Aux Tank install on 2020

[bcbender]

Hello all. I was going back and forth on aux tank vs. Titan 55gal . Mopar 50gal but since I assume the Mopar 50 gal would be cost prohibitive, but then I landed on a great deal on this RDS 60gal tank.

I have decided I am going to make it so I can take in/out so when I want my 8' bed I can which will not coincide with me needing 90 gal of fuel. That being said I see no kits to install on the 19'+ MY models. I was thinking to remove the filler tube and weld a bung in it to connect the 3/8 line from the tank but cannot get the FSM to know how to properly remove it, I don't want to damage the filler tube, or anything since the truck is NEW and not ready to break things in the process. Do I need to also connect the vent line to the tank vent? I was thinking about mounting a small pump, Normally closed check valve, and really good! water separating filter down under the bed so that I can pump it though a filter into the tank when I hit 1/4 empty on main tank. I think I saw some 100% water absorbing filters somewhere here on the TDR, not sure how big a pump (GPH) I need to push fuel through them. Thought was topside I could simply use some turnbuckles to tie it down and a hydraulic quick connect for the fuel line.... Thoughts ? Ideas? Tech Authority is "out of stock" on FSMs so I may have to wait to pull the filler neck.

 

[bcbender]

Oh also... I have heard that Northern Tool sells a Kit for the 13'-18'MY gravity, and the guy I got this from said they have a check valve to keep the tank from overfilling, I think I read that the 19' up will set a CEL if the tank is overfilled, is that true? Also not too sure about getting water from Aux tank to main tank via gravity? Will the capless system work in this case?

 

[Ltngdrvr]

The filler neck on the newer trucks has not changed AFAIK, so install should be identical to my install.
There is zero need to fool with a pump and extra filters, gravity feed works great and your truck already has water separating filters that all the fuel will pass through, so why would you need or want to complicate that???
RDS makes a gravity fill kit, which I'm sure is the one that northern tools sells. It comes with a "T" that you splice into the filler neck tube, and the check valve screws into that, then the gravity feed hose connects to that. You then just let the gravity feed constantly transfer fuel from the aux tank to your truck main tank. The check valve will not let the tank overfill so long as you install it in its proper orientation, which should be with the check valve upright, above the filler neck tube.
I have been running my 60 gallon RDS tank for 6 years trouble free, and it has paid for itself in fuel cost savings and time savings many, many times over.
As to any quick disconnects for the fuel line, I guess you can do that, the gravity feed kit comes with a shutoff valve so you can just use that. As to any sort of quick release tie downs, you could maybe use ratchet straps and tie it to the tie down loops at the bed corners.
If you want to, you can go to cumminsforum and search under my user name and I made a install thread when I put my RDS tank in my truck.

Also, don't know anything about any FSM or any check lights for overfilling.
And, removing the filler neck is a bit of a PITA, it is rivetted to the opening up top, bottom just has a hose clamp, along with the vent line, and remove the fender liner for easier access.

 

[AH64ID]

I believe the overfilling CEL was for the 19+ DEF tanks, not the fuel tanks.

 

[Wiredawg]

Hello all. I was going back and forth on aux tank vs. Titan 55gal . Mopar 50gal but since I assume the Mopar 50 gal would be cost prohibitive, but then I landed on a great deal on this RDS 60gal tank.
View attachment 127148
I have decided I am going to make it so I can take in/out so when I want my 8' bed I can which will not coincide with me needing 90 gal of fuel. That being said I see no kits to install on the 19'+ MY models. I was thinking to remove the filler tube and weld a bung in it to connect the 3/8 line from the tank but cannot get the FSM to know how to properly remove it, I don't want to damage the filler tube, or anything since the truck is NEW and not ready to break things in the process. Do I need to also connect the vent line to the tank vent? I was thinking about mounting a small pump, Normally closed check valve, and really good! water separating filter down under the bed so that I can pump it though a filter into the tank when I hit 1/4 empty on main tank. I think I saw some 100% water absorbing filters somewhere here on the TDR, not sure how big a pump (GPH) I need to push fuel through them. Thought was topside I could simply use some turnbuckles to tie it down and a hydraulic quick connect for the fuel line.... Thoughts ? Ideas? Tech Authority is "out of stock" on FSMs so I may have to wait to pull the filler neck.

