First of all, some states have laws concerning an auxiliary fuel tank, mostly the laws are more for gas & not diesel.
I can't directly connect
my 2nd gas
tank into my fuel system, because of smog laws in California. I believe if it was diesel then i could.
My lighted power switch
is mounted on my dash, i have 2 of them, one for fuel & the other for my above cab caution lights
My tank is a combo tank, 30 gallon capacity with a tool box above that is large enough for something like hard hats & tools
The auxiliary tank that i bought, sits in front of bed, holds 30 gallons, & has its own pump, i have to open the top lid & put the nozzle into my Rams regular fuel access, ( like you would at the gas station), then i have to turn the power on at the dash, then turn on another switch that is at the pump & it pumps gas faster then the gas station nozzles.
the front box in the Rams bed is the auxiliary tank
The company that makes the tank that i used makes several styles of tanks with several different capacities.
They make a add on part that will automatically pump fuel from the 2nd tank to the first, when the primary tank gets down to a certain point, like 1/3 tank, as long as you have power to the pump. Another add on that they sell measures the amount of fuel that was pumped from the second tank, so you know how much fuel is still in the 2nd tank
MY friend set up his own system & it works well, BUT, on more than 1 occasion, he has forgot that his pump was pumping & he pumped fuel all over the highway that he was driving on.
The name of the company that makes this tank is Transfer Flow
, the tank sits on skids, so that you can flush any trash that may build up in front or under the tank.
You can get the tanks through several places across the USA, including Northern Tool stores, many larger businesses have at least one tank in stock, they place that i bought mine from had 4 of them in stock
The website is