RyanC7

You do realize gas brands all all based on additives right? Gasoline is gasoline. The brand or octane is mixed at the terminal when the truck is filled. I used to program the controllers at the terminal (they were made by hyrolec) and the driver would select his product and it would be mixed on demand and pumped into his truck.

quick read on the process...

http://blogs.platts.com/2010/08/23/unbranded_vs_br/

Oh and just because it says Exxon on the station the "Gas" could be generic....they were only "required" to seel so much "exxon" to have a station. This was back in the late 90s so things may have changed...who knows.

JK 23112

Gasoline is gasoline and there are so many "blends" that are required by the EPA in just about every area/district/market. The 'top tier' designation has to do with additives.

From what I understand, the additives are mixed in at the distribution point (when the tanker is filled before going to the retailer) OR dumped in at the gas station when the fuel is delivered.

I would assume that you can SOMETIMES end up getting top-tier fuel at an off-brand station......but you are supposed to be guaranteed to get it at a branded station that meets the requirements to be part of the network.

With a run of the mill car, I suppose the top-tier fuel will not matter much.......but with a Corvette, I guess it is best to pony up a few more cents to be assured of getting the good stuff.

Maxpowers

The one by my house can be a 20 min wait.

Elvira15

The best thing about Costco gas is it doesn’t sit in the tanks. They sell such high volume that it’s always fresh. That’s why they don’t have any windshield cleaning materials or liquid—they want people to fill up and get out. Unless I’m traveling, I only put Costco gas in my cars.

NOMOREWORK

Another Costco user here, best time to go is early on Saturday morning at the store near me.

JerryU

Interesting, Sunoco does not have a sign saying Top Tier at the pump (at least around here,) but as you note, says it is with all their own marketing hype info on their website.

I use Shell who also doesn't have anything saying Top Tier except on their website! However their prices at the lowest price Shell station for 93 octane, which all have for hi test in SC, is usually ~0.40/gallon higher than Sams Club. (My last fill was at Shell for $2.93/gallon versus Sam's Club that was only $2.52! I keep a spread sheet with mileage and purchase price difference!) We don’t have a Costco in town so I fill up about 1/3 of the time with Sams Club hi test, which is 93 octane. One advantage of living in a smaller town is they have 12 pumps and I seldom wait and pull directly in and pump, Most gasoline comes to our area via pipeline so probably the same base gas others have BUT without the additive package put in the tank truck when it is filled to make it Top Tier.

For that reason and to help avoid possible sulfur build-up on the gas gauge sender as well as provide some injector cleaning I added a container of GM recommended gas additive at every oil change of my 2014 C7, as they suggest if not using Top Tier. Having checked the SDS sheets I will use Techron for the Grand Sport as it appears to be the same “stuff” probably packaged for GM. Was buying the GM product from Amazon but GM has confounded the situation and it appears now sells their labeled product only through GM Dealers.

FWIW, sulfur is in all crude oil, as much as ~3% in sour crude, that is hopefully removed when refined to a low spec level. Sulfur content in gasoline has nothing to do with Top Tier, which is strictly an additive package. GM and Techron product info say they dissolve sulfur and mention fuel senders. There have been a number of posts on the subject. To replace the sender the rear drive train has to be dropped to remove the gas tanks! One poster was horrified when he saw his car apart. Another poster said a dealer solved his erratic fuel gauge reading by installing two bottles of the GM fuel additive and charged him $100. Probably was out of warranty as a dealer may elect to take the Vette apart and replace the sender as they would get paid much more from GM than putting in a container of fuel additive!

torchredz51

Costco is the only gasoline that I know of that actually uses a C7 in advertising their gas. Clearly they believe that their gas is just fine in a C7.

Patman

^^^ I like that they used my car in their advertising Seriously though, it's interesting how they show a picture of a C7 and mention that it protects intake valves. With the direction injection on our cars there is no fuel washing on the backside of the intake valves, so they cannot be cleaned via gasoline or gasoline additives.

Patman

I went to Costco at 9:30 this morning (this time with the C7, last night was in my daily driver) and only had to wait about a minute to get a pump. I saved almost $8 on that half tank of fuel added.

Rebel Yell

It doesn't have anything to do with being young my friend. I'm old, and I won't wait very long for anything. It's like a genetic defect that will stay with you forever.

BTW, I wish we had a Costco near my house so I could just try.

KCV

LimaCharlie

I use Costco gas. I stopped for gas one afternoon this week and drove right up to the pump. No line, no waiting.

GoatHead

For what it is worth, using 87 octane, Costco is the worst gas for my commuter Honda. When I bought the car new, I tested and calculated several full tanks from different brands. Costco was the worst for gas mileages.

Bob Paris

My sentiments exactly

Bob Paris

The truck that delivers to Costco probably heads next to a name brand station. It is all about the additives and top-tier fuels are essentially the same regardless of where purchased

Patman

It really shouldn't be any different than any other 87 octane out there unless it contains a higher level of ethanol compared to the others.

In the case of Costco in Canada, we are lucky that the premium sold there is ethanol free. Same with Shell V Power here as well. So when I use either of those premiums I see better MPG compared to the stations here that use 10% ethanol.

Also, my daily driver is a Honda Civic and I get the same MPG with Costco 87 (which has 10% ethanol) as I do with any of the other 87 octanes here (all of which have 10% ethanol). BTW, I have a fully calibrated Scangauge II in that car so I am constantly checking the MPG on every trip I take with it.

GTFD2

I use Costco as often as I can. Not only get the reduced price but I use my Costco Visa and get another 4% discount. That's another .08 plus.

Spice red Ed

Same here, Pumps open at 5:30am and until about 9am you never have to wait. Long lines after the store opens at 10am.

Gonzo

That's what I use

383vett

Used it for years in all my Vettes.