Do You Need Winter Oil for Your Car?

December 8th, 2023 by

A mechanic is shown checking the oil level of a car before performing an oil change near Mason.

Have you heard the saying, “as slow as molasses in January?” When the temperatures drop, liquids like the oil in your car get thicker and stop flowing smoothly. In Ohio, temperatures often fall well below freezing in winter, so you might be wondering if you need to look for an oil change near Mason to swap to winter oil to protect your car’s engine from damage. In years past, timing your oil changes with the changing seasons was an essential part of car ownership in states like Ohio, but these days, that is not something you need to worry so much about. Modern engine oils are carefully engineered to maintain their viscosity across a wide temperature range so you can use the same oil year round. As long as you have a quality oil in your car—such as the ones we use at our service department—you can hold off on getting an oil change until you have reached the manufacturer-recommended oil change interval, no matter what the weather is like.

Oil Viscosity, The Most Important Number

There is a lot of talk about synthetic versus semi-synthetic versus conventional engine oil, but the single most important detail when choosing an oil for your car is its viscosity number. All engine oils have a viscosity number that is measured by standardized testing devised by the Society of Automotive Engineers (SAE) and overseen by the American Petroleum Institute (API). The higher the viscosity number, the more resistant the oil is to flowing. In other words, water has a very low number, while the proverbial molasses in January has a very high number. The viscosity of an engine oil is commonly referred to as its “weight” or “grade,” with common engine oil weights ranging from 20 to 60.

You might be wondering whether a higher or lower-weight engine oil is better, but the answer is that it depends on the engine in your car. Some engines are designed for a heavy-weight oil, while others run best with a lighter oil. In general, larger and older vehicles prefer more viscous engine oils, but the only way to know the correct viscosity for your car is to check the manufacturer recommendations, which can be found in the owner’s manual and are often printed on the engine oil cap itself. If you have trouble identifying the correct weight, just contact us, and we will be happy to look it up for you. Using oil with the wrong viscosity can result in damage to your engine, as an oil that is too heavy may not be able to work its weight through the engine properly, and an oil that is too light may not provide enough lubrication.

Oil is shown pouring out of a bottle.

Viscosity and Temperature

The basics of engine oil viscosity are fairly straightforward, and as long as you stick to the manufacturer’s recommendation, you’re good to go––at least in warm weather. But what happens when the temperature changes? Standard SAE engine oil viscosity testing is performed at 212 degrees Fahrenheit, simulating the average temperature of a running engine. But any oil is going to be far more viscous at room temperature than at operating temperatures, and it will be more viscous still when you start your car on a frosty Ohio winter morning. This higher viscosity of cold oil is why it is recommended to warm your engine up before you begin driving so that the oil can begin flowing properly and lubricate all the moving parts.

In the old days, drivers in Mason and other cold climates commonly switched to a lower-viscosity oil for winter. This would help the oil flow more easily on startup and better protect a cold engine. However, using lighter winter oil had the downside of often having the wrong viscosity once the engine reached its operating temperature. Further, given the extended oil life of modern synthetic oil, changing it seasonally could mean throwing away perfectly good oil with thousands of miles left in it just because the temperature was changing. To solve these problems, oil engineers invented “multi-grade” oil that can handle both winter and summer without needing to be changed with the seasons.

The Benefits of Multi-Grade Engine Oil

If you look at a bottle of modern engine oil, you likely won’t see a single viscosity number. Instead, you will see two numbers, separated by a “W” and a dash. For instance, take 0W-20 oil, one of the most common engine oil grades for modern vehicles. The second number (“20”) is the standard SAE engine oil weight, measured at 212 degrees Fahrenheit. However, the first number (“0”) is the winter weight, as denoted by the “W” for “winter” next to it. This effectively means that the oil behaves something like a 0-weight oil when cold but acts like a 30-weight oil once it reaches its operating temperature. The end result is that it provides your engine with the protection it needs when you crank it up for the first time on a freezing winter morning, as well as when you’re cruising down Highway 42 through Mason on a warm summer day.

Unlike standard oil weights, which measure the viscosity at a set 212 degrees Fahrenheit, winter weights test at a variety of temperatures, depending on the grade. While a 25W oil is tested to maintain its viscosity at 14 degrees Fahrenheit, a 0W oil is tested at an incredibly low -31 degrees Fahrenheit. In Mason, you will likely never see temperatures that come close to approaching what a modern multi-grade oil is capable of handling, giving you incredible peace of mind that your car will operate correctly all year round. Some manufacturers still recommend using different multi-grade oils depending on the expected temperature range you will be driving in, but for the vast majority of modern vehicles, even our winters are not cold enough to warrant changing your oil to something with a lower viscosity. Those recommendations are for drivers in much colder climates than Ohio.

Oil is shown flowing between pistons.

Make Sure You Use the Right Oil All Year

While some drivers swear by specific engine oil grades no matter the vehicle or insist on changing their oil to a different weight to prepare for winter, you should always use the oil grade recommended by the manufacturer when getting your oil changed. Modern car engines are precisely engineered with tight tolerances and do not react well to large changes in oil viscosity. Sticking to the exact oil grade recommended by the manufacturer is the best way to ensure your vehicle has a long and healthy life, even if you live in an area like Mason with large temperature swings between summer and winter. Modern multi-grade oils can handle far harsher climates than ours, especially if you stick to a high-quality, full-synthetic blend like what we use in our service center.

If you want to learn more about the right engine oil for your vehicle or are in need of an oil change near Mason, pay our certified service center a visit. Our factory-trained technicians know everything there is to know about automotive maintenance, and we only use high-quality parts recommended by manufacturers. We don’t try to cut corners by using generic engine oils because we understand how critical following manufacturer guidelines is when changing your oil. If you want to make sure your car is running on the right oil that will keep it protected no matter the weather, we are here to help.