Why do these toolbox/fuel tanks say "for diesel use&quo

I have decided I want to put a tool box in my dually.( one that sets below the bed rails) I noticed these that have a fuel tank in the bottom w/ a tool box in the top. But it says its for a diesel. My question is what would be the difference using it for a gasoline engine...? Thought it would be damn cool....kind of like a fuel cell while still having the tool box I need.






Main reason I am interested is I do use my truck to haul parts or tools occasionally....so the bed actually gets used. Originally thought about buying a toolbox big enough to mount my nitrogen bottle in the bottom and then have a shelf that fit on top to put tools on. But I kind of like the idea of a fuel cell more than the nitrogen bottle.(especially since I dont use the bottle)

I mainly want a tool box to carry a few hand tools in. Thought it would be cool to have a fuel cell/toolbox combo.

beacause of the DOT laws on carring fuel. Most of the toolboxe tanks are used as transfer pumps and have a motor and nozzle. If used for gas it would have to be explosion proof and what not.

They are made out of the same alluminum that fuel cells are though.

I emailed them to see if it can be used on gasoline motor. And if not then why..? Maybe get a discount if buy 2...my buddy Chad wants one for his work truck, but he wants one to carry diesel w/ the detachable pump incase one of the semi trucks runs out of fuel.

the only reason i can think off is that the tank is sitting outside in the sun getting warmer then a regulair tank under the truck , it might need a vapor outlet of some kind and an earthstrap to the metal on the truck .
if the gas should leak out and end up in the bed with some stuff rolling around in it making sparks would be a good reason too , diesel doesnt ignite as easely

i agree on the saftely issue and rules but do we follow rules... i say do it jsut let me know where you are at all times like a gps on okc so that way if he blows up i am not near him... jk man... i never thoguth bout it

gas is most combustible than diesel, and these do not have the slosh stuff in them. neither are recommended for street use anyway. but i know several people that run them instead of the factory tank. my boy here has a 100 gallon on his. you need to take out a loan to fill it up, but it lasts a long time... who cares obout rules later, brian