Premium gas at BJ's for Mercedes

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dollarsaver
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Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 9:33 am

Hi all,
My first service due at MB dealer. Check engine light is on for about a week. Dropped the car off at the dealer who mentioned that I should not use gasoline at BJ's Warehouse because it has higher quantities of water and alcohol. He did not imply that the check engine light was directly linked with use of the gasoline. He did suggest only name brands of gasoline at the appropriate octane level.

Anyone know of any reason not to use BJ's gasoline? I had a C300 for 6 years with no issues using BJ's gasoline 93 octane.

Thanks in advance

lurker0987
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Re: Premium gas at BJ's for Mercedes

Post by lurker0987 » Thu Jan 18, 2018 9:45 am

I have used BJ's premium gas for over a decade with my MB. Never had a problem.

Check the pumps for date of last inspection and talk to the manager to identify their gasoline supplier. (hint, probably not BJs) Dive deeper and research the supplier. Here is an interesting link for more context http://www.toptiergas.com/

neilpilot
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Re: Premium gas at BJ's for Mercedes

Post by neilpilot » Thu Jan 18, 2018 9:47 am

I have no experience, except to say that BJ's isn't a TopTier supplier. However, there are many reasons not related to gas quality that could result in illuminating the check engine light. Did the dealer give you the error code(s) that triggered the light? Other than a simple reset, what was done to prevent those error codes? This information will help you determine of the code could have been fuel related.

Spirit Rider
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Re: Premium gas at BJ's for Mercedes

Post by Spirit Rider » Thu Jan 18, 2018 9:53 am

I seriously doubt that BJ's has higher percentages of water unless there has been specific problems at that specific BJ's. Sounds more like FUD to me.

However, it is likely that Mercedes recommends the use of top tier gasoline. Top tier gasoline has better detergent and additive packages. Engine teardown studies have shown reduced deposits and other benefits of using top tier gasoline.

The BJ's near you may or may not provide top tier gasoline. You should be able to determine this. It is your choice whether to use top tier gasoline or not. One other option is to use top tier gasoline every 4 - 5 fill ups or add fuel system treatments every 8 - 10 fill ups.

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lthenderson
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Re: Premium gas at BJ's for Mercedes

Post by lthenderson » Thu Jan 18, 2018 10:01 am

dollarsaver wrote:
Thu Jan 18, 2018 9:33 am
the dealer who mentioned that I should not use gasoline at BJ's Warehouse because it has higher quantities of water and alcohol.
I have no experience with Mercedes or BJ's gasoline but I used to have lots of problems with check engine lights on two of my vehicles when using ethanol blended gasoline. I switched several years ago to only using non-ethanol gasoline (regardless of octane since around here there is only one option without), and all those problems went away on the two vehicles always having the problems.

Jack FFR1846
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Re: Premium gas at BJ's for Mercedes

Post by Jack FFR1846 » Thu Jan 18, 2018 10:09 am

Have you ever seen either a supply tanker truck driver or gas station attendant with one of those 12 foot sticks, putting it into the gas tank to measure the level? They do that to measure the level vs what's been put into and taken out of the tank as gas. Condensation continuously turns into water in the tanks and when it gets to a pre-determined level, it's removed. All gas stations have some level of water at the bottom of the tank.

Did you get gas while a tanker was there, pumping in gas and churning up the crap at the bottom of the tank? That could happen at any gas station.
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wrongfunds
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Re: Premium gas at BJ's for Mercedes

Post by wrongfunds » Thu Jan 18, 2018 10:17 am

If you do not know the actual code of the check engine light, it just means that you donated your hard earned money to the repair shop. I can't believe any intelligent person would talk about check engine light without knowing the actual code behind it.

neilpilot
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Re: Premium gas at BJ's for Mercedes

Post by neilpilot » Thu Jan 18, 2018 10:28 am

The amount of dissolved water in gasoline is typically a function of two variables, the temperature of the liquid and the concentration of ethanol in the gas. Disregarding temperature, which would typically be the same for any branded gas, then the question is % ethanol. Where I live, unless you buy ethanol-free gas all pumps are labelled "up to 10% ethanol". Unless BJ's % ethanol is higher than those other brands or the tank has been recently agitated (per Jack FFR1846's post above) the amount of water is the same as those other brands.

