Planning out my 30 gallon in-bed auxiliary fuel tank for my 7.3L Tremor

UTEngineer

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ATI makes an aluminum auxiliary 30 gallon gasoline tank that I would like to put in the front of the bed of my F250 7.3L Tremor.


Before you give me crap on selecting the smallest 30 gallon auxiliary tank option, this tank size fits perfectly under my Bak Box Toolbox and Backflip folding bed cover, and also takes up the least amount of room in the front of the pickup box as well. Plus, 64 gallons of gas (stock + auxiliary) gets us the maximum distance our kids will travel towing our travel trailer in one day anyway (~ 500 miles or 7 hours on the highway).

Need some help verifying / planning out a few items regarding the installation.

1. Is the 7.3 factory fill line a standard 1 inch inside diameter for the optional 1 inch fill neck adapter to fit correctly ?

2. What is the inside diameter of the 7.3 factory tank vent line so I can purchase the proper “T“ adapter to plumb the auxiliary tank vent into the factory tank vent line and close the ventilation loop to ensure I don't get a check engine / loose gas cap indication on the dash ?

3. Any recommendations on a similar yet quieter in-line fuel pump than the Airtex E84070 recommended by the tank manufacturer ?
 
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Modman

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That is an interesting option... I have considered something similar but not sure if I want to give up the floor space. I am not a point where I am towing on a regular basis so have time to decide.

I see from their website this tank is Title 49 compliant. I would not even begin to say I understand the whole 900 page document but this is a good summary/excerpt of the liquid fuel tank portion:


Some manufacturers are upfront with their compliance, some are not, from what I have found. I will watch this thread.

I was researching the same and found the following:
1. 1" ID on the funnel side
2. 1/4" ID, 5/16" OD
3. ? Curious to find out though!
 

OldCowboy

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I thought you can only have a gravity fed tank on a diesel. Now I see there is a pump in the feed line but the tank is still above the factory tank. That should make it gravity fed. I didn't think they would let you open the fill pipe on a gas system.
 

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It pumps out the top of the tank and has it's own vent so would not qualify as a gravity. This essentially makes it no different than filling your factory tank from the pump.

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Definitely going to follow this one. I'm hoping Ford just addresses the issue and allows a larger tank, even if it's just an upcharge option. At least give us the option to lose a little ground clearance for the bigger tank.
 
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That is an interesting option... I have considered something similar but not sure if I want to give up the floor space. I am not a point where I am towing on a regular basis so have time to decide.

I see from their website this tank is Title 49 compliant. I would not even begin to say I understand the whole 900 page document but this is a good summary/excerpt of the liquid fuel tank portion:


Some manufacturers are upfront with their compliance, some are not, from what I have found. I will watch this thread.

I was researching the same and found the following:
1. 1" ID on the funnel side
2. 1/4" ID, 5/16" OD
3. ? Curious to find out though!
Appreciate the response and the factory tank fill and vent line sizing information.

Like you I have not spent the time to thoroughly read the CFR text on gasoline tank restrictions … not sure if I will since the tank is Title 49 compliant.

Really wish a company like Transfer Flow would offer an auxiliary tank system with all the required pieces and parts … or even better … a 60+ gallon replacement gas tank for under the truck.

Not that I have not done projects like this before … but this is my daily driver and it always seems the appropriate parts for a clean installation have to be ordered online since they are not available locally.

Last hurdle, the Ford dealer and warranty denial considerations. Just got done with a long legal battle with GM and the local dealer regarding a transfer case vibration that was caused by a sprocket alignment issue during assembly on my 2019 Duramax. GM and the local dealer denied warranty coverage due to the 4 inch Cognito differential drop lift kit on the truck. After a three year battle I ended up winning the warranty coverage, but the long drawn out experience caused my wife to tell me no more modifications to my trucks until they are off warranty.

