interesting. I wonder if they do increase ethanol to offset the price. I have purchased there one time so I can’t say if I got lower mpg.

[Bassman Ia.]

Have 2 stations here I have noticed the issue. Figured they were putting the E85 in all the tanks. My ford is a flex fuel but mpg goes to crap on ethanol.

Yea, I’m sure they are adding more ethanol . They are probably banking the extra savings so they can pay a huge lawsuit when they get caught.

[gehol]

If the sticker on the pump doesn't say it's E-85 (or up to 15% ethanol) they're breaking the law.

Very odd math

[davidsa]

I use costco gas in the Kentucky area and Ohio regularly but not every time for 20 years. I see no difference in miles per gallon. Sourcing can be different depending on where you live i guess.

[Jfish]

I have a friend that swears Sams Club gas is sub par also, I rarely use it and have never checked it, as I try to give an actual garage/gas station my business since they provide free air and fresh windshield cleaner.

[getfished]

Ithink if the octane rating is the same the mileage will be the same regardless of the price.

[Steven H]

I 100% got bad gas from one by an old job about 10 years ago.

[DrewFlu33]

If this is true, I think one thing that probably happens is their E-10 actually has 10% ethanol in it. I've read a lot about people testing gasoline in other places that have significantly less than 10% ethanol. I'm not super knowledgeable about refining processes, but I also know that ethanol is an octane booster, so I'm guessing they can start with "lower" quality gasoline before raising the octane with that ethanol as well.

For what it's worth, I've seen the same trucks deliver gas to a BP station and my local Sam's Club, so I've got a pretty high degree of confidence that they're getting the same thing. Stuff is different everywhere though.

[DURASPANK]

Check the ethanol content. Not hard to do a water test. Bet you'll find a higher content in one vs the other.

[Jeff La]

ON the trucks I drive I keep a log of every fill up. I list station amount, and mileage. I have proven time and again Wal Mart (Murphy) gas does not get as good of mileage as other branded stations. I periodically check my Tahoe mileage and the same is true for it. For the last two trucks I've driven diesel and see no mileage difference in Wal Mart or other stations.

[n2ratfishin]

Buy a Tundra and you'll never notice a difference.

[jarhead175]

Yea, I’m sure they are adding more ethanol . They are probably banking the extra savings so they can pay a huge lawsuit when they get caught.

I'm not saying they are adding ethanol I think they put E85 in the wrong tanks to make more money. My truck averages 16-17mpg if I fill up at either of those two it drops to 14mpg. Which just happens to be the mpg I get on E85. And I have only had that issue at those two locations. Both are small privately owned stations so it wouldn't surprise me at all.

[gehol]

I'm not saying they are adding ethanol I think they put E85 in the wrong tanks to make more money. My truck averages 16-17mpg if I fill up at either of those two it drops to 14mpg. Which just happens to be the mpg I get on E85. And I have only had that issue at those two locations.

Really, think of the liability of E85 being put in a non flex fuel vehicle due to mis labeling.

[RazorCat]

The pumps say “Up To 10% Ethanol” meaning anything from 0% to 10%. Maybe the Costco gas you’re referring to is full 10% ethanol, but I highly doubt a chain like Costco would risk the liability of putting E85 in a pump labeled otherwise.

[donpilot]

In the Louisville area we have several brands. All of them come out of a marathon pipe.