Fuel Tanker Driver Here

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271
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Northeast Georgia
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Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
 
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D/FW Metroplex
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
As disconcerting as that is, it does tend to explain some poor performing results I have been seeing in my datalogs lately. I guess I'll just have to stake out my favorite spots and watch for the fuel trucks before buying my gas. laugh Thanks again for the info! Nuke
 
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5,242
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San Francisco Bay Area
Originally Posted by The_Nuke
I am curious about the concept of stale gasoline though. Can you explain (to the best of your knowledge) what it means to have gasoline go stale? Does it behave differently from fresh gasoline when burned in the intended scenarios? What kind of time frame is there before gasoline goes stale while sitting in the storage tanks waiting to be sold?
Gasoline certainly oxidizes and degrades, but it really depends on where it is. A modern car's fuel system is pressurized with fuel vapor so there's not as much oxidation as with a gas can. And these days there are fancy gas cans.
 
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664
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New Jersey
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
 

Deo

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14
Location
Atlanta, GA USA
I thought this additive treat rate chart was interesting - found it on the Magellan Midstream site. It explains why companies like Shell and Exxon are able to promote superior qualities of their premium-grade fuels (higher additive %) versus regular-grade (lower additive %). Even though the same exact additive is being used across all octane levels. [Linked Image]
 
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251
Location
Bowling Green, OH
Originally Posted by painfx
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
Old mechanics tale. Modern gas dispensers have a fuel filter for each grade. Usually 5, 10, or 30 microns media.
 
Messages
271
Location
Northeast Georgia
Thread starter
Originally Posted by painfx
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
Here's a big wrench in the theory. A few stores may only get a delivery once or twice a week. However, MOST accounts get a delivery every day....some as many as 3 loads per day. When would the sediment have time to 'settle' in these high volume stores? Another thing to think about...whenever you buy gas, how do you know a fuel tanker didn't just leave just a few minutes before you got there? Keith is correct. The retail pump's filter likely filters as good or better than the filter in your vehicle. Between that filter and your vehicle's filter, you should have some pretty clean fuel getting injected into the engine.
 
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271
Location
Northeast Georgia
Thread starter
Originally Posted by Deo
I thought this additive treat rate chart was interesting - found it on the Magellan Midstream site. It explains why companies like Shell and Exxon are able to promote superior qualities of their premium-grade fuels (higher additive %) versus regular-grade (lower additive %). Even though the same exact additive is being used across all octane levels. [Linked Image]
Good find. Pretty much confirms what the terminal operator explained to me about the higher ratio additive in premium gas.
 
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2,091
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Ottumwa, Iowa
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Sometimes gas sits for several months in tanks at terminals before it gets delivered to stations due to various reasons. Sometimes the refineries have to ship an out of season RVP to make room. It gets parked in a tank till it is time to use it.
 
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5,242
Location
San Francisco Bay Area
Originally Posted by painfx
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
The only gas station I think might cause concern while it's refueling is Costco. That's primarily because they're relying on splash blending in the tank during the delivery. I figure properly blended fuel mixed with properly blended fuel should be fine, but they have concentrated detergent additive added first - that needs to be agitated by the incoming fuel. But maybe they use alternating tanks. A place with as high a volume as Costco could certainly do that. But yeah others noted that all fuel stations use various filters. The one that is most noticeable would be water filters, which still work when saturated but will really slow down the flow.
 
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5,242
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San Francisco Bay Area
Originally Posted by jhellwig
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Sometimes gas sits for several months in tanks at terminals before it gets delivered to stations due to various reasons. Sometimes the refineries have to ship an out of season RVP to make room. It gets parked in a tank till it is time to use it.
There are all sorts of things. There's the transport time through pipelines. Some gasoline is shipped by rail or even by tanker ships across an ocean. There are isolated islands around the world that don't have refineries, so they get finished gasoline shipped by tanker.
 
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13,343
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1/2 hr N.E. of Detroit
Originally Posted by painfx
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
I never pump gas with the tanker on premise. Also, no one knows if the filter is clogged, or has minimum filtering abilities. I also never pump with the engine running. Besides electrical field danger, today's gas pumps deliver gas at fast speeds ad that stirs the bottom of our tanks. Every time I pump gas in my 04' Colorado with the engine running, my engine begins to stutter /miss and it's seen nothing but Mobil/Exxon, BP or Shell top-tiers, it's entire lifetime and never filled with less than a quarter-tank.... and it's gas filter is the largest I've ever seen and changed every 60K.. Don't pump with tankers there and don't pump with engine running.
 