runner3081
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Re: Premium gas at BJ's for Mercedes

Post by runner3081 » Thu Jan 18, 2018 11:00 am

dollarsaver wrote:
Thu Jan 18, 2018 9:33 am
Hi all,
My first service due at MB dealer. Check engine light is on for about a week. Dropped the car off at the dealer who mentioned that I should not use gasoline at BJ's Warehouse because it has higher quantities of water and alcohol. He did not imply that the check engine light was directly linked with use of the gasoline. He did suggest only name brands of gasoline at the appropriate octane level.

Anyone know of any reason not to use BJ's gasoline? I had a C300 for 6 years with no issues using BJ's gasoline 93 octane.

Thanks in advance
It shouldn't be an issue. We have an older Mercedes that requires premium and we run 91 Octane from Sam's Club in it (highest readily available in AZ). No issues.

We have also bough gas at some shady stations in the middle of nowhere on road trips and never had a problem.

TBillT
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Re: Premium gas at BJ's for Mercedes

Post by TBillT » Thu Jan 18, 2018 11:52 am

Ditto I usually use TopTierGas.com, but I have not heard a problem with BJ's.
The other consideration is where you live, here in northern Virginia we have EPA RFG (reformulated gasoline).
I tend to think that RFG keeps regional gaso quality quite uniform, whereas if you get outside of RFG areas, there is more room for differences between brands including E0.

If the mechanic is saying BJ's has more alcohol, that suggests you are not in RFG area where it is all the same E10 everywhere. Actually there is ethanol mandate for E10 pretty much everywhere, but outside of RFG areas your gaso "may contain" 10% ethanol, whereas in RFG areas you gaso "contains" 10% ethanol. If BJ's is over 10%, like E15, that could be a concern depending on your car requirements.

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 12:06 pm

TBillT wrote:
Thu Jan 18, 2018 11:52 am
Ditto I usually use TopTierGas.com, but I have not heard a problem with BJ's.
The other consideration is where you live, here in northern Virginia we have EPA RFG (reformulated gasoline).
I tend to think that RFG keeps regional gaso quality quite uniform, whereas if you get outside of RFG areas, there is more room for differences between brands including E0.

If the mechanic is saying BJ's has more alcohol, that suggests you are not in RFG area where it is all the same E10 everywhere. Actually there is ethanol mandate for E10 pretty much everywhere, but outside of RFG areas your gaso "may contain" 10% ethanol, whereas in RFG areas you gaso "contains" 10% ethanol. If BJ's is over 10%, like E15, that could be a concern depending on your car requirements.
On the pump at BJ's it is clearly stated that the gas contains 10% ethanol. We live in Southwest Maine on the coast. As I mentioned, my previous MB C300 gave us zero problems for 6 years using the same BJ's. Thanks

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 12:09 pm

wrongfunds wrote:
Thu Jan 18, 2018 10:17 am
If you do not know the actual code of the check engine light, it just means that you donated your hard earned money to the repair shop. I can't believe any intelligent person would talk about check engine light without knowing the actual code behind it.
This first service (which the rep told us would have been $380) was covered when we bought the car. We always buy CPO's for better value The car had 4k miles and was too soon for a 1st service; so, they gave us the first for nothing. Thanks

bhsince87
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Re: Premium gas at BJ's for Mercedes

Post by bhsince87 » Thu Jan 18, 2018 12:21 pm

I work near two fuel blending/distrubtion terminals. One is Texaco, the other Sunoco. The gasiline comes in trhough a pipline, the alcohol in rail cars. I assume the other additives arrive by rail as well.

I see tanker trucks from BJ's (often a private carrier), Sheetz, Wawa, etc. at both terminals from time to time.

It is my understanding that by law, gas stations must meet posted minimum octane and maximum ethanol levels. So BJ's should be fine for that.

