How long will VP fuels last in an unopened drum?
The length of time the fuel will stay fresh in a sealed drum depends on the fuel itself. A non oxygenated fuel such as C12 should be used within a couple years. I personally have tested some that was eight years old and was fine. As far as an oxygenated fuel I would like to see these fuels used within a year or so. This way you know the oxygen content is still within spec. Both oxygenated and non oxygenated fuels will most likely last longer than I have stated, but I feel that to ensure the best performance following these recommended guidelines will be to your benefit.
Thats right from VP's FAQ.
2-3 yrs on a sealed drum is fine for c12. Eric