I use gravity feed on my 2017 Ram 5500 with the RDS 60 gallon toolbox/fuel tank combo with 1/2 valve, fittings, and fuel line that works great. Never had any fuel spillage from my primary tank when opening valve and effectively acting like one tank. I installed an overflow bottle on my aux tank as topping off the aux more than 95% fuel can expand causing some spillage. No problem ever if you fill to 55 gallons.

FYI, on my former 09 Ram 4500, I had the same setup, except I used a FASS to transfer fuel and used 1/2" hardware/ hoses. I typically transferred fuel when I was a little below 1/4 tank on my primary. Well, once I started the transfer, got caught in heavy traffic and construction zone. forgot I was transferring fuel, and blew out the turnover safety ball valve on primary tank. forcing at least 25 gallons of fuel giving bottom rear of truck and fiver a diesel bath. I recommend if using a transfer pump, installing a pressure cutoff switch in line with the pump operate circuit.

Hope this helps some.

Cheers, Ron

 

[JR]

I would be leary of true quick connect fittings. The potential for leaks would have me uneasy.
Something like a JIC fitting would be very secure and easily removable. If you are looking for fuel lines and fittings this is a good place to get them from. Keep in mind the prices are by the foot.

http://www.vulcanperformance.com/mobile/Category.aspx?id=181

 

[bcbender]

Primary reason for the pump would be to filter fuel "one more time" before dropping it into the main tank, but that sounds like maybe its a moot point with the 20' filter setup. When you dit the 1/2 line, did you make your own adaptor or use off the shelf parts?

 

[AH64ID]

Primary reason for the pump would be to filter fuel "one more time" before dropping it into the main tank, but that sounds like maybe its a moot point with the 20' filter setup. When you dit the 1/2 line, did you make your own adaptor or use off the shelf parts?

It's been a moot point since '13 when Ram went to dual fuel filters with the NanoNet secondary fuel filter.

On a diesel very little fuel is burned with only being filtered one time, so it's constantly being polished.

 

[Ltngdrvr]

Primary reason for the pump would be to filter fuel "one more time" before dropping it into the main tank, but that sounds like maybe its a moot point with the 20' filter setup. When you dit the 1/2 line, did you make your own adaptor or use off the shelf parts?

You're just making extra work for yourself with no upside to it.
The gravity feed install kit that RDS makes and northern tool sells, is all you need to make a perfectly good connection to the main tank. Run it open all the time and never look back.
Trying to change to a 1/2" line will make using the check valve on the filler neck impossible, it is meant for a 5/16-3/8 hose.
Thousands upon thousands of truck owners have used the gravity feed system without any added filters for many years with no issues.
But, hey, it's your truck do as you please.
Any other money you want to waste, I'm open to donations to my retirement fund...

 

[R.Taylor]

Correct.... DEF overfill will cause CEL. Fuel overfill will get you about 15 more miles

 

[bcbender]

thank you all for the information, I am new to these trucks and their quirks, as I had a 04 before an filtration was paramount, I wanted to make sure and CYA.

 

[bcbender]

you can go to cumminsforum and search under my user name and I made a install thread when I put my RDS tank in my truck.

Thank you, I will look for the install, I saw that you said its riveted, that is what I was concerned about how hard it was to pull it from the truck,,. I'll look through your write up first before asking more questions... Thank you Ltngdrvr

 

[Ltngdrvr]

Correct.... DEF overfill will cause CEL. Fuel overfill will get you about 15 more miles

Fuel overfill on the main tank will get a messy fuel drip off the bottom of the bedside under the fuel filler...