If a particular brand is advertised as containg a special additive package, then their dispensed gasoline must contain those additives. That is where gasoline from a place like BJ's etc. might vary from time to time.
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neilpilot
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Re: Premium gas at BJ's for Mercedes

Post by neilpilot » Thu Jan 18, 2018 12:22 pm

dollarsaver wrote:
Thu Jan 18, 2018 12:09 pm
wrongfunds wrote:
Thu Jan 18, 2018 10:17 am
If you do not know the actual code of the check engine light, it just means that you donated your hard earned money to the repair shop. I can't believe any intelligent person would talk about check engine light without knowing the actual code behind it.
This first service (which the rep told us would have been $380) was covered when we bought the car. We always buy CPO's for better value The car had 4k miles and was too soon for a 1st service; so, they gave us the first for nothing. Thanks
So what were the codes? If you don't know, then you definitely got what you paid for. :!:

Rupert
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Re: Premium gas at BJ's for Mercedes

Post by Rupert » Thu Jan 18, 2018 12:33 pm

So my neighbor works for a regional gas distributor. Most gas stations in my region purchase gas from her company because they're basically the only show in town. (Each individual chain adds its proprietary detergents and other additives after they purchase the gas from the distributor). I once asked her what the difference was between the gas you buy at, say, a Shell station versus the gas you buy at one of the independents or local discount chains. She said, for what it's worth, that the discount chains buy gas from them after it has been sitting in their holding tanks for a while. The longer it sits in those holding tanks before being transferred to a tanker truck for delivery, the more condensation occurs. That's why the distributor sells it at a discount.

ssquared87
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Re: Premium gas at BJ's for Mercedes

Post by ssquared87 » Thu Jan 18, 2018 12:43 pm

Only use Top Tier gas. Top tier certifies that the gas has a much greater percentage of detergents than required by law.

Just because BJs is not Top Tier, does not mean that they don't use great detergents, but you can't be certain. If it says top tier, you know that it does. Mercedes suggests using top tier gas.

jcpct
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Re: Premium gas at BJ's for Mercedes

Post by jcpct » Thu Jan 18, 2018 12:46 pm

My BMW refuses to run on BJ's gas, I don't know why. I've tried several times and each time the car runs rough shortly after a fill-up. My RAM pickup does not seem to have the same problem and I run BJ's gas in it all the time. I only use top-tier gas for the BMW now.

ssquared87
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Re: Premium gas at BJ's for Mercedes

Post by ssquared87 » Thu Jan 18, 2018 12:49 pm

Rupert wrote:
Thu Jan 18, 2018 12:33 pm
So my neighbor works for a regional gas distributor. Most gas stations in my region purchase gas from her company because they're basically the only show in town. (Each individual chain adds its proprietary detergents and other additives after they purchase the gas from the distributor). I once asked her what the difference was between the gas you buy at, say, a Shell station versus the gas you buy at one of the independents or local discount chains. She said, for what it's worth, that the discount chains buy gas from them after it has been sitting in their holding tanks for a while. The longer it sits in those holding tanks before being transferred to a tanker truck for delivery, the more condensation occurs. That's why the distributor sells it at a discount.
Great post, a lot of people think the gas at Shell vs. Joe Smith's is the same because its supplied by the same company, but as you mention, its the second rate stuff.

Also, the additives that are added at the station are very different at a Shell or Chevron vs. local no name. Consumer reports had a good writeup on using Top Tier gas
https://www.consumerreports.org/car-mai ... tra-price/

ssquared87
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Re: Premium gas at BJ's for Mercedes

Post by ssquared87 » Thu Jan 18, 2018 12:54 pm

jcpct wrote:
Thu Jan 18, 2018 12:46 pm
My BMW refuses to run on BJ's gas, I don't know why. I've tried several times and each time the car runs rough shortly after a fill-up. My RAM pickup does not seem to have the same problem and I run BJ's gas in it all the time. I only use top-tier gas for the BMW now.
BMW engines and German engines in general have much lower tolerances than American ones, so any variations outside of the norm have a bigger impact.

I've only put Top Tier in my BMW and even amongst the Top Tier brands I can notice subtle differences in smoothness and performance. My 2011 328 ran best on Shell and Chevron, but didn't do so well on Costco or Exxon/Mobil. My 98 M3 doesn't do as well with Costco either. My 2017 530i runs fine on Costco so I just use that.

