How long is gas good for in a 50gal drum? A friend who seems to know a few things told me it won’t go bad if it’s not opened that it’s a myth it will go bad closed. Is that correct? I have a few drums I used for KOH gas , one for tractor diesel and spare rv fuel... but I never tried leaving gas in one long. I need to refill my barn diesel drum, I’ll fill both gas drums if it will last. But if one will go bad before I burn it all up in sxs’s then I won’t waste my time. I guess I use about 25 gallons of gas every month or more riding sxs.