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  #1  
Old 12-29-2008, 11:39 PM
Incubus Incubus is offline
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Does brand of gasoline really matter?

I got in an argument with a friend of mine regarding brands. She insisted that brands had a difference in the performance of gasoline, and that brands that put 'additives' like Chevron with 'Techron' were better for your car. I had argued that most different brands all buy/obtain their gasoline from the same refinery, thus any 'additives' are already there, and they price their product more based on demand than perceived 'quality'.

This isn't a question regarding Octane rating, something I already understand. It has more to do with whether Chevron is better for your car than Rotten Robbie, etc. I'm pretty sure its all the same gasoline more or less...right?
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  #2  
Old 12-29-2008, 11:42 PM
GilaB GilaB is offline
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No cite, but I've read that years ago, Consumer Reports tried to put together a piece comparing different gasolines, but couldn't do anything with it because even after many thousands of miles, there was no apparent differences in how the cars drove.

That said, I've known a few people who avoided particular gas stations (both independent and part of larger chains) because they claimed that the gas at those stations had been adulterated, harming their engines.
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Old 12-30-2008, 12:46 AM
stanger stanger is offline
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I can't come up with a cite, but I remember reading some years ago that the refineries made a basic gasoline stock that was used by most everyone. Either at the refinery, or at the next location in the chain, the gasoline stock was pumped into tanker trucks. It was at this stage that the different additives were mixed in.

This stage had all the additives ready to go, and you dialed in what type of additives you wanted, depending on what brand of fuel and location the truck was going to, and the additives were mixed in with the stock at that time. It was at this point that the fuel became brand or application specific.
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  #4  
Old 12-30-2008, 12:54 AM
Enola Straight Enola Straight is offline
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I think I remember something on these boards of how a certain compound in Shell or Sunoco gas would adversly react to a plastic component in Ford intake manifolds.
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  #5  
Old 12-30-2008, 01:31 AM
t-bonham@scc.net t-bonham@scc.net is offline
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All gasoline in Minnesota comes into the state through one of 3 pipelines, and is refined at one of 2 refineries, either the Koch refinery in Pine Bend or the Marathon refinery in St. Paul Park. (Some areas of the state do get gasoline from refineries across the border, in Superior, WI or North Dakota.)

I find it hard to believe that there could be any significant differences between brands of gasoline, when they all come from the same oil, processed in the same refinery. The differences would have to be the result of additives mixed with the gasoline, and those are just a tiny percentage of the mixture.

Also, many of the additives are not unique to any particular brand of gasoline. Most brands add a combustion catalyst, a polymerizer, etc. Often these are not even from the oil companies themself, but from chemical companies that sell them (or slightly different formulations of them) to several oil company brands.

Last edited by t-bonham@scc.net; 12-30-2008 at 01:31 AM..
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  #6  
Old 12-30-2008, 03:52 AM
clayton_e clayton_e is offline
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Many years ago I worked at a family owned gas station that was of a major brand. It was well known within the business and others of the same brand that the largest state wide competitor's gas was "watered down" (the chain, if not completely, is 95% within the state). I had no proof that it was or wasn't since the day I heard it and I have none for or against it now.. But I called bullshit without a study. I didn't care enough about a minimum wage job to tell my bosses prove it.. I just pumped the gas, nobody ever was told to tell the customer that the gas was better.. just show me something non-anecdotal, even if you don't understand the scientific process at least try.. and Ill only buy from my own gas station ever. Nobody ever did and I always bought from where I was closest to running out of gas. Screw the two cent per gallon difference. I'd rather not run around the area wasting time to save a total of 30 cents.
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  #7  
Old 12-30-2008, 05:54 AM
Fubaya Fubaya is offline
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All companies get their gas from the same terminal then add their own additives to it. They make an honest attempt to stick out from the competitor, so their additives probably do what they're supposed to do. But they're all using the same science and I suspect all the different additives are pretty much the same.
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  #8  
Old 12-30-2008, 10:40 AM
Yorikke Yorikke is offline
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Quote:
Originally Posted by clayton_e View Post
Many years ago I worked at a family owned gas station that was of a major brand. It was well known within the business and others of the same brand that the largest state wide competitor's gas was "watered down" (the chain, if not completely, is 95% within the state). I had no proof that it was or wasn't since the day I heard it and I have none for or against it now.. But I called bullshit without a study.
It's pretty easy to get caught doing this. All it takes is one guy who thinks his car is pinging more than usual to make a complaint, and the people from Weights and Measures will be on site to analyze the gas, or at least keeping their eye on you...

Joe
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  #9  
Old 12-30-2008, 11:08 AM
Hunter Hawk Hunter Hawk is offline
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GQ response: I believe Rick weighed in on this topic a while back, and IIRC he noted that some brands were in fact better than others. You might want to do some searching to see if you can turn up his replies.