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 1:06 pm

neilpilot wrote:
Thu Jan 18, 2018 12:22 pm
dollarsaver wrote:
Thu Jan 18, 2018 12:09 pm
wrongfunds wrote:
Thu Jan 18, 2018 10:17 am
If you do not know the actual code of the check engine light, it just means that you donated your hard earned money to the repair shop. I can't believe any intelligent person would talk about check engine light without knowing the actual code behind it.
This first service (which the rep told us would have been $380) was covered when we bought the car. We always buy CPO's for better value The car had 4k miles and was too soon for a 1st service; so, they gave us the first for nothing. Thanks
So what were the codes? If you don't know, then you definitely got what you paid for. :!:
The car is in for service at this writing. I'll check when I get the car tonight. Thanks again

wrongfunds
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Re: Premium gas at BJ's for Mercedes

Post by wrongfunds » Thu Jan 18, 2018 1:07 pm

"How do you know the guy behind the service counter is lying?"
"His lips are moving"

Unless you know otherwise, it is safe bet to assume that entire industry is just out to get you. You can always find exceptions but those are indeed the exceptions.

Jags4186
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Re: Premium gas at BJ's for Mercedes

Post by Jags4186 » Thu Jan 18, 2018 1:14 pm

Oh please. The check engine light is on because you bought an expensive car that has lots of fancy electrical parts that can break. BJs sells millions of gallons of gas a year. If they were selling crap there would be lawsuits.

I bought a Honda Civic LX. The check engine light came on a bunch of times. Turns out the O2 sensor was faulty. They replaced it under warranty. Now it never comes on.

I'd let the Mercedes dealership start replacing things under warranty until its fixed not accept a "don't buy gas from BJs" excuse.

rooms222
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Re: Premium gas at BJ's for Mercedes

Post by rooms222 » Thu Jan 18, 2018 1:35 pm

AAA also recommends Top Tier gas. The full research report is a link on this press release page. http://newsroom.aaa.com/2016/07/aaa-not ... ted-equal/

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 1:41 pm

Jags4186 wrote:
Thu Jan 18, 2018 1:14 pm
Oh please. The check engine light is on because you bought an expensive car that has lots of fancy electrical parts that can break. BJs sells millions of gallons of gas a year. If they were selling crap there would be lawsuits.

I bought a Honda Civic LX. The check engine light came on a bunch of times. Turns out the O2 sensor was faulty. They replaced it under warranty. Now it never comes on.

I'd let the Mercedes dealership start replacing things under warranty until its fixed not accept a "don't buy gas from BJs" excuse.
If fact, when I brought the car in the rep reminded me that there are "100 computers on this vehicle" as compared to the 20 computers on my C300 2011. We asked him why this is happening to a new car. He replied by reminding us that these things happen with so much technology.
I doubt very much we'll be changing the premium gas. Thanks for the sober reply

TBillT
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Re: Premium gas at BJ's for Mercedes

Post by TBillT » Thu Jan 18, 2018 1:49 pm

Here is the American Petroleum Institute map of Gasoline requirements. Southwest Maine on the coast would appear to be reformulated gasoline. I was having trouble visualizing how western Maine is on the coast, but OK now I see.

http://www.api.org/~/media/Files/Policy ... ts-Map.pdf

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wander
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Re: Premium gas at BJ's for Mercedes

Post by wander » Thu Jan 18, 2018 1:57 pm

I have been filling up gas at BJs. Never had a problem.

