Can I Use 10W40 Instead Of 15W40 – The Definitive Cold Start & Engine
In short, yes, you can often use 10W-40 oil in place of 15W-40, especially if you live in a colder climate. The 10W-40 will flow better during cold starts, providing faster lubrication and reducing engine wear. However, for certain heavy-duty diesel engines, high-mileage vehicles, or in very hot weather, sticking with the manufacturer’s recommended 15W-40…