Thanks for the cautions folks. I look at this as better/safer than the four five gallon jugs I used to carry on the front of the trailer. Debris would punture them more easily and they weren't as secure compared to the SAE 5 bolts holding the tank down. Regarding expansion, the manufacturer suggests leaving a good gallon of space for expansion or 2 inches from the fill. Never heard about tracks not allowing outside fuel before. Not sure why water and rust would be more of a risk than in any other metal fuel tank...?