Just looking for opinions.

I have always used Exxon/Mobile or Shell (when I can find) Super Unleaded in my Vettes. I always thought they were the 2 best.

Well, a Costco opened up the road from me, and, being a member, checked out their gas prices. They are $0.30 a gallon less exppensive on Super Unleaded 93 Octane compared to all the stations around here.

Is the Costco gas of a good quality?

I would love to save the bit of $$$ on the gas.

 

Does it advertise any additives? That may be a new come on price. The no name no additive stuff is either the same price as Chevron/Shell around here or just a couple cents less. I rarely use no name no addditive fuel in any of my vehicles. I do once in a while but will drive across the road for a top tier fuel.

 

I love Costco, but their gas is crap. I also was alured by the cheaper price so I gave it a try in my DD. Ran like poo for the next 200 miles with plenty of knocking. Never again. Glad I did not fill the vette!!

 

Lots of debate on the issue, however there appears to be good reason to stay with one of the TOP TIER rated brands of gasoline, which I believe Mobil and Shell are considered.

For added protection, I pour Amsoil PI into the fuel tank on my vehicles every 4,000 miles.

Regards,

GSRANDY

 

Most gasoline is formulated the same. The only difference between brands is the additive package. That's a pretty substantial savings with the Costco brand. I think if you were to supplement the Costco gasoline with an occasional bottle of Techron you will be fine.

 

As long as it's 93 octane you should be fine. You can be a little pickier if you let the gas sit for a while. If you can, try gas without ethenol if you can find it.

 

You can google "TOP TIER GASOLINE" and get the current list, which changes occasionally.

Some people claim it's all a marketing/liscensing scam, others say it's a real benefit. I'm inclined to think there is a benefit.
Since nearly all of the major brands are now on the list, I use them.

A petroleum engineer said that to be really good it it, try to use one top tier brand for 2,000-5,000 miles, then switch to another for 2k-5k, then switch to a third, then back to the original. Keeps the additives removing different types of deposits, even though they are minor.

If I drive 10,000 miles per year at an average of 20 mpg, and top tier gas costs me 3 cents/gallon more, that works out to $15/year. I can handle that.

 

Several things come into play here. The majors usually have better detergent additive packages, and what I use. Costco may have some advantages moving lot's of fuel, keeping things fresh. They maybe even lose money on the deal getting you into the store to buy more stuff. Not a big shopper myself, so usually just go to the corner Mobil station.

 

Mobil is not TT gas, Shell is. I'm sure your Vette will find little differences. I use Shell but find it overpriced. Use to get 5% off per Gal. but that went away this month after 6 years.

I take it back Exon /Mobil is now on the list. Thats good news .

 

I've always used Chevron with Techron in all my cars. Never had any problems with the way they run.

 

Both Chevron and Texaco have the coveted Techron in their gas - keep those injectors clean.....

 

Very good advice from Gearhead Jim. Follow the bold section as a best practice.

 

Storage conditions at the station can be a much bigger factor than the gasoline itself. Pumping top-tier gas into 20 year old tanks at the station is going to add all kinds of contaminants. Look for stations that are relatively new and do enough volume to keep the gas in the storage tanks fresh.

 

Those are my feelings as well. . .

 

FYI, if you have or get a Costco no-fee AmEx card (doubles as your Costco membership card) you will get an additional 3% rebate on your Costco gas purchases which probably amounts to another ten cents or more per gallon.

That said, 30 cents is a pretty large spread even for Costco. Fifteen to twenty cents is more common (before the 3% rebate).

 

There are two types of differences between the various places you can get gas. The additive packages will always vary from brand to brand no matter where you are in the country. The basic source of the gas may or may not vary, depending on where you live. First, the additives. Various brands of gas all have their own additive packages to prevent deposits in injectors, valves, and manifolds. Gas you get at grocery stores, Costco, Wal-Mart, etc, will have a generic additive package that meets minimum standards, but it will not be as good as branded gas. Of the gas company brands, those meeting the top tier standards will be the best. So you have three groups, gas company brands that are top tier, gas company brands that are not top tier, and the grocery store types. You are not likely to notice a difference within a few tanks, but you will over the long haul. Once you get to top tier, differences are very small. Chevron has done the best job of marketing by calling theirs Techron for a long time, but just like all the other brands’ additive packages, the composition of Techron has evolved over time. So while it is just as good as the other top tier brands, it is no better. To be top tier, you must demonstrate ultra low deposits in all areas of the engine in actual engine testing.

As far as the source of the basic gasoline before the additives are put in, some parts of the country are served by common pipelines with exchange agreements, so you can’t tell whose refinery the basic gas came from. In those areas, other than the additive packages, it’s the same basic stuff whether you buy top tier, other gas company brand, or grocery store brand. In other areas of the country, the big gas companies have direct links to their refineries, while the grocery store brands buy from whoever happens to be cheapest at the moment, including imports. In those cases, there are more quality control risks to the grocery store types. If you live on a big river or the ocean or near a big refining center like Houston, LA, or Chicago, you are more likely to be in the group where majors are tied specifically to their own refineries, and grocery store brands get whatever is cheapest.

 

Yep.

From Houston, are you in the oil business?

I worked many years in computing for a major oil company. Supported all areas of the company. Learned some about the 'exchange' business used for gasoline. Basically, you have no idea where the base gas comes from. In any area, most of the gas will probably come from the same terminal, a tank storage facility on or near a refined products pipeline. When a truck tanker loads, the additives are added as the gas is loaded, and the various retail outlets getting the load specify their additive 'package'. So, the base gas is all the same. Only the 'package' differs. And there are federal regs that determine the 'minimun' cleaner additives that must be in all gasolines. This minimun is at a level to keep injectors clean. Federal regs came about because years ago when injected motors first came on the general market, there were lots of problems with clogged injectors from gas deposits. So, they set the min regs for cleaner.

Also, there are major areas of the country where your local government has passed all kinds of laws about emissions. The base gas in these area has to be at a certain level and the additives have to struggle to meet these emission levels. Which may be impacting the drivablility of your car. And these emissions regs differ across the year. Butane, propane, ethane, all kinds of stuff is in your gas to help starting in cold weather. And your local regs, set by people who have little if any scientific knowledge about fuel and motors, have set these regs.

The big, plastic sign out front on service stations means very little any more. The company I worked for has owned ZERO service stations for several years, and even before that, it only owned a few. Even if a station is 'branded', the companies take little control of what goes on at that station. Many branded stations are owned by local 'distributors' than own multiple stations in an area, with many also owning the tanker trucks moving gas from a terminal to their station. And who knows what additive package they are putting into their gas. The company owning the 'sign' will have specifications for the additives, but do you think they go around and pull gas samples and analyse it?

Do people want to hear about how one refined product pipeline moves all kinds of different product? Gasoline, diesel, kerosene, jet fuel, heating oil, etc, etc goes down one pipe???? And they separate the different products with a big 'slug' of WATER!

Oh, you didn't want to hear about that???

I just love the topics about 'What's the best gas.' 'I only buy xxxxxx brand gasoline.' 'Which is better, xxxxxx or yyyyyy gas?'

 

Screw the injectors.. keep the fuel level sensors clean and sulfur free!

(then again, you can add a bottle of Techron once a month like I do)

 

I'm not a fuel expert, and I don't play one on TV. However, my brother drives a fuel tanker and based on our conversations, this is what I follow for the Corvette:

• only buy TT
• won't buy at local convenience store
• Ok at Costco, not all the time

 

the same gas truck goes from one station to the next one.