That's only 2.5 years old. I'd use it without hesitation.
Typically, three years is certainly OK. Even five years is OK for a sealed container for most decent brands. After that, you risk some of the additives falling out of suspension? Perhaps Johnny could add some details?
But for $11 for five quarts and only 2.5 years old, I'll take it off your hands if you don't want it!