 

[Wiredawg]

off the shelf fittings, bought them at Northern Tools.... bought pipe at HD, threaded it to accept half inch barb fitting.

Nothing wrong with the RDS kit, except fittings and fuel line either 1/4 inch or 3/8 inch. I just wanted faster flow. Never leaked a drop from primary tank on my 2017, bit it is a C&C.

Cheers, Ron

 

[Ltngdrvr]

off the shelf fittings, bought them at Northern Tools.... bought pipe at HD, threaded it to accept half inch barb fitting.

Nothing wrong with the RDS kit, except fittings and fuel line either 1/4 inch or 3/8 inch. I just wanted faster flow. Never leaked a drop from primary tank on my 2017, bit it is a C&C.

Cheers, Ron

But, all of that is unnecessary, the truck doesn't use fuel faster than the smaller hose can refill the tank. And, you don't have to fool with shutting the valve off to stop the fuel from overfilling the main tank.

 

[HarryOlson]

I’m late to this but here’s a photo of the installation of my 2019 with a 90 gallon aux bed tank. Very simple and it has yet to leak. I fill the main tank first and the aux tank second. The aux tank has a shutoff but is always left open.

 

[Wiredawg]

But, all of that is unnecessary, the truck doesn't use fuel faster than the smaller hose can refill the tank. And, you don't have to fool with shutting the valve off to stop the fuel from overfilling the main tank.

OK, I give Uncle.

 

[bcbender]

Mr. Olson, did you pull the filler neck to make the connection? Do you have the "check valve" that prevents overfilling? I was thinking about doing it that way as I did not want to cut the filler neck off, I figured weld in a bung, two fittings and a $25 normally closed solenoid valve and Id be in business for much less than the various kits out there and bonus, I could dictate when / if I want to transfer fuel. Second and most popular option is how Ltngdrvr did it and just buy the NT kit but still have to pull the filler tube to cut it. I assume neither of these will void the warranty unless its regarding the filler tube . I assume there are no real negative effects to driving the truck with 60 extra gallons of fuel sitting above the full level... the DTE gauge will be a total waste of time!, I may just delete it and put the trans temp gauge there... I really like the scrolling temp gauge for the coolant temp

 

[HarryOlson]

Mr. Olson, did you pull the filler neck to make the connection? Do you have the "check valve" that prevents overfilling? I was thinking about doing it that way as I did not want to cut the filler neck off, I figured weld in a bung, two fittings and a $25 normally closed solenoid valve and Id be in business for much less than the various kits out there and bonus, I could dictate when / if I want to transfer fuel. Second and most popular option is how Ltngdrvr did it and just buy the NT kit but still have to pull the filler tube to cut it. I assume neither of these will void the warranty unless its regarding the filler tube . I assume there are no real negative effects to driving the truck with 60 extra gallons of fuel sitting above the full level... the DTE gauge will be a total waste of time!, I may just delete it and put the trans temp gauge there... I really like the scrolling temp gauge for the coolant temp

I had my tank made at KSH Fuel in Lake Havasu City, AZ and they installed it. My truck filler neck has a check valve built in and it works. The only change you might notice with these trucks when you add 120 gallons of fuel to an empty truck is that it rides a little better. For additional information, give KSH a call at 928-680-6610. I have no financial interest in the company, they were just good to deal with.

 

[bcbender]

So I read the tread on Cummins forum, and I think I am going to give Ltngdrvr's install a go. I have everything from the previous owner's install except the pipe with the check valve in it. Does anyone know if /where you could purchase just the brass valve? I would prefer to pull the filler tube and simply weld a bung in it, then re-install with out the extra pipes, etc.. and since I already have the shutoff valve on the tank and the vent / fuel lines, the only thing I need from the kit is the check valve. I am having a hard time with spending almost a $100 on the RDS kit for that valve. Is it just a simple differential pressure valve?