Can engine oil still be used after being opened for one year?

[LaHayden]

It is best not to use engine oil that has been opened for one year. Once opened, the oil is exposed to air and comes into contact with water molecules and oxygen, which degrades its quality and shortens its service life. Here are some precautions for using engine oil: 1. The storage environment for engine oil must be dry and free from sunlight. If not in use, try to keep it unopened to prevent oxidation. If the oil has been opened, you can seal the bottle opening with a layer of plastic wrap and tighten the cap. 2. Never use expired engine oil. Using expired oil can cause significant damage to internal engine components. Even if expired oil retains some lubricating properties, it cannot maintain its original effectiveness and fails to meet the engine's operational requirements.