Under trailer mounted aux fuel tank?

What many are missing, and what @Xray4 is trying to say is that the step deck style trailer is different than your standard goose neck. With a full 102" wide deck riding right above the pin, not on top of a gooseneck. that means with a 60" cab to axle length of a long bed pickup with bed removed, he will only have 12" or so between the trailer and the cab at a 90 degree turn.

 

BTW.. an 9" tall, 48" x 96" tank is right about 180 gallons. Would probably fit on the flatbed in front of the trailer and the trailer would clear it at all turn angles and quite a bit of side tilt. There's a bunch of places that would weld you up a tank of that size.

 

I happened to browse through here and notice this thread. I do not know if it would be legal, but if so, it could resolve your fuel capacity problem and not create a flexible fuel line engineering issue.

Can you build out your front bumper and put a fuel tank there?

I am imagining a heavy duty front bumper mounted to the frame, with a deer-guard round stock frame protecting the tank. Might need two small tanks to allow for lights and radiator air flow.

The obvious issue is the tanks being exposed to damage from the front, but the deer guard would partially mitigate this.

EDIT ADD. A second concern would be effectiveness of headlights. You might need to move the headlights to the front of the bumper assembly since a forward-mounted bumper would reduce the effectiveness of your lights where they are blocked at some angles.

 

You can legally. Period.

 

Truck Bed Doubles As A Fuel Tank With a little change up you could put a goose hookup in this

 

I know for a fact that I have seen generators bumper mounted on work trucks before. With the right fabrication, a bumper mounted fuel tank will be as safe as a fuel tank mounted anywhere else on a vehicle.