IMHO response: In my experience, my car (1992 Volvo) does seem to run better and start more easily when I'm using Chevron/Shell gasoline than when using Arco gasoline.
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  #10  
Old 12-30-2008, 11:13 AM
neuroman neuroman is offline
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Quote:
Originally Posted by wheresgeorge04 View Post
It's pretty easy to get caught doing this. All it takes is one guy who thinks his car is pinging more than usual to make a complaint, and the people from Weights and Measures will be on site to analyze the gas, or at least keeping their eye on you...

Joe
Or if you're in Oklahoma, the Weights & Measures people will completely ignore you, despite the fact that you just filled up your 12.5 gallon capacity tank with 12.8 gallons of gasoline (and the car drove into the station under its own power).
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  #11  
Old 12-30-2008, 11:29 AM
running coach running coach is online now
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Quote:
Originally Posted by neuroman View Post
Or if you're in Oklahoma, the Weights & Measures people will completely ignore you, despite the fact that you just filled up your 12.5 gallon capacity tank with 12.8 gallons of gasoline (and the car drove into the station under its own power).
Gas tanks have extra space for expansion. You would have a case if you always filled 12.5 at other station and 12.8 at one in particular. I think also that the tank might hold more than the stated capacity.l
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  #12  
Old 12-30-2008, 11:37 AM
Mikemike2 Mikemike2 is offline
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I worked at a gas station for a couple of years during college. Water and gas don't mix and if there is water it sinks to the bottom of the holding tanks. We used a chemical on a long stick that reacts to water to regularly check our tanks. Never once did it turn pink, and yes I tried holding it under a tap and it immediately changed color.

That didn't stop many customers from complaining that they had gotten water in their tank from us and we had ruined part of their engine.
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  #13  
Old 12-30-2008, 01:11 PM
DrDeth DrDeth is offline
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Quote:
Originally Posted by Incubus View Post
I got in an argument with a friend of mine regarding brands. She insisted that brands had a difference in the performance of gasoline, and that brands that put 'additives' like Chevron with 'Techron' were better for your car. I had argued that most different brands all buy/obtain their gasoline from the same refinery, thus any 'additives' are already there, and they price their product more based on demand than perceived 'quality'.

This isn't a question regarding Octane rating, something I already understand. It has more to do with whether Chevron is better for your car than Rotten Robbie, etc. I'm pretty sure its all the same gasoline more or less...right?
Chevron does add Techron, and it is an additive that adds value, it's a detergent, keeps your engine cleaner. Now sure, Chevron does sometimes sell excess gas with Techron to Rotten Robbe but RR gets their gas from many sources.

It's generally OK to use "cheap gas" sometimes, then run a tank full of "the good stuff" for detergent reasons.
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  #14  
Old 12-30-2008, 01:17 PM
Santo Rugger Santo Rugger is offline
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Quote:
Originally Posted by Hunter Hawk View Post
GQ response: I believe Rick weighed in on this topic a while back, and IIRC he noted that some brands were in fact better than others. You might want to do some searching to see if you can turn up his replies.
IIRC he uses Chevron gas, in part because when standards were raised for top-tier gasolines, Chevron was the only one who didn't have to reformulate.
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  #15  
Old 12-30-2008, 01:34 PM
ivn1188 ivn1188 is offline
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There have been a few recent cases about gasoline brand advertising. Claims that a certain brand will make your car run cleaner or better or have less maintenance are false advertising under FTC regs, UNLESS the company can show that it's claims are true with decent research.

The problem for the gas companies is that the Federal regulations on gasoline and its additives are very strict; there isn't much room to play around. I guarantee if one of these companies had some miracle additive that made it a better brand of gasoline, they would be advertising that fact -- but no one is. Also as talked about above, the gasoline itself comes from the same places and additives are put in before delivery in order to brand the gasoline.

When I worked in a gas station, I had to do weekly water checks. There was always an inch or two of water in the tank because of condensation, etc, but the gasoline was always dry. We had the same pink testers that mikemike mentoned, and they are sensitive enough to turn pink from humidity in the air. We also had state and fed inspectors in about monthly (without notice) who would test the gasoline and the pumps to make sure they were calibrated properly. Underground gas tanks also have sensors that instantly shut off the flow if the pump starts pulling water (they use centrifugal or other density checkers).

As per detergents in gasoline, they are highly regulated and all gasoline sold must contain the federally specified amounts of detergent of the approved types. The "Top Tier" specifications are something you can look at, but those are made by some auto manufacturers. Some people claim that the top tier ratings are a marketing device like the J.D. Power awards, etc. Either way, you aren't going to get "buildup" even with cheap gasoline. You can just run concentrated techron or J-power or whatever through every 50k miles. Also important to note is that the addition of detergents to gasoline reduce your fuel milage, since there is less fuel per volume.

