Gasoline stored in cans has a limited shelf life of approximately three to six months depending on the type of gas (ethanol blends generally last up to three months, while pure gas can last up to six). Fuel-stabilized gas can last longer. Old gas cans make great collectibles, but should not be used to store gas since they may have degraded over time forming cracks that can allow fuel to escape. What’s more, old gas may lose its combustive powers due to oxidation and evaporation.