gas cap vent

[chumbucket]

I would think that if you use the vented filler that I showed and run another vent line from that filler to the outside as a second vent, it would probably solve the problem when sitting on the trailer. This way, with the filler in the from of the tank he could raise the tongue of the trailer up and it would still vent from the larger filler hose in the front of the tank.