Auxiliary Fuel Tank/Tool Box Thoughts/Advise

[FireRob]

Hello once again, been awhile since last post, probably a good thing meaning I haven't had any problems.

The short and sweet:

Looking for a combo Auxiliary Fuel Tank/Tool Chest. If you don't want to read any further by all means go ahead and tell me what you know, Ill read it. If you want more details read on.

Long Story long:

Looking to get an auxiliary fuel tank to add to my truck. I did some minor research several weeks back but not much since. It was enough to raise some questions. Id like to get a combo unit that has the fuel tank and tool box because I have always had a tool box on my trucks and don't want to be with out one. I have found three options,

Option 1 is a siphon/gravity fed type that as fuel is used in the OEM tank it is automatically replaced with fuel from the aux tank above and basically your fuel gage never shows a drop in fuel until you have used all fuel in the aux tank. The Option 2 I have seen is the pump fed tanks that once the OEM tank drops below a 1/4 tank a pump in the aux tank kicks in and refills the OEM tank. First option being much cheaper than the second.

My concerns about option 1 came from reading the sales info from a manufacture of a option 2 type tank. They said with their system you wont get the check engine light that you would from using a option 1 style (syphon/gravity). Basically they stated that with a option 1 the fuel gage always reads full and the truck assumes something is wrong with the gage and then the check engine light comes on. Is this true? Anyone have first hand experience? According to reviews it was Chevy and Ford owners who were having this problem. Maybe Dodge/Ram owners are as well and just didn't say anything about it. (I have a Ram incase you didn't know)

Option 3 Is replacing the OEM fuel tank for an aftermarket one that is much bigger. Don't really want to do this one....

Thanks in advance for any advise and words of wisdom or caution you might have.

[tinner12002]

I am also thinking about using the RDS tank and toolbox combo with gravity feed but I plan on using a manual shutoff valve and a 12volt normally closed solenoid shut off valve also so I can drain extra tank into truck tank by flipping a switch and without stopping. Can't imagine how that could cause an engine light issue, plan on gauge showing about 1/4 tank before opening solenoid valve to fill tank back up.

[Cummins12V98]

jus2shy wrote:

Cummins12V98 wrote:
^^^^^ Not true, RAM had capless fill on the 15's and I do believe starting with the 13's.

I own a 13, it is capless. And it has both fillers behind the door (DEF and Diesel).

Thanks!

[Rygar]

I went the option you didn't want to do. I had a 50gal aftermarket tank installed. I'm happy with carrying that much fuel.

[jus2shy]

Cummins12V98 wrote:
^^^^^ Not true, RAM had capless fill on the 15's and I do believe starting with the 13's.

I own a 13, it is capless. And it has both fillers behind the door (DEF and Diesel).

[retispcsi]

My 2014 has the dual tube filler neck started in 2013 when they went to DEF. I have a RDS 60 gal. I used it in my 2012 and now my 2014. No issues. I found out that the hose supplied with the adaptor kit on the fill tube needs to be longer so I bought some from a local NAPA store. I also used two clamps solved any leak issue. Also make sure you clamps are tight and that you have secured the brass connector to the filler kit. As far as the check engine light and gas gauge issue never had that problem.

[Bionic_Man]

MtnMike wrote:
RDS 60 gallon aux gravity-fed tank/toolbox combo installed in the bed of my 2017 Dodge Ram 3500 DRW. A drip-drip-drip leak became a torrential rush after leaving the manual valve open after a fill-up. Stopping at a restaurant and there was a puddle of diesel fuel running down the parking lot after dinner. Turning the valve off stopped the flood of expensive fuel, but discovered the capless filler tubes of the 2016 and 2017 Dodge Ram's and the inner flapper valve is unable to stop the overflow of fuel through the open filler neck. Multiple check valve companies did not know if their valves would resolve the overflow issue either. Frustrated, I went old-school and looked for a solution that would cap off the stock filler neck. In 2016, Dodge introduced dual filler tubes behind the filler door; one to fill the diesel exhaust fluid (DEF) which had a filler cap and an open filler cap for diesel fuel and a flapper overflow valve in the filler neck. With the gravity-fed RDS auxiliary fuel tank/toolbox combo that RDS claims fits 2006 and newer Dodge Rams, those from 2016 and 2017 with open filler necks will have overflow problems that the flipper valve will not stop. I replaced the open-neck filler tube with a modified Ford filler neck and a standard filler cap. Old-school. No leaks. No problems. I was also concerned about the safety in a roll-over accident. If the regular overflow valve would not stop the fuel in an upright position, what would happen in a roll-over?

Did you double check to see if the cap on your aux tank was tight? My RDS cap went bad, and caused a leak as well. Replaced that cap, and all is good again.

[Cummins12V98]

^^^^^ Not true, RAM had capless fill on the 15's and I do believe starting with the 13's.