So I am headed to talk to the service manager at the local Ford dealership and feel out his stance on plumbing in the auxiliary fuel tank to the factory fill and vent lines. For example, if I have a fuel pump failure while under warranty coverage, are they going to deny warranty coverage because of the auxiliary tank system.

Anyway, will let you know the local Ford service manager’s response and if I decide to move forward on this auxiliary tank system.
 

maxspongebob

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Appreciate the response and the factory tank fill and vent line sizing information.

Like you I have not spent the time to thoroughly read the CFR text on gasoline tank restrictions … not sure if I will since the tank is Title 49 compliant.

Really wish a company like Transfer Flow would offer an auxiliary tank system with all the required pieces and parts … or even better … a 60+ gallon replacement gas tank for under the truck.

Not that I have not done projects like this before … but this is my daily driver and it always seems the appropriate parts for a clean installation have to be ordered online since they are not available locally.

Last hurdle, the Ford dealer and warranty denial considerations. Just got done with a long legal battle with GM and the local dealer regarding a transfer case vibration that was caused by a sprocket alignment issue during assembly on my 2019 Duramax. GM and the local dealer denied warranty coverage due to the 4 inch Cognito differential drop lift kit on the truck. After a three year battle I ended up winning the warranty coverage, but the long drawn out experience caused my wife to tell me no more modifications to my trucks until they are off warranty.

So I am headed to talk to the service manager at the local Ford dealership and feel out his stance on plumbing in the auxiliary fuel tank to the factory fill and vent lines. For example, if I have a fuel pump failure while under warranty coverage, are they going to deny warranty coverage because of the auxiliary tank system.

Anyway, will let you know the local Ford service manager’s response and if I decide to move forward on this auxiliary tank system.
Plumbing in your own solution will probably put you sideways with the law. That is why I went with a transfer tank in my truck. TransferFlow does have a Aux Tank solution that has all the parts required to make it work.
 
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UTEngineer

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Plumbing in your own solution will probably put you sideways with the law. That is why I went with a transfer tank in my truck. TransferFlow does have a Aux Tank solution that has all the parts required to make it work.
Just spoke to Transfer Flow on the phone ... and as I thought ... that is a diesel tank ... not a gasoline tank ... so it will not work for our 7.3L gas Tremors. (told them to add diesel only to the product description)

But thanks for the response and possible solution.
 

Modman

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Just spoke to Transfer Flow on the phone ... and as I thought ... that is a diesel tank ... not a gasoline tank ... so it will not work for our 7.3L gas Tremors. (told them to add diesel only to the product description)

But thanks for the response and possible solution.
It is in there, but I had to hunt for it (see my reply above)... would be nice to say that up front in the description!
 
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Update: Transfer Flow said they have purchased a 7.3L gas Tremor and are currently designing a larger fuel tank to replace the factory gas tank. It will not be released until sometime next year. The extended lead time is due to state & federal government approvals ... most importantly California's CARB certification process ... which will likely be the product release timeline controlling factor. When I inquired about the anticipated tank capacity in gallons, they said it is determined not necessarily on the room underneath the truck ... it may actually be controlled by a per vehicle government emissions restriction regarding the gasoline evaporation rate out of the fuel tank vent line ... i.e. "shedding rate". Leave it to the environmental policy enforcement agencies of the US government to establish these minimal impact control policies regarding fossil fuel automotive emissions.

But if Transfer Flow intends to release a plug and play solution next year for an increased capacity gasoline tank underneath the truck ... I will now be delaying my ambitions to view that product release before moving forward with my "owner-designed" in-bed auxiliary gasoline tank solution.
 
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ccw

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Update: Transfer Flow said they have purchased a 7.3L gas Tremor and are currently designing a larger fuel tank to replace the factory gas tank. It will not be released until sometime next year. The extended lead time is due to state & federal government approvals ... most importantly California's CARB certification process ... which will likely be the product release timeline controlling factor. When I inquired about the anticipated tank capacity in gallons, they said it is determined not necessarily on the room underneath the truck ... it may actually be controlled by a per vehicle government emissions restriction regarding the gasoline evaporation rate out of the fuel tank vent line ... i.e. "shedding rate". Leave it to the environmental policy enforcement agencies of the US government to establish these minimal impact control policies regarding fossil fuel automotive emissions.

