Maybe so, but 20 hears ago my Saab 900 kept dying at stop lights. At the time I was using the cheapest mid-grade gasoline I could find. I mentioned my issue to the local Texaco owner and he suggested I start using "name brand" fuel. I bit the bullet and started paying the extra 2 or 3 cents per gallon and the issue went away.

 

Driving long trips I do see a 30 or so mile increase in fuel economy per tank while using Shell premium in my XF. Never had any issues with Sam’s club fuel. I will still hunt down a Shell or Mobil station before anything else. Call it good marketing, superstition, or personal experience.

 

Costco gas is nothing more than a marketing brand. It comes from regional refineries through wholesalers. Half the fuel in your town could be coming from that refinery being sold under various names. I often buy premium at Costco, you should have no problem. Related to that, every year I take the ‘99 XK8 on a little jaunt of 1,200 miles from Washington the Southern California. This is no doubt ridiculous for sure but I’m a creature of habits. In the weeks before heading south I run the tank to almost zero. In town is a fuel station that has pure gas with no ethanol. It’s a bit more than the premium with 10% ethanol. I fill it to the top while giving myself a dose of the myth that this good for the engine. (Reality: the Jag engine is designed to use fuel with ethanol) But since when does the owner of a 20 year old Jaguar always stick to reality? Yes, I do get maybe 2 more miles to the gallon but that nowhere pays for the extra cost. With that full tank I can get from my home in Western Washington to Ashland Oregon which is a few miles from the California border. Spending the night in Ashland, the next morning I drive to the southern most I-5 entry of the community where there is an ARCO station that always has the lowest prices in the community. There I fill up and its enough to take me to Stockton, California where I spend the next night. I have done this exactly the same way for the past 5 years. And, that’s the only time the XK8 gets a dose of ethanol free fuel. You would think I might have other things to better occupy my time. It’s a Jag Thing.

 

Sounds a bit like the RDAs given for human health. The RDA is what you need to avoid being sick, but it's far from optimum for good health. So I guess it's the same with gas -you can use the lowest common denominator fuel, of you can choose the one(s) which have additional additives that are more optimal for the well being of your vehicle.

 

Also new at costco, and with the 6% discount on gas....it beats anything on the street. 4% from costco and 2% more from using the costco CC.
I filled my 98 Jag with 91 oct. NO PROBLEMS

 

Not much if any line here, but then again, I get the gas and shop at 9am. Best time for less crowds at store. Also in Ca most stations charge .10 more if you pay with CC, not Costco.

 

The long lines are for people with fuel inlets on the left side of the car. Your fuel inlet is on the right side. Presto, no line.

 

By now a ton of folks have told you Costco gas is just fine as it is top tier. I have been using their 93 octane for years in my Jags. I buy there when I’m shopping there. Otherwise I’m in a grocery store discount program for Shell and buy there.

 

Having myself been in the retail fuel business years ago and have friends still in the distribution and retail fuel sales I can tell you there can be a huge difference in gasoline from place to place.
First off, yes gasoline must meet minimum requirements as mandated. That does not mean it always does nor does it mean it is good enough for your particular application.

Second, not all retail brands sell Top-Tier at all their stations. It is not un-common to find a particular brand that at one station is a Top-Tier seller and then find the same brand retailer at another location that is not. Also, Top-Tier some times does not apply to all grades at that station. Often it may only be their premium that is. So pay careful attention at the pump. SO what is so special about Top-Tier fuel? Well, in a nut shell it reduces the chances of deposits forming, which in turn reduces emissions, improves oil life, and over the life of the engine will help maintain efficiency and increase it's life. Considering the cost of major maintenance or repairs, it is cost effective for the long time owner.

Third, a retail brand name does not sell the exact same gas all over the country. In any given area, the fuel is tailored to meets the requirements in that specific area/region. Gasoline is made up of various simple, complicated, long and short chain molecules. Those molecule blends allow the fuel to operate better in certain areas. (think about winter fuel blends as an example) So take some one who lives in a mountainous area all the time would require a different fuel blend than some one who lives on the ocean coast.

It is true that most gasoline is distributed through a common terminal in any given area, but that does not mean it is the same gasoline. When I worked at an Amoco gas station, just about every station, Shell, Phillips 66, Bob's Gas-N-Eats etc. in the area got most of their fuel from the Marathon terminal just out side of town. However, they did not always get the same gas. Since it would be cost prohibitive to have a pipe line for each refiner to seller, gasoline is often shipped through common carrier pipe lines to the fuel terminals. In between those shipments is what is called "plug gas" which ends up being a blend between the two. Typically that gas is distributed through the cut rate stations. Since it would be impossible to completely separate as an example Shell from Amoco, a slight intermingling does take place. But in between that mingle is where it is more 50/50 aka plug gas. Through identifiers and testing the fuel as it arrives at the distribution terminal it is directed into the correct bulk tank for the retailers. Some retailers national tho different in name do share common base stocks. And that's where the additive package comes in. Some additive packages are better than others and really can make a difference. Some additives are more hype than others. And in some instances some of it is very specific to the brand and is shipped alone. In our case at the Amoco station, I said most of our fuel came from the Marathon terminal a few miles away. However our premium (Amoco Ultimate) was through a different terminal 70+ miles away owned by Amoco and trucked to our station. Since regular gas is the most common sold, local distribution centers are more prevalent and make sense. But with premium fuel being used less often and being a flagship closely controlled by Amoco, same as most other large brands would watch their best fuel they want to be able to assure you are getting exactly what you are paying for.

