I'm considering deleting my original fuel tank and just running off of my 100 gallon auxiliary. Will it cause a problem for my fuel return to be running uphill to the tank? I'm concerned about back pressure to the injectors.
Howdy! I think the return would be ok. Though, if your truck is new enough to have an electric lift pump in the tank to supply the cp3 you'd need to move that to the aux somehow. Thanks!
I would say if definitely need a vent of some sort. The screw on fill cap has a very good seal so without any vent it will probably only drain 5 or so gallons out before it creates a vacuum in the tank and stops flowing.
I just installed a 60 gallon rds tank. OEM tank is not full. Put 15 gallons in new aux tank. Fuel will not flow unless I hold filler door open. You mention similar issue. Did it work properly when you filled oem tank first? Or is it a venting problem?
Yep. It won't fill the tank but it will maintain whatever level is in the primary to start with. Fill the primary, fill the aux then it should work fine. Mine"s been absolutely flawless. Thanks!
Are you going to add a fuel filter to the aux tank? The only problem I had over the non use season was the check ball got stuck and would not fuel drain from the aux tank. So I use it once a month in the off season.
I haven't to this point and it's been ok. Looking into the tank when I fill it and it's still clean. I'd be a little concerned that it might not gravity feed through a filter very well. So far so good though. Thanks!
Howdy! It's been great. No issues at all. No leaks and when driving you don't even know it's there. Towing my camper with the sxs on the truck bed cover I get around 8-9 mpg at about 21k gvcw. Having 85 usable gallons takes a lot of anxiety about fueling on the road out of the picture. Thanks!
Works perfectly. Best upgrade to the truck so far. Plus I can drive a few miles to get fuel at $1.70/gallon near home instead of $2.30 on the road saving $36/fill-up.
Thanks! If I'm parking it for a while between the I'll close it but if I'm using it I leave it open. As long as the check valve in the fuel neck is good it won't leak. Just fill up the main tank first then fill the aux. If will keep the tank at the level it was when it started. It won't fill an empty tank.
This setup won't fill the tank the way the new systems are designed with the tank sealed. It will keep the main tank at whatever level it starts at until the aux tank is empty then the main tank level will drop as normal. So I always fill the main tank first, then fill the aux. Thanks!
Excellent video! My RDS 50gal combo arrives In a couple of days. About a month ago I upgraded the 32gal Ram factory tank with a 55gal Titan tank and was still not enough so now I will be good to GO! Pulling a 42' 19k plus 5th wheel this will be an awesome improvement! I hear of folks having the tank vent spit fuel when the tanks heat up due to expansion. I think maybe the check valve in the filler neck have been defective in some trucks. Sea ya down the Road! Thanks
I got a 2019 F250 Limited Long bed with the Diamond back HD cover just like yours, thanks for your awesome video, now I need to get me a tank lol not the factory 48 gallon is not sufficient.
Thanks! I wasn't sure I'd like the extra fuel when I did it. Now I don't know how I ever towed without it. I need to do a full video on the diamondback. It's phenomenal.
I previously had a 2013 Ram 2500 that I installed an auxiliary tank on and I was able to fill the primary tank through the auxiliary tank. I’m getting ready to install a tank on my 2019 Ram 2500. I’m hoping I’ll be able to fill my primary tank the same way, but based on your observation, it doesn’t seem likely.
Great video just a heads up.. down the road..Add an electric Solaniod on/off for $20 and get a 9 psi fuel pump for $20 . Buy a filter water seperator for $20. JMO
I'm trying to find info on doing this right now, which is how I found this video. Do you have instructions or videos on how to do that? I'm wanting to change my gravity feed to electric pump.
Paul, I keep hearing that gravity fed auxiliary fuel tanks are illegal per FMCSA. I see where it says that but it also states that it cannot feed the carburetor or injectors from siphon or gravity feed. What’s your take?