Brand name gasoline might offer a very slight advatage in the cleaning department, but it's probably not statistically significant, and even if it is, it's probably not worth driving farther or paying more to get a certain brand.
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  #16  
Old 01-05-2009, 05:36 PM
neuroman neuroman is offline
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Quote:
Originally Posted by runner pat View Post
Gas tanks have extra space for expansion. You would have a case if you always filled 12.5 at other station and 12.8 at one in particular. I think also that the tank might hold more than the stated capacity.l
No, I don't think so. I believe the stated capacity is the real capacity. For one thing, if I fill up around the time the "warning light" first appears, I use about 9.5 to 10 gallons to top off. And I have never, before or after, used more than about 11.5 gallons to fill up.
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  #17  
Old 01-05-2009, 07:10 PM
Yorikke Yorikke is offline
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Originally Posted by neuroman View Post
No, I don't think so. I believe the stated capacity is the real capacity. For one thing, if I fill up around the time the "warning light" first appears, I use about 9.5 to 10 gallons to top off. And I have never, before or after, used more than about 11.5 gallons to fill up.
Sorry, You're wrong. First google result. (PDF File)

Joe
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  #18  
Old 01-06-2009, 11:51 AM
GusNSpot GusNSpot is offline
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In the areas 'QuickTrip' operates, I find that they do a better job of filtering & storing their gas. They guarantee it.`Don't know about the additives they do or don't add.

I do not fill from tanks that the tanker truck has just filled on general principals of stirred up stuff.

When operating diesel engines, I try to go to places that have a lot of fuel sales. An ex-wife ruined an injector pump with a load of bad fuel from a rat hole out store in the country who had a low price. Grr, Told her and told her to never do dat...

Last edited by GusNSpot; 01-06-2009 at 11:54 AM.. Reason: poor proof reading
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  #19  
Old 01-06-2009, 06:27 PM
AngelSoft AngelSoft is offline
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I dunno, I hear people say there's no difference but there is a definite difference in my gas mileage depending on where I fuel up. Shell and Chevron give me about 20mpg however the 'cheap' gases like AMPM give me a good 23-25mpg.
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  #20  
Old 01-06-2009, 08:43 PM
ivn1188 ivn1188 is offline
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Originally Posted by AngelSoft View Post
I dunno, I hear people say there's no difference but there is a definite difference in my gas mileage depending on where I fuel up. Shell and Chevron give me about 20mpg however the 'cheap' gases like AMPM give me a good 23-25mpg.
Are the Shell and Chevron adding more ethanol? Lots of places have 10% ethanol added to gasoline.
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  #21  
Old 01-06-2009, 09:07 PM
AngelSoft AngelSoft is offline
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Originally Posted by ivn1188 View Post
Are the Shell and Chevron adding more ethanol? Lots of places have 10% ethanol added to gasoline.
I honestly have no idea. But I'd much prefer to get Chevron since in my town it's the same price as the 'cheap' gas and it's better for my car. But the gas mileage difference is enough to make sure I stay with the cheap place.
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  #22  
Old 01-07-2009, 09:32 AM
Santo Rugger Santo Rugger is offline
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Originally Posted by AngelSoft View Post
I honestly have no idea. But I'd much prefer to get Chevron since in my town it's the same price as the 'cheap' gas and it's better for my car. But the gas mileage difference is enough to make sure I stay with the cheap place.
Not if it has ethanol in it. There should be a sticker on the pump, I try to avoid those places. It's awesome now, ethanol is more expensive than gasoline, so it's easier to find the places that use 100% gas (or, at least more pleasurable!).
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  #23  
Old 01-07-2009, 09:52 AM
Really Not All That Bright Really Not All That Bright is online now
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Every station here has 10% ethanol.
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Old 01-07-2009, 10:05 AM
AngelSoft AngelSoft is offline
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Originally Posted by Santo Rugger View Post
Not if it has ethanol in it. There should be a sticker on the pump, I try to avoid those places. It's awesome now, ethanol is more expensive than gasoline, so it's easier to find the places that use 100% gas (or, at least more pleasurable!).
Well next time I gas up I'll check. I use the cheap stuff for my car and my mom insists on Chevron for hers so I'll compare. It'll be interesting to find out since I had no idea about certain places using Ethanol. Living in Oregon you usually don't pay too much mind to what's posted on the pumps since you normally never even get out of your car.
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Old 01-07-2009, 11:41 AM
Quercus Quercus is offline
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Originally Posted by AngelSoft View Post
I dunno, I hear people say there's no difference but there is a definite difference in my gas mileage depending on where I fuel up. Shell and Chevron give me about 20mpg however the 'cheap' gases like AMPM give me a good 23-25mpg.
Just curious, how did you figure this out? (How many tanks of each did you use for your tests?)
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  #26  
Old 01-07-2009, 11:44 AM
sweeteviljesus sweeteviljesus is offline
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I thought all gas now had 5 or 10% ethanol (depending on winter or summer blend) as a replacement for MTBE which is a now-outlawed octane booster. Is this not the case?