Spirit Rider
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Re: Premium gas at BJ's for Mercedes

Post by Spirit Rider » Thu Jan 18, 2018 2:35 pm

Rupert wrote:
Thu Jan 18, 2018 12:33 pm
She said, for what it's worth, that the discount chains buy gas from them after it has been sitting in their holding tanks for a while. The longer it sits in those holding tanks before being transferred to a tanker truck for delivery, the more condensation occurs. That's why the distributor sells it at a discount.
Sounds like BS FUD to me. Unless they operate very different than the terminals around here. All the gas is the same and the only difference is the additives. Sounds like someone not in the know is playing a game of telephone

Rupert
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Re: Premium gas at BJ's for Mercedes

Post by Rupert » Thu Jan 18, 2018 2:54 pm

Spirit Rider wrote:
Thu Jan 18, 2018 2:35 pm
Rupert wrote:
Thu Jan 18, 2018 12:33 pm
She said, for what it's worth, that the discount chains buy gas from them after it has been sitting in their holding tanks for a while. The longer it sits in those holding tanks before being transferred to a tanker truck for delivery, the more condensation occurs. That's why the distributor sells it at a discount.
Sounds like BS FUD to me. Unless they operate very different than the terminals around here. All the gas is the same and the only difference is the additives. Sounds like someone not in the know is playing a game of telephone
Yes, all the gas is the same in the sense it all comes from the same refinery and is delivered by the same tanker ship. The discount stores just buy it after it's been sitting in the distributor's tanks longer. How much longer I don't know. I'm just telling you what she said. She's their in-house accountant so certainly knows what the various chains are paying for the gas. Are you disputing the condensation principle? And what's "FUD"?

Spirit Rider
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Re: Premium gas at BJ's for Mercedes

Post by Spirit Rider » Thu Jan 18, 2018 3:27 pm

Rupert wrote:
Thu Jan 18, 2018 2:54 pm
Yes, all the gas is the same in the sense it all comes from the same refinery and is delivered by the same tanker ship. The discount stores just buy it after it's been sitting in the distributor's tanks longer. How much longer I don't know. I'm just telling you what she said. She's their in-house accountant so certainly knows what the various chains are paying for the gas. Are you disputing the condensation principle? And what's "FUD"?
FUD = Fear, Uncertainty and Doubt. Usually used as a way to diminish the competitive product, ideas, etc...

I don't discount the effects of condensation. I just question the veracity of what is likely multiple-hand hearsay.

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 4:58 pm

Spirit Rider wrote:
Thu Jan 18, 2018 3:27 pm
Rupert wrote:
Thu Jan 18, 2018 2:54 pm
Yes, all the gas is the same in the sense it all comes from the same refinery and is delivered by the same tanker ship. The discount stores just buy it after it's been sitting in the distributor's tanks longer. How much longer I don't know. I'm just telling you what she said. She's their in-house accountant so certainly knows what the various chains are paying for the gas. Are you disputing the condensation principle? And what's "FUD"?
FUD = Fear, Uncertainty and Doubt. Usually used as a way to diminish the competitive product, ideas, etc...

I don't discount the effects of condensation. I just question the veracity of what is likely multiple-hand hearsay.
I certainly agree with the effect of condensation on the gas. Would it not be beneficial to use an additive to the gas periodically to counteract this? Why then does MB not recommend this additive? I know they have additives to buy in the parts dept. If I continue to use BJ's gas, is it not advisable to use an additive? If so, which one? Any ideas on this?

Jags4186
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Re: Premium gas at BJ's for Mercedes

Post by Jags4186 » Thu Jan 18, 2018 5:00 pm

I’ll say for one thing this makes me never want to buy a Mercedes. I like cars that can use gas from every station. Seems to me they would be the better engineered engines...

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 5:36 pm

Jags4186 wrote:
Thu Jan 18, 2018 5:00 pm
I’ll say for one thing this makes me never want to buy a Mercedes. I like cars that can use gas from every station. Seems to me they would be the better engineered engines...
I understand; but, the list of cars requiring premium gas with certain octane rating is ever increasing. This is a problem easily solved. Either I stick with the gas I'm currently using or change to a top tier brand. Perhaps find out about an additive. Not that big a deal to me. As far as not ever buying a MB.....I love this car. It's the best riding car I've ever owned. Having said that, the dealer just called and they need it for a second day to fix all the electronic malfunction notifications. :)

neilpilot
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Re: Premium gas at BJ's for Mercedes

Post by neilpilot » Thu Jan 18, 2018 6:12 pm

dollarsaver wrote:
Thu Jan 18, 2018 4:58 pm
I certainly agree with the effect of condensation on the gas. Would it not be beneficial to use an additive to the gas periodically to counteract this? Why then does MB not recommend this additive? I know they have additives to buy in the parts dept. If I continue to use BJ's gas, is it not advisable to use an additive? If so, which one? Any ideas on this?
Isopropyl alcohol is generally used to "dry gas". It's designed to prevent moisture in the gas from crystalizing out in cold temperatures, and so it doesn't actually remove the moisture but binds with it. Commercially, it's available as Iso-HEET. Note that this is 99% alcohol, and comes in a red bottle. The same company markets an inferior additive, that already contains some water, called HEET in a yellow bottle.

