When should lightweight oil be used in a vehicle?

Lightweight oil is specifically designed to perform well in cold weather conditions. Its lower viscosity allows it to flow more easily through the engine, which is crucial for starting the vehicle and ensuring proper lubrication during colder temperatures. This characteristic enhances the performance of the engine when it is cold, reducing wear and tear during start-up and allowing the components to function smoothly until the engine reaches its optimal operating temperature.

In contrast, using a heavier oil during cold weather can make it difficult for the oil to circulate, potentially causing inadequate lubrication and increased engine wear. Therefore, lightweight oil is the preferred choice as it ensures that critical moving parts receive adequate oil flow and protection in cold conditions.