[MtnMike]

RDS 60 gallon aux gravity-fed tank/toolbox combo installed in the bed of my 2017 Dodge Ram 3500 DRW. A drip-drip-drip leak became a torrential rush after leaving the manual valve open after a fill-up. Stopping at a restaurant and there was a puddle of diesel fuel running down the parking lot after dinner. Turning the valve off stopped the flood of expensive fuel, but discovered the capless filler tubes of the 2016 and 2017 Dodge Ram's and the inner flapper valve is unable to stop the overflow of fuel through the open filler neck. Multiple check valve companies did not know if their valves would resolve the overflow issue either. Frustrated, I went old-school and looked for a solution that would cap off the stock filler neck. In 2016, Dodge introduced dual filler tubes behind the filler door; one to fill the diesel exhaust fluid (DEF) which had a filler cap and an open filler cap for diesel fuel and a flapper overflow valve in the filler neck. With the gravity-fed RDS auxiliary fuel tank/toolbox combo that RDS claims fits 2006 and newer Dodge Rams, those from 2016 and 2017 with open filler necks will have overflow problems that the flipper valve will not stop. I replaced the open-neck filler tube with a modified Ford filler neck and a standard filler cap. Old-school. No leaks. No problems. I was also concerned about the safety in a roll-over accident. If the regular overflow valve would not stop the fuel in an upright position, what would happen in a roll-over?

[Bionic_Man]

FireRob wrote:
Many thanks for all the replies and information. It is in fact the RDS brand from Northern Tool that I was/am leaning towards.

Any advise, tips, words of caution/wisdom or photos of the install process?

I did your "option 1" with a 60 gallon RDS from Northern Tool. 50,000 miles later, it works great, and no check engine lights.

It sure is nice to stop when and where you want to stop, instead of stopping where you need to stop. One of the better upgrades I have done to the truck.

[fly-boy]

I have a 65 gallon under bed tank- more expensive but you still have the use of your entire bed. It gives me nearly a 1k mile range and I have to get out and stretch etc. long before I get anywhere near that far... My check fuel light goes on when I have 10 gallons left in the tank so plenty of range to find a fuel station.

I considered the combo tool/fuel box on this truck and have had it on others but wouldn't go back.

[larry_barnhart]

We really like our 55gal in bed tank. We have a towing only. Chevman

[Cummins12V98]

So far I have not wanted a in bed fuel tank. I pack a 5 in my bed height 30" front to back HighwayProductstool box.

Traveling the Western States I found fuel when I needed it.

[transamz9]

FireRob wrote:
Hello once again, been awhile since last post, probably a good thing meaning I haven't had any problems.

The short and sweet:

Looking for a combo Auxiliary Fuel Tank/Tool Chest. If you don't want to read any further by all means go ahead and tell me what you know, Ill read it. If you want more details read on.

Long Story long:

Looking to get an auxiliary fuel tank to add to my truck. I did some minor research several weeks back but not much since. It was enough to raise some questions. Id like to get a combo unit that has the fuel tank and tool box because I have always had a tool box on my trucks and don't want to be with out one. I have found three options,

Option 1 is a siphon/gravity fed type that as fuel is used in the OEM tank it is automatically replaced with fuel from the aux tank above and basically your fuel gage never shows a drop in fuel until you have used all fuel in the aux tank. The Option 2 I have seen is the pump fed tanks that once the OEM tank drops below a 1/4 tank a pump in the aux tank kicks in and refills the OEM tank. First option being much cheaper than the second.

My concerns about option 1 came from reading the sales info from a manufacture of a option 2 type tank. They said with their system you wont get the check engine light that you would from using a option 1 style (syphon/gravity). Basically they stated that with a option 1 the fuel gage always reads full and the truck assumes something is wrong with the gage and then the check engine light comes on. Is this true? Anyone have first hand experience? According to reviews it was Chevy and Ford owners who were having this problem. Maybe Dodge/Ram owners are as well and just didn't say anything about it. (I have a Ram incase you didn't know)

Option 3 Is replacing the OEM fuel tank for an aftermarket one that is much bigger. Don't really want to do this one....

Thanks in advance for any advise and words of wisdom or caution you might have.

I have had a gravity feed in a 2013 Ram Cummins and now in my 2016. No problems what's so ever.I even go as far as when I don't need both tanks (in between long trips) I just fill up the tank in the back of the truck and let it gravity feed into the main tank. I hate sticking a nozzle in the capless filler neck on the truck. It feels like it's going to rip the flaps right out of it every time I pull it out. One of these days I'm going to be seen with a fuel nozzle sticking out of the side of my truck going down the road. LOL

[Doss]

Interesting topic. I don't make as many long trips as you guys do so I would be interested in something easily removable.
I am thinking of getting a tank with a transfer pump. When I get home, I can use up the fuel, unbolt it and set it out till next time.
Anyone used this type of setup?

Thanks