Do engine oils have expiration dates?
The shelf life of an engine oil may vary largely depending on how it is stored, and therefore has no standard expiration date.
An unopened product kept in optimal conditions (shady area, unexposed to sunlight) has a shelf life until five years after the date of production.
Additionally, any leftover oil after initial usage should be kept sealed and used within one year.
If not sealed properly, contact with air may result in oxidation and reduce the performance of engine oil.
Since the sealing cap may not block off oxygen completely, it is recommended that plastic sealing bags are used for extra care.