I acquired a can of Light LME in a can unopened from a friend. The date on it is around 7 years old, it has been in his pantry all these years at room temp. Still good?
I used a 2 year old Cooper's OS lager can once. The yeast in a starter as well. It came out as my Summer Ale that I sent in to Home Brewer TV,which got the full 3 thumbs up. It came out a lot like A Salvator,but lower ABV,same color & flavor.
So go ahead & use it. As long as it's still sealed,it'll be ok...albeit darker in color & flavor.