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Aux fuel tank

H3LZSN1P3R

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I have a 91 gallon tank! It costs a kidney to fill
I have 94 gallons i understand that! Here its about 1.15 per L (4.4375$/gal) its is about a 400$ fuel up if i let it get to the fuel light lol empty would be 20$ more lol
 

RossT

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Here's my set up. ATI 41 gallon tank with a 38gph pump wired to an aux switch. 91 gallons.


EDIT: this is the third truck I've rigged like this. Keeps thieves and nosey highway patrol at bay... LOL

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Sent from my moto z4 using Tapatalk
 

powersglp

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So I have a 2020 ram 2500. I have a 50gal aux tank that i an gravity feeding using the rds gravity feed kit. My problem is it will only feed like 1/4 to 1/2 the tank and will just stop gravity feeding. Truck will burn through the rest of the fuel in the tank but the aux tank will still be half full and not drain the rest of the way in.
 

Metternacht

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Just asking as I don’t have any experience with gravity feed but is there a possibility of the Aux tank developing a vacuum that is preventing the tank from draining?
 

powersglp

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Dont think so. Cause it will not drain on down regardless of how it is vented sealed or anything
 

RV_Goose

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My understanding was that a gravity flow auxiliary fuel tank is not recommended and prone to leaking and overflowing. I have installed in my 2019 Ram 2500 Cummins Diesel short bed a Titan 40 gal Auxiliary Fuel Tank. It automatically pumps fuel from the top of the tank into the vehicles main tank. There are a range of tank size and placement options.
It the experience myself of 6 friends I have with gravity aux tanks.
 

H3LZSN1P3R

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So I have a 2020 ram 2500. I have a 50gal aux tank that i an gravity feeding using the rds gravity feed kit. My problem is it will only feed like 1/4 to 1/2 the tank and will just stop gravity feeding. Truck will burn through the rest of the fuel in the tank but the aux tank will still be half full and not drain the rest of the way in.
If you have the rubber hose that came with the kit toss it and get some good quality fuel line… the fuel line that came with my kit was collapsed and would kink easy so i could see if your tank having less fuel it cant push the fuel past the collapsed/slightly kinked hose
 

SMK Shoe

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If it partially feeding into the mail tank, it can only be two things and both have been mentioned. Either a fuel line that is partially kinked, so when the fuel level is low there is not enough pressure to push ( not probable) and the highly probable is that the check valve is blocked and as fuel is draining causing a vacuum in the tank. Once it stops draining, loosen the filler cap and see if it starts to drain again
 

H3LZSN1P3R

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If it partially feeding into the mail tank, it can only be two things and both have been mentioned. Either a fuel line that is partially kinked, so when the fuel level is low there is not enough pressure to push ( not probable) and the highly probable is that the check valve is blocked and as fuel is draining causing a vacuum in the tank. Once it stops draining, loosen the filler cap and see if it starts to drain again
You would not be able to fill the oem tank if the oem tank vent was blocked also the float would remain open if the tank was having a vacuum effect
 

SMK Shoe

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I was talking about the Aux tank not draining fully. I have a 45 gallon RDS and had the vent line routed between the tank and toolbox. Had a little bit of a kink and drained Sloooooow. Re routed it and now it drains about a gallon every 8 miles. DTE stays just about even. Once DTE starts to drop, Aux tank empty. ( I usually open the valve from the Aux tank at about 1/2 tank on OEM )
 

H3LZSN1P3R

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I was talking about the Aux tank not draining fully. I have a 45 gallon RDS and had the vent line routed between the tank and toolbox. Had a little bit of a kink and drained Sloooooow. Re routed it and now it drains about a gallon every 8 miles. DTE stays just about even. Once DTE starts to drop, Aux tank empty. ( I usually open the valve from the Aux tank at about 1/2 tank on OEM )
He did mention that does not seem to be the issue… I just leave mine open all the time on my 100 gal that way i get a surprise when the fuel gauge starts to move after a long time lol
 

SMK Shoe

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Having the Aux tank's is nice. Only thing that sux is at the end of the day when the 45 is empty and 50 gallon OEM is down to a 1/4. Really hurts the wallet doing 60-75 gallons a day.
 

H3LZSN1P3R

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Having the Aux tank's is nice. Only thing that sux is at the end of the day when the 45 is empty and 50 gallon OEM is down to a 1/4. Really hurts the wallet doing 60-75 gallons a day.
Yea it costs me 650$ to fill both my 100gal and the oem 32gal it is really painful lol
 

Rappr

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So I have a 2020 ram 2500. I have a 50gal aux tank that i an gravity feeding using the rds gravity feed kit. My problem is it will only feed like 1/4 to 1/2 the tank and will just stop gravity feeding. Truck will burn through the rest of the fuel in the tank but the aux tank will still be half full and not drain the rest of the way in.
More than likely the little vent hose where the roll over vent valve is, has a mud dauber nest in it. I ended up putting a screen over the hose opening.
To check, when you see that it isn’t feeding into your mains, open the fuel cap. It should NOT have a vacuum.
 

bikabill

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He did mention that does not seem to be the issue… I just leave mine open all the time on my 100 gal that way i get a surprise when the fuel gauge starts to move after a long time lol
"...leave mine open all the time..." Do you have the DTE gauge and not get an error/check engine warning?

I just had an RDS 60 gallon tank, gravity feed, installed in my 2021 Ram. I haven't tried leaving it open while driving, but I just tried to fill the OEM tank from the aux tank, and the OEM tank builds up pressure and stops filling until I push the OEM flap. Then air poofs out and it starts filling again. So I'm guessing if I fill while driving it will work better(?). But I've heard that with the DTE gauge I'll get an error message. I'm also thinking so what if I get an error message... just clear it out with five starts, right?
 

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