How cold weather affects motor oil

Everyone feels a bit sluggish in the dead of winter. Your car’s engine and oil are no exception! When the temperature drops, motor oil becomes thicker. This makes the oil flow more slowly through the engine and around the engine block, putting more strain on the battery to get things going—which is already working harder to combat the cold.

That’s why we recommend you let your engine run for a few minutes before driving in the winter: it gives the engine time to reach operating temperature.

However, letting your car idle for ten minutes will not help. The first few minutes after turning on your vehicle in winter start warming the motor oil up and lubricating engine parts. Only once you start driving does the oil reach its optimal operating temperature.

Keep in mind, too, that your engine needs more time to warm up in winter, which increases your fuel consumption. Don’t push your engine too hard when you start driving: cold motor oil can’t properly lubricate your engine. This increases the friction between all the moving parts and the transmission, which can lead to engine damage. Even though most modern vehicles can handle cold starts, pushing any vehicle too hard while the engine and oil are still cold can lead to issues.

If you notice the following symptoms in winter, you’re likely having an issue with your motor oil:

• ticking or knocking sounds from the engine, especially when starting up
• reduced fuel efficiency
• engine taking much longer to start

You can prevent these issues by choosing a motor oil better suited to your vehicle and Canadian winters.

Picking the right oil for winter driving depends on your vehicle’s make and model, your driving style, and the environment where you drive. To make the correct selection, you need to understand viscosity ratings.

Viscosity ratings show you how the oil flows in winter and at operating temperature. For example, “5W-30” is a viscosity rating. “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. Common viscosity oils for winter are 0W-20, 5W-20, or 5W-30.

But don’t assume that lower is better in the winter: a lot depends on your engine’s construction.

The four main types of engine oil are conventional, synthetic, synthetic blend, and high mileage. Each type has its own viscosity rating. Synthetic oils work best in the cold because they have a lower pour point (the lowest temperature at which the oil flows).

You can also take a look at multi-grade oils, which can be used year-round (depending on average temperatures in your location). These oils are made with chemicals known as viscosity index improvers, which allow the oil to run thinner in the cold and thicker in the heat.

Visit this article for more advice on choosing the right motor oil for your car. Your owner’s manual will also recommend an ideal oil for your particular vehicle model.

No matter what type of motor oil you use, your vehicle needs regular oil and oil filter changes to perform its best. This interval can vary depending on your driving habits and the health of your engine and its oil, but it is typically every three or six months. Newer vehicles may have an oil life monitor to alert you when the oil and oil filter should be changed. Read our article on how to do an oil change for more guidance.

Another way to protect your engine in the winter is to fill it up with some antifreeze/coolant. This will stop the water in your car’s engine from freezing in the cold, helping the engine maintain an even temperature. You can learn more about antifreeze and how to incorporate it into your winter maintenance routine.

For any questions about choosing motor oil or more tips on protecting your car during winter, visit a NAPA Auto Parts store to chat with an expert.