I sometimes add a bottle of Iso-HEET to each of my 2 aircraft gas tanks if I plan on flying high in very cold weather, since otherwise ice crystals can clog the fuel filter and stop the engine.

johnubc
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Re: Premium gas at BJ's for Mercedes

Post by johnubc » Thu Jan 18, 2018 6:37 pm

Gernerally, there is nothing wrong with gas from BJ's or any other station. However, certain stations could have an issue if there are leaks in their tanks allowing water to contaminate the fuel. A general 'don't buy BJ's gas' from a technician - advice I would ignore.

all of the gas is processed the same way, blended and distributed - it is all the same. Name brands do add additives and detergents -and a marketing scheme called Top Tier is one that is all the same - http://www.toptiergas.com/licensedbrands/ - kinda like an Idaho Potato - Russet Potato's cannot be called an Idaho Potato, but an Idaho Potato can be called a Russet.

Spirit Rider
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Re: Premium gas at BJ's for Mercedes

Post by Spirit Rider » Thu Jan 18, 2018 7:11 pm

Jags4186 wrote:
Thu Jan 18, 2018 5:00 pm
I’ll say for one thing this makes me never want to buy a Mercedes. I like cars that can use gas from every station. Seems to me they would be the better engineered engines..
This is not an issue unique to Mercedes. Many automobile manufactures now advise the use top tier gasoline. In fact this can be the result of far superior engineered engines.

0W40 synthetic motor oil is far more expensive than 10W40 conventional oil. Which one do you think is necessary for the most advanced engine technology.

It is rather ironic that I am defending top tier gasoline recommendations when for the most part I do not use it. My manufacturer does not see the need to recommend it for my engine. So I just use a fuel system cleaner occasionally.

fishboat
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Re: Premium gas at BJ's for Mercedes

Post by fishboat » Thu Jan 18, 2018 7:40 pm

hmmm...I'm not buying some of the theory here...

I'm a retired chemist, though not from the petroleum-refining industry.

Doubt #1:

What Neil said just above is how it works. While ethanol is added to gasoline for a number of reasons..a political & somewhat practical topic much beyond what's being discussed here..dry ethanol (or isopropanol) added to gasoline will tend to bring the water into solution, make water miscible, with the gas (the hydrophilic aspects of alcohol bind with water while the hydrophobic aspects of alcohol pull it into solution with the hydrophobic gasoline).

That being the case, RFG "ethanol added up to 10%" gasoline will carry more water in solution before a two phase mixture happens. Claims of water continuing to condense in the gas stations tanks, and accumulating...aahh..I don't think it's happening.

Q: Where does the new water come from?
A: The air.

Q: When does water vapor in air condense into liquid water?
A: When the dew point is reached.

The gas station tanks are vented to the atmosphere. As gas is pumped out and into cars, air is pulled into the storage tanks. That air may be warmer than the storage tank gas & tank walls(it wouldn't in the wintertime). That warmer air will contain water such that some condensation happens after entering the tank. However the 10% ethanol gas will tend to absorb that water. Gas stations turn over their inventory fairly fast..thus introducing fresh, dry(er) gas to the storage tanks and this continually pulls water out of the tank. Water will only accumulate in the storage tank if the volume of condensate exceeds what the fresh ethanol-gasoline is removing. I doubt it accumulates. I could be wrong. Anyone have a reference on the accumulation?

Doubt #2

Gas stations, the end-use customers of gas-refinery distribution, doing the final, proprietary additive formulation that makes Sunoco gas, Sunoco gas, or Chevron gas, Chevron gas?

