Does Engine Oil Expire?

A vehicle’s fluids, including its engine oil, are crucial to its overall health. If you don’t check and change them often enough, your vehicle is at risk of serious damage.

If this article, we go over the most common types of engine oil, how to choose the right oil for your needs, how long engine oil typically lasts, and how you can tell if your oil is expired.

Picture of test of engine oil

Types of engine oil

The four main types of engine oil are conventional, synthetic, synthetic blend, and high-mileage.


  • Best for simple and/or older engines and regular driving styles


  • Contains higher performing additives than conventional oil
  • Resists oxidation better than conventional oil

NAPA Conventional Motor Oil

Starting at 6.50 $

Shop Now

NAPA Synthetic Motor Oil

Starting at 10.00 $

Shop Now

Synthetic blend

  • A mixture of conventional and synthetic base oils
  • Resists oxidation better than conventional oil


  • Usually a full-synthetic oil or a synthetic blend
  • Best for vehicles with over 120,000 km
  • Formulated to reduce oil burn-off and prevent oil leaks in older engines

Valvoline Motor Oil Full Synthetic

32.99 $

Buy Now

Pennzoil High Mileage Motor Oil

54.29 $

Buy Now

Choosing the right type of engine oil

The right type of engine oil depends on many factors, including your vehicle make/model, your driving style, and your environment. You also need to know what oil viscosity you need.

The codes 0W-20, 5W-20, 5W-40, and 15W-40 are all examples of oil viscosity ratings. The “W” stands for winter. The first number refers to the oil flow in cold weather, while the second refers to the oil flow at operating temperature (measured at 100°C.) The lower the number, the less viscous the oil and the quicker it will flow.

For example, a 5W-30 oil will flow faster at start-up than a 10W-20 oil, but the 10W-20 oil will flow faster once the engine reaches operating temperature.

Synthetic and synthetic blend oils are typically more viscous than conventional oils.

Check out this article for more on the differences between conventional vs. synthetic oil.

How long does engine oil last?

The shelf life of engine oil can vary. Unopened conventional engine oil lasts about five years. Most synthetic, synthetic blend, and high-mileage oils last seven to eight years when sealed. Once opened, all engine oils last about a year.

Your owner’s manual will specify how often you should change your oil. For most vehicles, this is at least every six months or every 5,000 km to 8,000 km. If you use a synthetic oil, you can likely stick to the higher end of this range.

Over time, the oil will break down, become less viscous, and be less efficient at lubricating the moving components of your engine. If you rarely drive for more than 20 minutes at a time, your oil may expire faster because the engine won’t get hot enough to burn off moisture. This can cause corrosion, potentially damaging your engine.

Even if you only drive on rare occasions, change the oil in your engine at least once or twice a year.

How can you tell engine oil has expired?

Aside from checking the expiry date on the container, you can evaluate the colour and consistency of your oil to see if it’s expired.

Check your engine oil using the dipstick and a cloth. You can wear nitrile gloves to keep your hands clean, but it’s not necessary. Fresh oil is usually a light amber colour or translucent. If it’s expired, it will be dark brown or black. If you see a thick, milky brown substance, your engine oil may have mixed with your coolant. If the oil looks separated, thick, or solidified, change it ASAP.

Oil Drip Pan

59.99 $

Buy Now

Nitrile Gloves

18.99 $

Buy Now

Changing your oil at home

Regardless of the type of oil you use, the method to change your oil is the same. To replace your oil and filter at home, follow this guide.

If you have any questions about engine oil or oil changes, visit your local NAPA Auto Parts store to speak with an expert.

Leave a comment

Your email address will not be published.Required fields are marked *