You may need to reconsider using that old can of oil in your car. A study by The Motor Oil Geek on YouTube reveals that expired engine oil can be hazardous to your engine. In the video, host Lake Speed Jr. investigates whether shaking old oil could restore its usability. He examines two sealed oil containers—one plastic and one metal—to determine if shaking could revive them.
The laboratory results are not unexpected. Both the 20-year-old Valvoline oil and the 50-year-old Mobil1 exhibited significant oxidation, regardless of being shaken. This indicates that the oil, along with its additives such as Zinc, Phosphorus, and Sulfer, has degraded chemically to a point where it can no longer adequately lubricate an engine.
The Valvoline oil in the plastic bottle was particularly problematic, showing signs of water contamination accumulated over twenty years due to the container's heating and cooling cycles. It is strongly advised not to use that old oil bottle in your garage, even for topping off.
Parts suppliers like Autozone and CarParts.com suggest that most motor oils have a shelf life of about five years. Beyond this period, oxidation starts to degrade the lubricant's quality. If you're unsure about your oil's condition, Speed Jr. has another video demonstrating how to assess your oil's health at home without specialized testing equipment.