Last edited:
Messages
1,271
Location
FL
Originally Posted by Triple_Se7en
Originally Posted by painfx
Originally Posted by GoldDot40
Any gasoline that's over 30 days old will begin to degrade. It will lose combustibility and volatility. Chemical reactions occur and varnish begins to form. NO gasoline that hasn't had an additive mixed with it to slow down the process is immune. Pure gas will "go stale" just like oxygenated/blended gas. You will do yourself a favor by purchasing from a higher volume retailer.
Is it unwise to pump gas while they are refilling the tanks with new gas? I heard it disturbs the tank and sedements gets mixed up. Or is it better to wait until next day to refill?
I never pump gas with the tanker on premise. Also, no one knows if the filter is clogged, or has minimum filtering abilities. I also never pump with the engine running. Besides electrical field danger, today's gas pumps deliver gas at fast speeds ad that stirs the bottom of our tanks. Every time I pump gas in my 04' Colorado with the engine running, my engine begins to stutter /miss and it's seen nothing but Mobil/Exxon, BP or Shell top-tiers, it's entire lifetime and never filled with less than a quarter-tank.... and it's gas filter is the largest I've ever seen and changed every 60K.. Don't pump with tankers there and don't pump with engine running.
If you don't pump with the tanker there you would never be able to get gas at my local Costco ...... Personally as an ex fuel truck driver, I think the issue is way overblown
 
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On another site
GoldDot40, thanks much for the fantastic info! I don't know how I have missed this gem of a thread for so long.
Originally Posted by GoldDot40
Originally Posted by Deo
I thought this additive treat rate chart was interesting - found it on the Magellan Midstream site. It explains why companies like Shell and Exxon are able to promote superior qualities of their premium-grade fuels (higher additive %) versus regular-grade (lower additive %). Even though the same exact additive is being used across all octane levels. [Linked Image]
Good find. Pretty much confirms what the terminal operator explained to me about the higher ratio additive in premium gas.
So it seems like the "use our premium fuel for 2000 miles for better mpg and performance" advertising may be true?
 
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93
Location
Destrehan, LA
So I read about how base gasoline is 84 octane blended with ethanol to make 87 but what about the "pure gas" or "non-ethanol" fuels that are frequent around my area (New Orleans) Most non ethanol stations will carry 87 octane and 91 octane. 10-15 years ago you could find 93 octane pure gas but I haven't seen any in a long time. When a RaceTrac station opened up in Hahnville, LA they offered 85 octane non ethanol fuel. I emailed the Corperate headquarters basically asking "[censored] this isn't Colorado" and the 85 octane stickers were quickly replaced with 87. So basically, what I'm asking is, what's the nitty gritty on all this non-ethanol business.
 
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5,242
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San Francisco Bay Area
Originally Posted by asleepz
So I read about how base gasoline is 84 octane blended with ethanol to make 87 but what about the "pure gas" or "non-ethanol" fuels that are frequent around my area (New Orleans) Most non ethanol stations will carry 87 octane and 91 octane. 10-15 years ago you could find 93 octane pure gas but I haven't seen any in a long time. When a RaceTrac station opened up in Hahnville, LA they offered 85 octane non ethanol fuel. I emailed the Corperate headquarters basically asking "[censored] this isn't Colorado" and the 85 octane stickers were quickly replaced with 87. So basically, what I'm asking is, what's the nitty gritty on all this non-ethanol business.
It's possible to make fuel without ethanol. It just requires a higher octane rating base fuel. However, the majority of the base fuel sold in the US is mean to be blended with ethanol. It's not just a mandate but that it helps boost octane rating. Ethanol or MTBE has an extremely high blending octane rating. 10% of fuel grade ethanol will boost most gasoline more than 2 AKI points. E85 has an AKI octane rating of 100 to 105. Once that's used in most Flex Fuel engines, it does some crazy stuff to extract more energy than would be expected via the theoretical energy content.
 
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5,242
Location
San Francisco Bay Area
Originally Posted by Deo
I thought this additive treat rate chart was interesting - found it on the Magellan Midstream site. It explains why companies like Shell and Exxon are able to promote superior qualities of their premium-grade fuels (higher additive %) versus regular-grade (lower additive %). Even though the same exact additive is being used across all octane levels. [Linked Image]
Keropur is BASF's brand name. There are 15 different versions of Keropur 205. https://www3.epa.gov/otaq/fuels1/ffars/web-gas.htm Most pipeline/terminal operators offer a "generic" additive and I suppose give the customer the option of how much to add. A lot of independent gas stations will just take that and call it a day. Way back before Valero went Top Tier they claimed that they simply used whatever generic additive was available at a particular terminal. But certain brands require that their franchise stations use their specific additives, although there's really nothing that prevents a fuel marketer like Phillips 66 from purchasing an off the shelf additive that meets the Top Tier requirement. Costco commissioned Lubrizol to make a custom additive just for them.
 
Messages
251
Location
Bowling Green, OH
Originally Posted by asleepz
So I read about how base gasoline is 84 octane blended with ethanol to make 87 but what about the "pure gas" or "non-ethanol" fuels that are frequent around my area (New Orleans) Most non ethanol stations will carry 87 octane and 91 octane. 10-15 years ago you could find 93 octane pure gas but I haven't seen any in a long time. When a RaceTrac station opened up in Hahnville, LA they offered 85 octane non ethanol fuel. I emailed the Corperate headquarters basically asking "[censored] this isn't Colorado" and the 85 octane stickers were quickly replaced with 87. So basically, what I'm asking is, what's the nitty gritty on all this non-ethanol business.
They blend 84 E0 with 91 E0 to get 87 E0 and 89 E0 at the terminal.
 
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