Interesting comment. I read the CFR 393.65 and specifically the 393.65-d "Gravity or syphon feed prohibited. A fuel system must not supply fuel by gravity or syphon feed directly to the carburetor or injector." Interpreting this as it is written, an aux tank, mounted securely in the bed of a pickup with a gravity feed into the primary tank, is acceptable. The gravity feed portion of the tank only refills the primary tank which uses a pump or combination of pumps to get the fuel to the carb or injectors. The fuel is not gravity feeding directly into the carb or injectors. I think this would be exceedingly difficult to accomplish with modern diesels that use lift pumps and then high pressure pumps to inject the fuel. Going to the absurd, if you mounted a diesel tank on the roof of a 1st gen dodge with a cummins, you'd still be OK within this as you would be gravity feeding the P-pump and not directly the carb or injectors. Reading the rest of this piece of the CFR, I am comfortable that my aux tank meets all of the requirements in this section. Excellent question. Thanks for asking!
Great video sir. I am putting a 90 gal RDS tank in my 2020 ram 3500. I have a question/idea. On the aux tank vent could we T it to the main tank vent to slow down the amount of condensation in the tank? I have a 1994 f250 with a 12v Cummins and a 60 gal RDS tank and seems like I get a lot of water in my primary/water filter on my FASS pump. I have a old school fuel filter on the vent line. But I do live in E TX so humidity is high year round! Thank you
Only thing I could think about hooking the vent to the main tank is it might balance the pressure in the auxiliary tank and not drain properly. On my Ram there are 2 water separators so I don't worry about condensation. Thanks!
I'm considering deleting my original fuel tank and just running off of my 100 gallon auxiliary. Will it cause a problem for my fuel return to be running uphill to the tank? I'm concerned about back pressure to the injectors.
Howdy! I think the return would be ok. Though, if your truck is new enough to have an electric lift pump in the tank to supply the cp3 you'd need to move that to the aux somehow. Thanks!
@@aaronsrose no worries there lol. It all mechanical. 12 valve cummins
Also thanks for making the video helps other goof balls complete there projects ! Happy new year !
My only Q ? What diid you use at the end of your vent tube ??
Actually nothing. Just stuck it into the stake pocket. I should probably check to see if a mud dauber has plugged it up yet. Thanks!
Thank you again I’m in the process of mine now ! Do I need to vent or just don’t fill it all the way on the fence hahaha happy new year !🎊
I would say if definitely need a vent of some sort. The screw on fill cap has a very good seal so without any vent it will probably only drain 5 or so gallons out before it creates a vacuum in the tank and stops flowing.
They would possibly break that somehow and siphon your fuel
Anything is possible but unlikely I think. So far no issues.
I just installed a 60 gallon rds tank. OEM tank is not full. Put 15 gallons in new aux tank. Fuel will not flow unless I hold filler door open. You mention similar issue. Did it work properly when you filled oem tank first? Or is it a venting problem?
Yep. It won't fill the tank but it will maintain whatever level is in the primary to start with. Fill the primary, fill the aux then it should work fine. Mine"s been absolutely flawless. Thanks!
Are you going to add a fuel filter to the aux tank? The only problem I had over the non use season was the check ball got stuck and would not fuel drain from the aux tank. So I use it once a month in the off season.
I haven't to this point and it's been ok. Looking into the tank when I fill it and it's still clean. I'd be a little concerned that it might not gravity feed through a filter very well. So far so good though. Thanks!
Great video, thank you!
Any follow up thoughts. I just ordered one for my new 2021 RAM. Im Super excited. Any advice you you might have would be appreciated.
Howdy! It's been great. No issues at all. No leaks and when driving you don't even know it's there. Towing my camper with the sxs on the truck bed cover I get around 8-9 mpg at about 21k gvcw. Having 85 usable gallons takes a lot of anxiety about fueling on the road out of the picture. Thanks!
I bet. Thank you for the reply.
Any updates ?
Works perfectly. Best upgrade to the truck so far. Plus I can drive a few miles to get fuel at $1.70/gallon near home instead of $2.30 on the road saving $36/fill-up.
awesome!! I’m doing it to my truck today thanks a lot for your video. Do you keep the valve open or you close it after you re full ?
Thanks! If I'm parking it for a while between the I'll close it but if I'm using it I leave it open. As long as the check valve in the fuel neck is good it won't leak. Just fill up the main tank first then fill the aux. If will keep the tank at the level it was when it started. It won't fill an empty tank.
