Hi Guys,

I have always used Chevron or Unocal premium gas in the FD. Never wanted to risk a lower quality premium fuel. We get 91 octane premium in CA. Is Costco premium good enough? Thoughts?

Thanks

Mods in sig with "safe tune", running 13-14 psi

 

It's so hard to separate truth from spin... I'm not sure we'll ever know with all the marketing that is out there.

It seems like you're more worried about detonation than detergents so, in that sense, the gas is probably the same. From what I understand, the difference is in the additives that each company adds (like Techron) and in which amounts. Supposedly, this makes a difference in keeping the engine cleaner in the long run, but as a fuel, it seems the same.

If you feel like reading, I pulled this off of some statistics website, written by a trucker who hauled gas.

"I've been in the petroleum hauling business for over ten years now. We haul exclusively to one customer from various oil terminals in the Virginia/North Carolina area. I've been authorized to load at over a dozen terminals in a 300 mile radius in recent years. I occasionally still drive, but my normal job is dispatching ten tanker trucks to our area stations.

What I can tell you about "branded" gasoline is this: Sometimes it ain't what you think it is. And the additives which are put into the branded gasolines are added in such small amounts it may or may not have the advertised effects on your engine/fuel system.

Of course the states regulate the octane advertised on the pumps, but no agency (to my knowledge) ever checks for the additives which are purported to be present in the branded gasolines.

It then becomes possible for branded stations to sell gasoline which doesn't have the additives that the signs and commercials say that it has. This can occur when the additive injector system fails at the loading terminal, or when the terminal runs out of an additive.

Additives in gasoline are just like additives in oil; they are "added" to the base product. All gas begins as pretty much the same stuff. Regular unlead and premium for all oil terminals in a given area comes up the same pipeline. We pull off of Colonial Pipeline in this area, and a small bit off a branch pipeline called Plantation Pipeline. When Citgo, Chevron, Conoco, Amoco, Texaco, Shell, and the rest fill their huge terminal storage tanks the gas comes off the same pipeline at pretty much the same time. There is one exception: Amoco Ultimate Premium is refined an extra step, and it comes up the pipeline all by itself. Other company's 93 octane premium fuels (I don't know anything about Sunoco fuels as they aren't distributed in my area) are the same before the additives are injected into the gasoline when it is being loaded onto the transport tanker trucks.

There are a couple of different octanes out there for what can be called "premium" gasoline. Read the pump. If it's 92, that ain't bad. 93 is better. If it's 91 I'd definitely pass. The lower octane premiums are simply cut a bit with regular unleaded. That's also where "midgrade" or "plus" gasoline comes from; it's mixed as it goes on the tanker truck--35 percent premium and 65 percent regular in most cases.

The quality of gasoline in the pipeline must meet certain standards, of course. This doesn't mean it will always be exactly the same, however.

It is possible that your car will respond well to one particular company's additive. It's possible, but I think if you really tested the notion well you'd find other explanations for why your performance and/or mileage was up/down based on your choice of gasolines. I do know that Chevron's Techron works when I pour 12 ounces into my car's tank, but I don't know if the concentration of Techron in Chevron's gasoline is high enough to really do much. Think about it: If that stuff is actually worth fifty cents an ounce, and the recommended dose is about one ounce per gallon of fuel in your tank, it would run the cost of the Chevron branded gasoline up way too much to be competitive. Unless, of course, there are only trace amounts of the Techron in the branded gas, which is the case.

When you get into unbranded gasolines you're in a "whole 'nother world." Unbranded gasoline can come from any terminal out there. It's the cheap gas of the day. This doesn't mean that the gas is no good, it simply means that if Conoco/Phillips has the best gasoline price of the day, it's a safe bet that's where your local Racetrack, Sheetz, Wilco/Hess, or fill in the blank got their fuel from.

Most of us cannot tell any real difference between Shell branded or Chevron branded gasoline and what our local chain convienience (unbranded) stores sell. And that's not surprising since the base fuel is exactly the same stuff. Shell, Chevron, and unbranded gasolines all comes up the pipeline at the same time; it's the same stuff. Only the miniscule additive package makes it any different.