I doubt it.

The additives will be mostly, or completely flammable materials. There will be a number of compounds in the additive. Handling flammable materials, particularly in public, is a highly regulated activity. Given the typical highly educated work staff at gas stations, I'm thinking this "additive addition" must be automated. This, in turn, means each gas station either has a separate additive storage tank and delivered gas-dosing equipment, followed by a recirc agitation system(and all of that requires maintenance and duplicates, thousands of times, a single bulk refinery batching plant), OR, each fresh gas delivery truck is adding the additive package when he delivers the gas...that ain't happening. None of this is happening. It's far too redundant and expensive, and impossible to regulate, let alone control quality. Liability would be MUCH too high.

Proprietary gas is ordered upstream at the refinery or post-refinery-formulator where additive are brought in by rail and stored in bulk. A Chevron station orders Chevron gas..it's made in very large batches and shipped to a distributor..then shipped to a local gas station.

fishboat
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Re: Premium gas at BJ's for Mercedes

Post by fishboat » Thu Jan 18, 2018 7:48 pm

duplicate..

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Ged
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Re: Premium gas at BJ's for Mercedes

Post by Ged » Thu Jan 18, 2018 8:30 pm

fishboat wrote:
Thu Jan 18, 2018 7:40 pm

The additives will be mostly, or completely flammable materials. There will be a number of compounds in the additive. Handling flammable materials, particularly in public, is a highly regulated activity. Given the typical highly educated work staff at gas stations, I'm thinking this "additive addition" must be automated. This, in turn, means each gas station either has a separate additive storage tank and delivered gas-dosing equipment, followed by a recirc agitation system(and all of that requires maintenance and duplicates, thousands of times, a single bulk refinery batching plant), OR, each fresh gas delivery truck is adding the additive package when he delivers the gas...that ain't happening. None of this is happening. It's far too redundant and expensive, and impossible to regulate, let alone control quality. Liability would be MUCH too high.

Proprietary gas is ordered upstream at the refinery or post-refinery-formulator where additive are brought in by rail and stored in bulk. A Chevron station orders Chevron gas..it's made in very large batches and shipped to a distributor..then shipped to a local gas station.
Retired chemical engineer here.

1. Gas stations by definition handle flammable materials in bulk and are permitted accordingly. Additional handling of a minor flammable additive would not affect the permitting or risk profile significantly. The issue is quality control, not safety or permitting.

2. The idea of each gasoline brand requiring its own distributor infrastructure is economically bonkers. The additives are blended into the gasoline as part of the tanker fill process. Modern CPI metering equipment, control systems and instrumentation is easily up to this task. This is confirmed by the AAA report on gas quality.

"Base gasoline (fuel without additives) from various refineries is usually stored in common tanks at the
distribution terminal until a retail gas station places an order for the product. This is when the individual
brands are created through the addition of proprietary additive packages. As a tanker truck is being
filled at the terminal, base gasoline is blended with a detergent additive package specific to that retailer."

https://www.sinclairoil.com/sites/defau ... INAL-1.pdf

As far as water accumulation goes, this is a far more complex problem than you might imagine just thinking about it casually. For example the removal of lead from gasoline means microorganisms can grow in fuel storage tanks.

This gives an introduction to the topic:

https://www.steeltank.com/Portals/0/pub ... %20_2_.pdf

dollarsaver
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Re: Premium gas at BJ's for Mercedes

Post by dollarsaver » Thu Jan 18, 2018 8:54 pm

OK. This is getting informative but way to nerdy for me.
Assumption: If I continue to get premium gas at BJ's.....$2.75/gallon for my MB.....see question below:

Question: What can I add (periodically) to the tank to keep the moving parts from collecting carbon deposits? Please be as specific as you can.

fishboat
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Re: Premium gas at BJ's for Mercedes

Post by fishboat » Thu Jan 18, 2018 9:01 pm

Ged wrote:
Thu Jan 18, 2018 8:30 pm

Retired chemical engineer here.

1. Gas stations by definition handle flammable materials in bulk and are permitted accordingly. Additional handling of a minor flammable additive would not affect the permitting or risk profile significantly. The issue is quality control, not safety or permitting.