I diagnose and repair vehicle problems, and I can attest that taking a customer who always buys the cheapest cut rate fuel and has a drive-ability problem, If I suspect the fuel caused the issue I will suggest running several tanks back to back of a quality fuel before attempting anything further. About 90% of the time, it solves their problem. Then they do not need that injector flush and de-carbonation after all. So, say the cost per gallon is 1 dollar higher for the fuel I recommend and they run 40 gallons through and it solves the problem, and it cost them $40. And say an injector flush would cost them $120 or more not to mention what a de-carbonation would cost. Wouldn't you agree that a few tanks of gas are well worth the effort and easier on your wallet?

 

Wow, 455 hp. Makes me think of how much it would take for my 2001 XKR stock 370 hp to get close to your level of snap. Do you have any recommendations? I have had car for 11 years and just tipped 32K miles on it. Runs well but doesn't keep up with the techn cars have today. Don't really like getting shown up by a 4 banger. Maybe my supercharger needs a tune?

 

Not in Michigan where these ID10Ts will stretch the hose over their car and then get frustrated when it barely reach.

 

Great info and I used to shell gas; however, I have put it in my VW three times (it requires premium) and had sputtering and other related issues each time. My local Kroger is quite busy and they have 93 - been running it for years in numerous performance cars without issue.

If you would indulge, what are your thoughts on BG fuels system treatment and cataclean? I use both in my cars about once a year (each gets driven less than 3k annually) and my reasoning is that it will minimize build up, and the chances that I will have O2 sensor issues etc. if I get better economy all the better but I do it to prolong the life of the engine and minimize potential repairs.

 

Was a survey done over here for a well know tv car program Shell Premium came out top , but never had an issue using costco premium

 

Top Tier administer the Detergent Gasoline program on behalf of its 10 auto manufacturers sponsors. Those sponsors are Audi, BMW, GM, FCA, Ford, Honda, Toyota, Mercedes, Navistar, VW, Detroit Diesel. The program is based on a performance specification created by the sponsors to minimize deposits on engine components and help maintain optimal engine performance. The TOP TIER program allows the use of ethanol up to 15% in gasoline/ethanol blends. It's a new class of fuel that helps keep engines cleaner for optimal fuel economy, improved engine performance and lower emissions. It is based on a fuel performance standard developed by BMW, GM, Honda and Toyota. Costco gas may be the cheapest in town, but it's still high-quality. Kirkland Signature fuel meets Top Tier standards, which means it has deposit control additives to clean your engine and help it run more efficiently. It doesn't matter whether you buy regular or premium grades of fuel, you're always getting Top Tier gas at Costo.
The 91 Octane at their gas stations in Canada do not contain ethanol.
Ethanol boost the octane but reduce the BTU of the gas = efficiency of the gas. In Ontario Canada most of the gas contains ethanol. Only very few of them has the 91 ethanol.free. Ethanol free gas is very important for an optimal combustion in your engine.
If you want a good efficient additive to clean your fuel systems I would recommend
- BG44K PN208. It vanquishes deposits in combustion chambers, intake manifolds, ports and on valves and restores flow in fuel injectors. Basically, it cleans the entire fuel system.
- Ethanol Fuel System Drier PN281, it defends engines against the water that accumulates in ethanol blended fuel.
Each product to be added separately to a full tank of gas.
On a personal note, I drive a 2004 XJ8 with 203000 miles. I used the BG44K and Ethanol Fuel System Dryer and run the car on Costco 91. Very smooth engine, no problems and on the Hwy 35 mpg!!!

 

Personally my self and you as some one who also has a few vehicles that rarely get driven, BG fuel treatment, Stabil and a couple of others used in moderation are an excellent way to preserve fuel life for a while. Keeping the tank full and not near empty with a quality fuel (avoid alcohol if possible) will also help preserve it's life. As for the catalyst cleaning products, I am a bit on the fence about those. I have seen reports where constant use of them may have lead to premature catalyst failure but also have seen and used them to bring a borderline failing cat back to life enough so the emissions test would pass. Some cars just have really bad catalyst designs that are prone to failure from thermal shock (hot cat, icy cold water makes for bad juju) some are undersized and get over worked and some are over sized and never get entirely up to temperature and start to soot up from infrequent use and short trips.

 

What really chaps me is the stations that have one way only traffic controls, in an area where the predominant vehicles in use only have the filler on the same side and yet have hoses so short that you cannot stretch it to the other side.

 

I use each basically once each year - this is my first time with the catalyst cleaner but my vehicles are all various ages/types/mileage. Only one has normal mileage but I figured it would at least delay having sensor issues or prolong overall life. The bg stuff, I have been using for years and kind of the same way, once a year. Only one of ours takes regular gas and I try to run a few tanks of premium each year, plus the BG, and I did a full preventative maintenance Program at around 60k (brake fluid, injectors, differential etc.). Hard to tell what works and what would happen without using it but I would rather spend an extra $120 each year on some stuff that might keep me from spending $800 on a repair, and fingers crossed, haven’t had a repair of note in a long time.

 

I’ve never seen higher than 93 anywhere in East Coast. Works fine with the stage 2.

 

Prices in Houston for Reg 87 Octane & Premium 93 Octane:
Costco - Top Tier $1.59 $1.99
Chevron - Top Tier $1.85 $2.19
Shell - Top Tier $1.79 $2.89
HEB - non Top Tier $1.71 $2.25

We usually buy both Chevron & HEB (grocery store brand), right in front of neighborhood, but will fill up when shopping at Costco since it's slightly cheaper but 7 miles away.

 

Damn Shell! They really think they're that much better than everyone else?