It depends.
Various factors affect how long before any oil breaks down. Whether inside your engine or in a bottle on a shelf, over time oil degrades and no longer protects parts from wear and tear. Once in the engine, motor oil should be changed at least once a year, regardless of mileage.
The shelf-life of a sealed bottle of oil can be two to five years, depending on the producer. This depends on temperature and how the oil is stored.
Unless you are 100% positive no dust, debris, or moisture made it into an opened bottle of oil, don’t use it. Even if it’s an expensive bottle of synthetic oil, the cost will pale in comparison to the engine repair cost if you top it off with contaminated motor oil. Always recycle oil or hazardous waste responsibly.
Do Synthetic Oil Containers Have Expiration Dates?
Again, it depends. While some producers do add a “Best By” or expiration date, most add the production date to the bottle. John Paul from Pennzoil technical support says a JAN2323 production date on their bottles refers to January 23, 2023.
How Often To Change Synthetic Oil
Yep, it depends.
Under “normal” driving conditions, synthetic oil can go 10,000 to 15,000 miles, or six to 12 months, between changes. Follow these guidelines for changing oil under these extreme driving conditions:
Short trips
If you’re commuting less than 10 miles a day, oil cannot get warm enough to burn off moisture and impurities. Change oil every 5,000 miles or every six months, or sooner.
Climate
Living in an area with extreme temperature fluctuations (0 degrees in the winter to 100 degrees in the summer) reduces motor oil’s ability to protect your engine. Change oil right before and right after winter and summer and after no more than 5,000 miles.
Harsh driving conditions
- High-speed highway driving: Change oil every 6,000 miles or six months.
- Driving on dusty, gravel, sandy or salty roads: Change oil every 3,000 miles, and check the air filter as well.
- Driving at low speeds for long distances: Change oil every 3,000 miles, or three months.
- Stop-and-go driving or idling for long periods: Change oil every 4,000 miles, or four months.
- Towing a trailer: Change oil every 4,000 miles, or four months — more frequently in sandy, or muddy conditions.
When in doubt, always follow the manufacturer’s recommended service intervals or sooner. And definitely change when the oil life monitor reaches 25%.
Synthetic Oil Change Cost
The high cost of quality base oil, expensive refining processes and pricey additives make synthetic oil more expensive than conventional oil.
“But those costs are coming down,” says Pyle. “You can purchase base oil and full synthetic in a quart or gallon for only a few dollars difference. Synthetic is becoming the norm and oil companies are making the process easier and cheaper, so it will continue to become less and less a price difference.”
If you aren’t DIY’ing your oil changes, know that many repair shops offer discounts on oil changes. Look for promotions and coupons.
DIY Oil Change
Most shops don’t charge a whole lot more to change your oil and filter than you’d pay for the supplies. So why DIY? If you have the tools, DIY oil changes save time and may save you some money. That, combined with the satisfaction of changing oil yourself, are excellent motives.
About the Experts
- Chris “Moose” Pyle is a master-certified technician with 20-plus years of automotive experience. He has also worked as an expert for JustAnswer, the expert on-demand platform, since 2006.
- Duane “Doc” Watson is a technical trainer at Bosch Mobility Aftermarket. He has more than 45 years of experience in automotive repair, has trained thousands of technicians and earned many industry awards, including Chevrolet Technician of the Year and Buick Service Master of the Year.
