Does motor oil expire?

Yes, motor oil does go bad over time. The estimated shelf life for motor oil is 5 years when stored between 45ºF and 80ºF and at a temperature that does not fluctuate significantly. A sealed oil bottle is ideal for maximum shelf life. On the other hand, when motor oil is sitting in an engine it’s required for it to be changed every 12 months. Motor oil can go bad when moisture accumulates inside the crankcase of the engine due to heating and cooling parts after engine operation, which creates water condensation. You do not want moisture to be in your motor oil because it will reduce the performance and protection of the lubricant. So if you are storing a vehicle for more than a year we recommend changing your oil before you start to drive it on the road to ensure maximum protection and peace of mind. I know people like to stock up on motor oil when it’s on sale but buying too much may not be smart because motor oil does expire. Buy only what you need, when you need it!

Factors that affect motor oil shelf life

Contamination – Water intrusion and the migration of water vapor, along with the introduction of foreign materials like cleaning agents and solvents, can cause a lubricant to degrade, resulting in reduced performance.
Temperature – The ideal storage temperature is 32°F (0°C) to 85°F (29°C). Temperatures out of this range can promote water migration, cause additive separation and reduce the effectiveness of additives over time.