I have a 2021 Ram dually DSl mega cab just bought our first fifth wheel Jayco 347 BHOK which is 42 ft long last TT was 36 ft long so length behind truck not much different but would like to add a seperate fuel tank to the bed of truck looks like smallest i can find right now would be about 38 gallons which would be ok. My thoughts are putting in back of truck next to front of bed would like to run a line to gravity feed into existing tank with a valve that i could open when tank gets towards empty. With that setup I could run all day without trying to find a gas station with easy in out for this long of a rig. Hope would be to find stop for the night set up unhook and go get fuel without rig behind. Anybody done this or having any idea's on my thoughts. The big 50 gal tank is not an option for the megacab shortbeds.

No issue with what you’re proposing. It’s very common. The most convenient way is to make it full time gravity feed with a check valve. Just buy a gravity kit from one of the popular mfgs for ease of install.

Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops. If you want more capacity get a TITAN 50 gallon replacement tank. Then you still have room for a toolbox. What is DSI ?

OK but once I get to my campsite and setup, I want to stay in my campsite.

Cummins12V98 wrote:Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops. If you want more capacity get a TITAN 50 gallon replacement tank. Then you still have room for a toolbox. What is DSI ?DSI = Diesel

Getting an auxiliary fuel tank is one of the best things you can do. It becomes the scenario where you stop when you want to, not when the truck demands it. If you never travel off the interstates, it's less of an issue, but get off on the two lanes and those big ol' truck stops are fewer and farther between. Personally I'd rather stop at a city park, rest stop, or almost anyplace rather than spend time at a truck stop. And my long day of travel is about 250-300 miles. :) I can usually travel two days before I have to refuel.I believe the newer versions of the injector pumps are very intolerant of any water or rust, so you may be better off using an aluminum tank. I have a 35 gallon steel tank, and it is the perfect size for me, but I also have an old diesel engine that isn't as fussy as the new ones.

Additional fuel tank | Good Sam Community

Grit_dog
Navigator
Jan 02, 2022
No issue with what you’re proposing. It’s very common. The most convenient way is to make it full time gravity feed with a check valve.
Just buy a gravity kit from one of the popular mfgs for ease of install.
Cummins12V98
Explorer III
Jan 02, 2022
Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops.

If you want more capacity get a TITAN 50 gallon replacement tank. Then you still have room for a toolbox.

What is DSI ?
Lwiddis
Explorer II
Jan 02, 2022
OK but once I get to my campsite and setup, I want to stay in my campsite.
FishOnOne
Nomad
Jan 02, 2022
Cummins12V98 wrote:
Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops.

If you want more capacity get a TITAN 50 gallon replacement tank. Then you still have room for a toolbox.

What is DSI ?

DSI = Diesel
fj12ryder
Explorer III
Jan 02, 2022
Getting an auxiliary fuel tank is one of the best things you can do. It becomes the scenario where you stop when you want to, not when the truck demands it. If you never travel off the interstates, it's less of an issue, but get off on the two lanes and those big ol' truck stops are fewer and farther between.

Personally I'd rather stop at a city park, rest stop, or almost anyplace rather than spend time at a truck stop. And my long day of travel is about 250-300 miles. :) I can usually travel two days before I have to refuel.

I believe the newer versions of the injector pumps are very intolerant of any water or rust, so you may be better off using an aluminum tank. I have a 35 gallon steel tank, and it is the perfect size for me, but I also have an old diesel engine that isn't as fussy as the new ones.
larry_barnhart
Explorer
Jan 02, 2022
Our 55 gal inbed fuel tank has worked great for us as above feels. best thing is we had it built when our 05 truck was new. chevman
Bionic_Man
Explorer
Jan 03, 2022
I put a 60 gallon RDS auxiliary tank into my truck when I bought it new 10 years ago. For me, it has been one of the best upgrades I could do to a truck. When I finally upgrade from this truck, I will 100% do it again.
valhalla360
Navigator
Jan 03, 2022
Cummins12V98 wrote:
Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops.

If you are doing back to back to back travel days...sure.

If you stop for 2-3 days between runs, not being limited to truck stops is nice.
Cummins12V98
Explorer III
Jan 03, 2022
FishOnOne wrote:
Cummins12V98 wrote:
Simply don’t get this get to camp after a long day and go get fuel. Simply hit the truck stops.

If you want more capacity get a TITAN 50 gallon replacement tank. Then you still have room for a toolbox.

What is DSI ?

DSI = Diesel

DS “L” is diesel but never heard of anyone using an upper case “I”.
fishhogg
Explorer
Jan 03, 2022
Ck out “Transfer Flow” fuel tanks. I bought their 50gal./ 10 cu.ft tool box combo. Great fit and finish and their made in the U.S.A. ??