But if Transfer Flow intends to release a plug and play solution next year for an increased capacity gasoline tank underneath the truck ... I will now be delaying my ambitions to view that product release before moving forward with my "owner-designed" in-bed auxiliary gasoline tank solution.
That’s a fantastic update on the Transfer Flow replacement tank! You should also post it to this long-running thread on it. Lots of folks watching that thread for updates.

 

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Update: Transfer Flow said they have purchased a 7.3L gas Tremor and are currently designing a larger fuel tank to replace the factory gas tank. It will not be released until sometime next year. The extended lead time is due to state & federal government approvals ... most importantly California's CARB certification process ... which will likely be the product release timeline controlling factor. When I inquired about the anticipated tank capacity in gallons, they said it is determined not necessarily on the room underneath the truck ... it may actually be controlled by a per vehicle government emissions restriction regarding the gasoline evaporation rate out of the fuel tank vent line ... i.e. "shedding rate". Leave it to the environmental policy enforcement agencies of the US government to establish these minimal impact control policies regarding fossil fuel automotive emissions.

But if Transfer Flow intends to release a plug and play solution next year for an increased capacity gasoline tank underneath the truck ... I will now be delaying my ambitions to view that product release before moving forward with my "owner-designed" in-bed auxiliary gasoline tank solution.
That is great news for you. Oddly enough I was looking at 60 gallon tanks today (my Trem is diesel) and I ran across a install video that suggested an in bed would void the warranty. I have no idea if that is true. I also think I read somewhere on a dealer that carries S&B the same thing. I wondered if it was a sales pitch ha I will have to go back and look.
 
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That is great news for you. Oddly enough I was looking at 60 gallon tanks today (my Trem is diesel) and I ran across a install video that suggested an in bed would void the warranty. I have no idea if that is true. I also think I read somewhere on a dealer that carries S&B the same thing. I wondered if it was a sales pitch ha I will have to go back and look.
In my unfortunate experience a good portion of the dealerships are hypocrites and should be considered the enemy. These shady dealers will push aftermarket part or poor installation caused warranty claims onto the manufacturer if you purchased the aftermarket product from them at a ridiculous markup. However, if you purchased a superior aftermarket product elsewhere (which they do not even offer) and receive a superior & cleaner installation elsewhere as well, they will then deny any warranty claim(s) even remotely associated with the aftermarket part or installation, even if it is obviously a manufacturer defect (ex. fuel pump failure), because they make more profit off charging you directly than warranty repair reimbursements from the manufacturer at a discounted rate. So unfortunately we accept the risk that the dealer can and may deny warranty coverage regarding any issue even remotely associated with the larger capacity Transfer Flow replacement fuel tank (which could simply be because you did not purchase and have the product installed by them). For me personally, installing the increased capacity Transfer Flow tank is worth the risk of the warranty violation. However, I mention this issue simply so others can personally evaluate the risk and decide if possibly violating their warranty is worth the increase fuel tank capacity. Cheers.
 
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thevol

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ATI makes an aluminum auxiliary 30 gallon gasoline tank that I would like to put in the front of the bed of my F250 7.3L Tremor.


Before you give me crap on selecting the smallest 30 gallon auxiliary tank option, this tank size fits perfectly under my Bak Box Toolbox and Backflip folding bed cover, and also takes up the least amount of room in the front of the pickup box as well. Plus, 64 gallons of gas (stock + auxiliary) gets us the maximum distance our kids will travel towing our travel trailer in one day anyway (~ 500 miles or 7 hours on the highway).

Need some help verifying / planning out a few items regarding the installation.

1. Is the 7.3 factory fill line a standard 1 inch inside diameter for the optional 1 inch fill neck adapter to fit correctly ?

