Can engine oil with a 5-year shelf life still be used in the sixth year?

[DaniellaAnn]

Unopened engine oil can be stored for 5 years, but if the oil has been opened, it can only be stored for 12 months. It is not recommended to use expired engine oil. The national standard for engine oil shelf life is 5 years, although some oils have a shelf life of up to 12 years. Generally, engine oil within 3 years should be fine. Engine oil is not a food or pharmaceutical product, and according to the General Administration of Quality Supervision, finished products with a shelf life exceeding a certain number of years may not need to indicate an expiration date, which is why engine oil often does not have a shelf life label. Additionally, fully synthetic oil has a longer shelf life than mineral oil. To maintain the performance of lubricating oil, it is generally recommended to store it in a cool, dry place to prevent contamination by water or other impurities.

[McDerek]

As an experienced driver who has driven many cars, I really don't think engine oil should be used in its sixth year after a five-year shelf life. Over time, engine oil deteriorates, and the components that protect the engine gradually lose their effectiveness, significantly reducing lubrication performance. I've seen several friends whose cars developed loud engine noises, and upon inspection, it was due to increased wear from using expired oil. Changing the oil is easy—just visit a repair shop and spend a few hundred bucks to get it done. A car is a tool; take good care of it to minimize problems. Don't try to save small amounts of money only to invite big troubles. Regularly check the oil level and color. If it turns black or develops an odd smell, replace it immediately to ensure safe driving.

[SanLucas]

I prioritize safety, and engine oil absolutely cannot be used beyond the sixth year. After the expiration date, engine oil deteriorates quickly, and its lubricating ability declines, leading to engine overheating or increased wear. In severe cases, it can even cause a breakdown. The car maintenance manual clearly states the importance of timely oil changes—following it saves both peace of mind and money. Engine oil absorbs moisture, which can lead to acidic corrosion of components, and its performance is affected by storage temperature and humidity. Don’t risk your engine—changing the oil is a low-cost measure compared to potential repair bills that can run into tens of thousands. Make it a habit to check your vehicle every six months for more reliable performance.

[VanLawson]

When tinkering with your car at home, I know it's not reliable to use engine oil past its expiration date. After five years, the components oxidize and deteriorate, turning darker in color and emitting unpleasant odors, which results in poor lubrication. You can check by opening the engine hood to smell or using a light to inspect the color. Using it in the sixth year is too risky, as it increases friction and makes the engine noisier. Regularly changing to fresh oil is basic maintenance—simple and worry-free, ensuring your car runs smoothly without issues.