We've all heard "Don't buy _______ gas because they put water in it." This is absurd for more reasons that I've got time to sit here and type out. But the most glaring flaw in this twisted logic is that gasoline and water don't mix. The water settles to the bottom of the tank. The sumps are set at 12 inches off the floors of oil terminal holding tanks and water checks are made daily (and required by law). It's nearly impossible for water to be loaded onto a gasoline tanker truck and subsequently delivered to the customer.

If you do find water in a retailer's gasoline, it got there by leaking into his ground tanks. This does happen, of course. Most newer stations have Veeder-Root tank monitoring systems these days. This system will sound an alarm if water is present in the ground tank.

So basically I just shop price for my personal gasoline. There's a chain in this area called "GO-Mart" which tends to keep the prices down. I rarely buy a full tank of gas from any branded retailer anymore. While the additives that the big gasoline retailers use are only used in very, very small amounts, they are in there. And this (along with national advertising campaigns) runs the cost of the branded gasolines up. And since I can't see any difference in my vehicles I can't justify the higher prices of the branded gasolines.

If I could recommend purchasing gas from any retailer, I would say go to the retailer that moves the most gasoline. His tanks are probably the cleanest. His gasoline is probably the freshest off the pipeline. His ground sump and dispenser filters are going to be changed much more often. Since his business plan is obviously to sell maximum volume, he'll be meticulous in keeping filters maintained, and he'll have a fuel tank monitoring system (the Veeder-Root system mentioned earlier) which will alert him if water is ever present in his tanks.

 

Great read thanks!

 

I get mine from sams club for all my cars.

 

I go to places that seem to have higher vehicle traffic to get fresher gas. So a place like a discount gas station is probably a safer bet than some name brand gasoline in a low traffic area.

 

Sam's club = Wal Mart

Costco = still a large corporation with morals that seeks the best quality for a fair price and compensates employees fairly


slight difference there that i figured was worthy of mentioning, since sam's club and wal mart fuels are likely bottom of the barrel. for the most part it is about the additives and ethanol content, since the knock ratings on the pump are tested and have to meet rather strict guidelines, so you won't be getting a tank of crappy 87 from a pump that is labelled 91, sometimes water does get into the tanks but that can happen anywhere. i used cheap gas in my TII for long trips and it never caused excessive carbon buildup or knock that blew up the engine, people are a little overly paranoid about fuel.

 

ANY corporation as large as Costco would not survive if their marketing plan was to be moral, fair, and provide the highest quality possible at a "fair" price.

Their goal is to profit as much as possible, just like any other corporate giant, telling yourself otherwise is silly.


That being said, if you prefer their fuel because they give you the warm and fuzzy...

 

I think Sam's club probably has the highest through put of any gas station I have seen. That place is always slammed with people.

It does all come from the same refinery.

What additive in the gasoline is going to prevent detonation?

I do sometimes get gas at a local loaf N jug as well. I haven't had any problems with any of my cars ever.

I do know of a few people who blew their engines up at BP and ExxonMobile. The company covered the costs of their engines when they accidently put diesel in the 87 octane tank.

 

When I lived in CA, I did notice that the chevron gas station next to UCLA off wilshire blvd did give me better fuel mileage on my Honda prelude. that is the only gas station I ever noticed a difference...and it was only for MPG. Perhaps it was a tail wind too.

 

a discussion for another thread, however i have known employees who worked for both companies and also the difference in quality from each isn't hard to distinguish either, but yeah...

for knock suppression, doesn't matter if you buy your gas at wal mart or a fancy chevron station.

 

I've always just made sure I put some techron in every few fill ups. Maybe 4 fills with Valero, then 1 with Chevron.

There's no special well for Shell, Chevron and Exxon. They just add detergents to keep your injectors clean, then charge you for it.

 

This. I work for a company that is heavily involved in energy and this is exactly what is done. All gasoline comes from the same central storage where different companies tankers fill up and add their respective additive.