What is the general shelf life of car engine oil?
1 Answers
Engine oil (fully synthetic, semi-synthetic, mineral oil) generally has a shelf life of 4-5 years. Below is relevant information about engine oil shelf life: 1. Analysis: Under normal circumstances, the water content in engine oil is below 0.03%. When the water content exceeds 0.1%, the additives in the oil (such as antioxidants, detergents, dispersants, etc.) will become ineffective, accelerating the oxidation process of the oil. The organic acids generated by oil oxidation react with acidic oxides in the engine exhaust gas and water, forming inorganic acids. These acidic substances increase corrosion to the engine. Therefore, when engine oil contains more water, its lubricating properties deteriorate, viscosity decreases, leading to premature oil degradation and rusting of parts at best, and severe mechanical failures like engine seizure or bearing damage at worst. 2. Storage method after opening: Seal immediately after opening. After maintenance at a 4S shop or repair shop, the oil bottle cap should be tightened immediately. Note that since the original tin foil seal has been damaged, the remaining cap gasket provides limited isolation. At this time, you can use a clean plastic film folded several times over the bottle mouth for better sealing before screwing the cap back on. For better sealing, wax can be dripped around the bottle mouth cap if conditions permit.