2. What is the inside diameter of the 7.3 factory tank vent line so I can purchase the proper “T“ adapter to plumb the auxiliary tank vent into the factory tank vent line and close the ventilation loop to ensure I don't get a check engine / loose gas cap indication on the dash ?

3. Any recommendations on a similar yet quieter in-line fuel pump than the Airtex E84070 recommended by the tank manufacturer ?

I thought about going this route but didnt want to tamper with the existing fuel system. Another thing that concerned me was if you accidentally left the transfer pump on or my kid messed with it, there could be an overfill situation...not good with gas especially, or diesel for that matter. Anyway I opted for the ATI 42 gal with a pump on top that i could take in and out in minutes. Also can swap it in a diff truck later, use for diesel, or sell it if they ever make a true replacement tank that I want.
 

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Definitely going to follow this one. I'm hoping Ford just addresses the issue and allows a larger tank, even if it's just an upcharge option. At least give us the option to lose a little ground clearance for the bigger tank.
I have a lot of curosities as to why makers of heavy duty trucks have allowed the aftermarket tank companies to make free money off of their trucks for so long.

If Ford simply offered a 60gal tank and charged $2k for it, people would check that box all the time. It really blows my mind that heavy duty trucks from any of the manufacturers do not have options for a blow molded 119gal tank that fits every nook and cranny under the bed for the guys that buy these things to tow.
 
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I thought about going this route but didnt want to tamper with the existing fuel system. Another thing that concerned me was if you accidentally left the transfer pump on or my kid messed with it, there could be an overfill situation...not good with gas especially, or diesel for that matter. Anyway I opted for the ATI 42 gal with a pump on top that i could take in and out in minutes. Also can swap it in a diff truck later, use for diesel, or sell it if they ever make a true replacement tank that I want.
You hit it right on the head … the overfill issue is my primary concern. Was going to wire the fuel pump into one of my overhead console switches and I would have to watch the truck fuel gauge and shut off the switch when the tank neared the full level. Problem is I have young kids that like to crawl around inside the truck and flip switches … which could easily cause an overfill situation if I am not watching the fuel gauge and do not hear the fuel pump running. That is why I prefer the Transfer Flow solution, which I had in my previous diesel, even if it costs more, because their design has the electronics that tap into the truck’s gas tank level wiring and turns the pump on and off automatically avoiding an overfill situation.
 
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I have a lot of curosities as to why makers of heavy duty trucks have allowed the aftermarket tank companies to make free money off of their trucks for so long.

If Ford simply offered a 60gal tank and charged $2k for it, people would check that box all the time. It really blows my mind that heavy duty trucks from any of the manufacturers do not have options for a blow molded 119gal tank that fits every nook and cranny under the bed for the guys that buy these things to tow.
Unfortunately automobiles in the US today can’t have those high capacity fuel tanks anymore because there are per vehicle emission restrictions regarding the amount of emissions generated thru the gas tank vent line ? Something about results from a sweep test? I have not had time to read up on this, but was told by Transfer Flow that even though there is sufficient room under the truck for a larger tank, that is not necessarily the controlling factor regarding maximum tank capacity, it is actually state and federal government emissions restrictions … go figure.
 

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Unfortunately automobiles in the US today can’t have those high capacity fuel tanks anymore because there are per vehicle emission restrictions regarding the amount of emissions generated thru the gas tank vent line ? Something about results from a sweep test? I have not had time to read up on this, but was told by Transfer Flow that even though there is sufficient room under the truck for a larger tank, that is not necessarily the controlling factor regarding maximum tank capacity, it is actually state and federal government emissions restrictions … go figure.
Good to hear. I just signed for my 2022 and that mod is tops on my list, but I can wait a bit as not losing bed space is a huge plus.

For you guys considering adapting your own, it can be done seamlessly. I imported a diesel tank for my Land Rover LR4 and installed it. Took a little welding and some ingenuity, but it has functioned for years, passed smog and given me zero problems once up and running.
 
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