Engine Oil Tips – What is Viscosity?

At MOTUL, we understand that choosing the right engine oil can be confusing, especially with so many technical terms thrown around. One of the most important, and often misunderstood terms is viscosity. So, what is viscosity, and why does it matter for your engine?

What is Engine Oil Viscosity?

Viscosity refers to how thick or thin an oil is and how easily it flows at a specific temperature. It’s a measure of the oil’s resistance to flow. A higher viscosity means the oil is thicker and flows more slowly, while a lower viscosity means it’s thinner and flows more easily.

In simple terms, it’s how well the oil can lubricate, protect, and maintain its performance under different operating conditions.

Understanding Oil Grades – What Do the Numbers Mean?

You’ve probably seen oil grades like 5w-30 or 10w-40 on engine oil bottles. These numbers are defined by the Society of Automotive Engineers (SAE) and represent the oil’s viscosity rating.

Let’s break down an example: 5w-30

"5w" – The "W" stands for winter. This number shows how the oil behaves at cold temperatures. The lower the number, the better the oil flows when the engine is cold, making cold starts easier.

"30" – This number indicates the oil’s viscosity at the engine’s normal operating temperature. Higher numbers mean thicker oil at high temperatures, which can offer more protection in extreme conditions.

Why Viscosity Matters

Choosing the right viscosity is essential for:

✅ Protecting your engine – The right oil ensures proper lubrication and reduces wear and tear.

✅ Fuel efficiency – Lower viscosity oils can reduce internal friction, improving fuel economy.

✅ Cold starts – Oils with lower winter viscosity help your engine start more easily in cold weather.

✅ Temperature performance – The correct viscosity ensures consistent performance across different climates and driving styles.

MOTUL Oils – Engineered for Precision

MOTUL offers a wide range of premium engine oils tailored to meet the specific needs of your vehicle—whether it’s a high-performance sports car, classic motorbike, or daily driver. Our products are rigorously tested and formulated to deliver optimal viscosity, exceptional protection, and long-lasting performance.

How to Choose the Right Oil for Your Vehicle

1. Check your vehicle manufacturer’s recommendation – Always refer to your owner’s manual.
2. Consider your climate – Colder climates may benefit from lower winter viscosity oils.
3. Think about your driving style – High-performance or heavy-load driving may require higher viscosity oils for added protection.

Not sure which MOTUL oil to choose? Use our Oil Selector Tool or speak to your nearest MOTUL expert.