FWIW,
Rob
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  #27  
Old 01-07-2009, 11:59 AM
Santo Rugger Santo Rugger is offline
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Originally Posted by Quercus View Post
Just curious, how did you figure this out? (How many tanks of each did you use for your tests?)
I personally use the GPM calculator on my car. I average about three or for MPG less in my car than AngelSoft does, but the results are similar for gasoline vs. ethanol blends. I stare at the thing all the time, resetting it sometimes, letting it run for a tank at others. The results are pretty consistent.

sweeteviljesus, it may depend on the state? Some require 10% blends (Florida and Michigan?). I think they change the blends at different times of year, but it seems to me that they'd have to change the rating on the pump if they changed the octane.

Last edited by Santo Rugger; 01-07-2009 at 11:59 AM..
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  #28  
Old 01-07-2009, 12:00 PM
AngelSoft AngelSoft is offline
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Originally Posted by Quercus View Post
Just curious, how did you figure this out? (How many tanks of each did you use for your tests?)
I've done it on several occasions. Sometimes Chevron/Shell will be more convenient, or cheaper. As for number of tanks, probably between 5-10 over the past year.
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  #29  
Old 01-26-2009, 08:15 PM
neuroman neuroman is offline
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Originally Posted by wheresgeorge04 View Post
Sorry, You're wrong. First google result. (PDF File)

Joe
Thanks for the information. This more or less proves my point, however, as it states that capacity varies by "up to 3%" of the manufacturer stated volume. 103% of 12.5 gallons is 12.875 gallons... which still leads me to conclude that I was cheated at the pump.
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  #30  
Old 01-26-2009, 10:47 PM
Rick Rick is offline
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Quote:
Originally Posted by Hunter Hawk View Post
GQ response: I believe Rick weighed in on this topic a while back, and IIRC he noted that some brands were in fact better than others. You might want to do some searching to see if you can turn up his replies.

IMHO response: In my experience, my car (1992 Volvo) does seem to run better and start more easily when I'm using Chevron/Shell gasoline than when using Arco gasoline.
Quote:
Originally Posted by Santo Rugger View Post
IIRC he uses Chevron gas, in part because when standards were raised for top-tier gasolines, Chevron was the only one who didn't have to reformulate.
Both of you are correct. I tend to run Chevron as my default fuel, I will also go with Shell, or Union 76 if there is no Chevron nearby. All three of these are top tier fuels. IIRC Chevron did not have to reformulate to meet this requirement. Cite Also The big three car makers run their EPA certification tests on Chevron. Which means they have to truck in it, since Chevron does not sell their gas in Michigan. Cite
Maybe I am a bit warped in my perspective but I have seen cars with driveability problems get fixed by only a change in fuel. That makes it a bit hard for me to swallow there is no difference, all fuels are the same.

Quote:
Originally Posted by neuroman View Post
Thanks for the information. This more or less proves my point, however, as it states that capacity varies by "up to 3%" of the manufacturer stated volume. 103% of 12.5 gallons is 12.875 gallons... which still leads me to conclude that I was cheated at the pump.
Depending on the car and the tank, the stated capacity and what you can get into it can vary by a gallon or two. I once put 20 gallons into a tank that was supposed to be 18.4 gallons. Of course this took a bit of extra time, rocking the car to get all the air bubbles out, and the fuel was all the way up the neck when it was done, but that car was FULL when I got done.
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  #31  
Old 01-26-2009, 10:53 PM
Hilarity N. Suze Hilarity N. Suze is offline
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anecdotal: In my Infiniti it really did matter. I once bought some gas at a 7-11 and it completely shut my car down. It ran notably better when I used Chevron or Texaco.

Of course, being a luxury car, it needed the highets octane available, as well. Picky little thing.

It has never mattered in any other car I've driven.
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  #32  
Old 01-27-2009, 07:47 AM
Joey Tightlips Joey Tightlips is offline
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Originally Posted by Santo Rugger View Post
Some require 10% blends (Florida and Michigan?). I think they change the blends at different times of year, but it seems to me that they'd have to change the rating on the pump if they changed the octane.
Here in VA (at least at the station I go to) the sticker says something along the lines of "may contain up to 10% Ethanol". That way they have themselves covered whether it's 10%, 5%, or 0%. Imagine that, a gas station doing something reasonably wise.
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