Keeping your car’s motor running wouldn’t be possible without quality engine oil. This essential fluid is designed to lubricate engine components to avoid the need for auto repair due to overheating, corrosion, and premature wear. It also helps promote fuel efficiency, clean engine parts, and reduced emissions. To maximize these benefits, though, drivers need to not only invest in regular oil changes but also make sure the fluid they choose has the proper viscosity. Here’s a closer look at engine oil viscosity and why it matters. 

How Does Oil Viscosity Affect Your Engine?

Viscosity refers to how much resistance the oil faces as it moves through the car. For example, low-viscosity engine oil will flow through the engine faster to help minimize friction, reduce fuel use, and prevent overheating. Low viscosity is also critical in the winter, as it will be less likely to thicken up. Thicker oil can make cold starts tougher and cause progressive engine wear. 

By contrast, solutions with higher viscosity can provide a thicker layer of support between interior components to help prevent wear in higher temperatures—especially for commercial semi-trucks with larger, more complex engines. Higher viscosity also helps minimize oil burn-off in hotter climates since it's harder for the thicker fluid to evaporate.

How Is Viscosity Measured?

Optimizing engine performance and minimizing the need for auto repair requires motor oil that is neither too thick nor too thin. To help you get the perfect fit, oils are categorized by a wide range of viscosity ratings that follow a “#W-##” format. 

The number before the W determines how quickly the fluid will flow in standard winter temperatures. The lower the number, the quicker it will flow. 

The numbers following the W rank the oil’s viscosity at an engine’s standard operating temperature. The lower this figure, the less resistance it will face. 

For example, a “5W-30” oil will provide less resistance at a cold start than a “10W-30” formula. A “5W-20” formula will be thinner than a “5W-30” product when the engine is running at its standard temperature. 

You can consult your vehicle’s owner’s manual to determine which viscosity rating is best for your engine. 

Are Multi-Grade Synthetics Beneficial? 

Multi-grade formulas blend additives or synthetics to create a more versatile oil. Specifically, these products can maintain proper viscosity in a wider range of temperatures and operating conditions. While these formulas tend to cost more than standard motor oils, they offer better year-long protection for vehicles operating within climates that change frequently and can help drivers avoid vehicle damage from improper oil viscosity.

If your vehicle's oil causes problems on the road, Tomah Wrecker & Repair LLC is here to help. Serving motorists in Monroe County, WI, this auto repair center is equipped to perform oil changes using the proper formula for your car. To learn more about their services, visit this towing company and auto shop online. If you’d like to request 24-hour roadside assistance or towing service, call (608) 372-2550.