Aux fuel tank

[H3LZSN1P3R]

"...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?

Sounds like your tank vent is blocked because you should have no issue filling while parked… i have never seen a ram get an error message with the dte gauge i know that any GM will have an issue though

 

[Rappr]

"...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?

I have an RDS

"...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?

I have an RDS 90 gallon gravity feeding into main tank, no codes. BTW, you should not have a vacuum issue. Your main tank or aux tanks breather line is plugged if you do

 

[bikabill]

Not a vacuum issue... actually a pressure issue that builds up in the OEM tank. As long as I hold the OEM flap open, the aux tank drains into the OEM tank.
What year is your Ram? You have the DTE gauge?

 

[Rappr]

Not a vacuum issue... actually a pressure issue that builds up in the OEM tank. As long as I hold the OEM flap open, the aux tank drains into the OEM tank.
What year is your Ram? You have the DTE gauge?

2019 and yes, I have the DTE gauge. The main tank vent shouldn’t allow either pressure nor vacuum to build up in your main tank. I installed the aux tank valve with one end at the main tank rubber boot (I had to cutoff a couple of inches of the metal fill pipe for it to fit).

I believe that little line that runs alongside the main filler pipe is the main tank vent, I would check that first.

 

[bikabill]

Ok, issue resolved. I talked with RDS and was told it is supposed to build up pressure in the OEM tank, that's what stops it from over flowing -- I found that out the hard way, after losing about a gallon while I went in to pay and had installed an aftermarket gas cap which keeps the flapper slightly open. Took of the cap and the flow stopped.

So now I'm going to run like you guys do, just fill the aux tank and keep it flowing all the time.

 

[Burger]

Newbie here and like an idiot I ordered 3500w/ the 32 gal tank. Looking for aux fuel tank/toolbox for dually long bed w/5th wheel hitch and tri-fold tonneau cover. Or cheaper to switch to 50 gal? I think switching will need reprogram, and aux tank will probably void warranty if connected to existing tank? I could be wrong. Any suggestions are much appreciated.

 

[Rappr]

Newbie here and like an idiot I ordered 3500w/ the 32 gal tank. Looking for aux fuel tank/toolbox for dually long bed w/5th wheel hitch and tri-fold tonneau cover. Or cheaper to switch to 50 gal? I think switching will need reprogram, and aux tank will probably void warranty if connected to existing tank? I could be wrong. Any suggestions are much appreciated.

I have a 90 gallon RDS gravity fed aux tank in my 3500 long bed.

I have used the same tank on 3 different trucks. Lets face it at 10MPG towing, the expense of swapping out your 32 gallon tank for 18 more gallons, is cost prohibitive

 

[Linked4door]

I have a 90 gallon RDS gravity fed aux tank in my 3500 long bed.

I have used the same tank on 3 different trucks. Lets face it at 10MPG towing, the expense of swapping out your 32 gallon tank for 18 more gallons, is cost prohibitive

How do you have the vent/rollover valve hooked up? I just picked up a 90gallon RDS last week.

 

[bikabill]

Newbie here and like an idiot I ordered 3500w/ the 32 gal tank. Looking for aux fuel tank/toolbox for dually long bed w/5th wheel hitch and tri-fold tonneau cover. Or cheaper to switch to 50 gal? I think switching will need reprogram, and aux tank will probably void warranty if connected to existing tank? I could be wrong. Any suggestions are much appreciated.

I put a 60 gal RDS aux tank in my 3500 short bed with 5th wheel hitch. All works together just fine. I don't see any way the aux tank can void warranty, it's actually nothing more than putting a load in the truck, and that's what trucks are made for. The gravity feed part of it does require slicing out a few inches of the fill nozzle, but that doesn't affect anything that is normally under warranty.

I'm with Rapper about skip the extra 18 gal and go for the aux tank, lots more bang for the buck. Happy trails!

 

[Rappr]

How do you have the vent/rollover valve hooked up? I just picked up a 90gallon RDS last week.

I ran it through the front left bed stake pocket down between the box. Note: put a piece of screen on the end to keep mud daubers from clogging the hose

 

[RV_Goose]

I wanted to keep my trub bed available for cargo, so I went with a Titan 55 gallon diesel tank to replace the stock 32 gallon on my 2020 RAM 3500 dually. That give me a comfortable 450+ mile range towing my 5th wheel toyhauler.

 

[bikabill]

I wanted to keep my trub bed available for cargo, so I went with a Titan 55 gallon diesel tank to replace the stock 32 gallon on my 2020 RAM 3500 dually. That give me a comfortable 450+ mile range towing my 5th wheel toyhauler.

That is a point. In my case, with aux tank plus 5th wheel hitch (that is VERY HEAVY), plus short bed, makes my truck pretty much a camper hauler only. I'll have to rent a utility trailer if I need to bring home a sheet of plywood!