Gas can in roof rack

Is it ok to carry my 5GL Gas can on my roof rack?

I purchased gas can from harbor freight. It is a metal gas can, does not leak or anything that would make me concerned.

I plan on laying it flat on the rack and using the gas every 5 days just to keep fresh gas in there. My only concern comes from being on top of the truck with the sun shinning on it day in and day out.

Going on a big trip so I just have it as a precaution but i always see people carrying their gas can on the back of the truck and standing up right. I feel as long as it wont leak, it should be fine but I want to ask for your opinion as there are always people smarter than me.

Please let me know what you all think.

Thank you.

 

Google says gas auto combusts at 536F. I don’t think you’ll be anywhere that hot. Most people will say never store gas outside the frame of the vehicle in case of an accident. Can you mount it in your bed?

 

Thank you. My bed is our sleeping area and would prefer not to store gas in there, even if it doesn't leak. I guess I could move it in and out when I need the sleeping area. If the only concern is in case of an accident, the gas being on the roof rack and being in any danger will take me rolling over at least once, probably 5GL of fuel may not be that much of a concern at that point?