When you see a motor oil viscosity rating, you’re really looking at how easily your oil flows at a certain temperature. For example, at lower temperatures, you want a lower viscosity rating such as a 5W-30. These oils are thinner and better suited for engines in colder climates. This is why your engine starts up faster in winter times if you use a lower viscosity motor oil.
Thicker oils have higher viscosity ratings, which makes them more suitable for higher temperatures in hotter climates. However, it also applies to vehicles carrying heavier loads. A 15W-40 is a thicker, higher viscosity rating that means the oil flows better at hotter temperatures.
However, your vehicle manufacturer includes the correct motor oil grade and rating in your owner’s manual. If you have questions about the right motor oil for your vehicle, don’t hesitate to call our service center at Jim Schmidt Chevrolet-Buick Inc. located in Hicksville, OH.