Got it 👌👌👌
Are u worried about water build up an do u think the fuel filters need to changed more frequently
How fast does it fill up your tank once you open the valve?
This setup won't fill the tank the way the new systems are designed with the tank sealed. It will keep the main tank at whatever level it starts at until the aux tank is empty then the main tank level will drop as normal. So I always fill the main tank first, then fill the aux. Thanks!
@@aaronsrose interesting. Where can I find the new system? Thanks for sharing
Excellent video! My RDS 50gal combo arrives In a couple of days. About a month ago I upgraded the 32gal Ram factory tank with a 55gal Titan tank and was still not enough so now I will be good to GO! Pulling a 42' 19k plus 5th wheel this will be an awesome improvement!
I hear of folks having the tank vent spit fuel when the tanks heat up due to expansion. I think maybe the check valve in the filler neck have been defective in some trucks. Sea ya down the Road!
Thanks
I bought a rubber grommet but thinking maybe a section of wire loom and protect the entire hose run might be a better solution.
That wouldn't hurt.
I got a 2019 F250 Limited Long bed with the Diamond back HD cover just like yours, thanks for your awesome video, now I need to get me a tank lol not the factory 48 gallon is not sufficient.
Thanks! I wasn't sure I'd like the extra fuel when I did it. Now I don't know how I ever towed without it. I need to do a full video on the diamondback. It's phenomenal.
I previously had a 2013 Ram 2500 that I installed an auxiliary tank on and I was able to fill the primary tank through the auxiliary tank. I’m getting ready to install a tank on my 2019 Ram 2500. I’m hoping I’ll be able to fill my primary tank the same way, but based on your observation, it doesn’t seem likely.
It's not bad. Unless I'm parking it for a while I just leave the ball valve open and it's keeps the main full. No issues so far.
Great video just a heads up.. down the road..Add an electric Solaniod on/off for $20 and get a 9 psi fuel pump for $20 . Buy a filter water seperator for $20. JMO
I'm trying to find info on doing this right now, which is how I found this video. Do you have instructions or videos on how to do that? I'm wanting to change my gravity feed to electric pump.
Interesting mod and relatively easy too! Thanks Aaron.
Paul, I keep hearing that gravity fed auxiliary fuel tanks are illegal per FMCSA. I see where it says that but it also states that it cannot feed the carburetor or injectors from siphon or gravity feed. What’s your take?
Interesting comment. I read the CFR 393.65 and specifically the 393.65-d "Gravity or syphon feed prohibited. A fuel system must not supply fuel by gravity or syphon feed directly to the carburetor or injector." Interpreting this as it is written, an aux tank, mounted securely in the bed of a pickup with a gravity feed into the primary tank, is acceptable. The gravity feed portion of the tank only refills the primary tank which uses a pump or combination of pumps to get the fuel to the carb or injectors. The fuel is not gravity feeding directly into the carb or injectors. I think this would be exceedingly difficult to accomplish with modern diesels that use lift pumps and then high pressure pumps to inject the fuel. Going to the absurd, if you mounted a diesel tank on the roof of a 1st gen dodge with a cummins, you'd still be OK within this as you would be gravity feeding the P-pump and not directly the carb or injectors. Reading the rest of this piece of the CFR, I am comfortable that my aux tank meets all of the requirements in this section. Excellent question. Thanks for asking!
@@aaronsrose Great reply
Great video on your aux tank install! One ding, put a grommet in that bed. Think long term insurance.
I do need to do that. Lol. Thanks!
Great video sir. I am putting a 90 gal RDS tank in my 2020 ram 3500. I have a question/idea. On the aux tank vent could we T it to the main tank vent to slow down the amount of condensation in the tank? I have a 1994 f250 with a 12v Cummins and a 60 gal RDS tank and seems like I get a lot of water in my primary/water filter on my FASS pump. I have a old school fuel filter on the vent line. But I do live in E TX so humidity is high year round! Thank you
Only thing I could think about hooking the vent to the main tank is it might balance the pressure in the auxiliary tank and not drain properly. On my Ram there are 2 water separators so I don't worry about condensation. Thanks!