2. The idea of each gasoline brand requiring its own distributor infrastructure is economically bonkers. The additives are blended into the gasoline as part of the tanker fill process. Modern CPI metering equipment, control systems and instrumentation is easily up to this task. This is confirmed by the AAA report on gas quality.

"Base gasoline (fuel without additives) from various refineries is usually stored in common tanks at the
distribution terminal until a retail gas station places an order for the product. This is when the individual
brands are created through the addition of proprietary additive packages. As a tanker truck is being
filled at the terminal, base gasoline is blended with a detergent additive package specific to that retailer."

https://www.sinclairoil.com/sites/defau ... INAL-1.pdf

As far as water accumulation goes, this is a far more complex problem than you might imagine just thinking about it casually. For example the removal of lead from gasoline means microorganisms can grow in fuel storage tanks.

This gives an introduction to the topic:

https://www.steeltank.com/Portals/0/pub ... %20_2_.pdf
We're in agreement. I worked in a chemical (solvent-high temp polymer manufacturing) batch & continuous processing plant for nearly 30 years. Your additive package to base stock at the terminal is how I imagined it would work..the intent of my description.

As for #1..the gas stations are license to do what they do..hold and pump gas. I don't doubt that any formulation/additive batching on premise would require a whole other set of regulations, air permit assessment.. etc as it's a separate process. Doesn't matter..not worth debating..it isn't done anyway.

Teague
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Re: Premium gas at BJ's for Mercedes

Post by Teague » Thu Jan 18, 2018 9:34 pm

As for #1..the gas stations are license to do what they do..hold and pump gas. I don't doubt that any formulation/additive batching on premise would require a whole other set of regulations, air permit assessment.. etc as it's a separate process. Doesn't matter..not worth debating..it isn't done anyway.
Apparently Costco does mix their additive package on-site as the fuel is dispensed.

http://www.costcoconnection.com/connect ... pg=37#pg37
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BolderBoy
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Re: Premium gas at BJ's for Mercedes

Post by BolderBoy » Fri Jan 19, 2018 3:14 pm

Teague wrote:
Thu Jan 18, 2018 9:34 pm
As for #1..the gas stations are license to do what they do..hold and pump gas. I don't doubt that any formulation/additive batching on premise would require a whole other set of regulations, air permit assessment.. etc as it's a separate process. Doesn't matter..not worth debating..it isn't done anyway.
Apparently Costco does mix their additive package on-site as the fuel is dispensed.

http://www.costcoconnection.com/connect ... pg=37#pg37
The article says, "as the fuel is delivered.", which would make more sense than while I'm putting it into my vehicle.

Thanks for the link. My Costco Connection goes straight from the mailbox into recycle.
"Never underestimate one's capacity to overestimate one's abilities" - The Dunning-Kruger Effect

tbradnc
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Re: Premium gas at BJ's for Mercedes

Post by tbradnc » Sun Jan 21, 2018 7:26 pm

neilpilot wrote:
Thu Jan 18, 2018 6:12 pm
dollarsaver wrote:
Thu Jan 18, 2018 4:58 pm
I certainly agree with the effect of condensation on the gas. Would it not be beneficial to use an additive to the gas periodically to counteract this? Why then does MB not recommend this additive? I know they have additives to buy in the parts dept. If I continue to use BJ's gas, is it not advisable to use an additive? If so, which one? Any ideas on this?
Isopropyl alcohol is generally used to "dry gas". It's designed to prevent moisture in the gas from crystalizing out in cold temperatures, and so it doesn't actually remove the moisture but binds with it. Commercially, it's available as Iso-HEET. Note that this is 99% alcohol, and comes in a red bottle. The same company markets an inferior additive, that already contains some water, called HEET in a yellow bottle.

I sometimes add a bottle of Iso-HEET to each of my 2 aircraft gas tanks if I plan on flying high in very cold weather, since otherwise ice crystals can clog the fuel filter and stop the engine.
Trivia fact. Yellow HEET makes a great fuel for hiking/backpacking alcohol stoves. Red HEET makes too much smoke.

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