Under what conditions should heavy weight oil be used?

Heavy weight oil is best used in warm weather because it has a higher viscosity, which means it is thicker and flows more slowly compared to lighter oils. In warmer temperatures, the oil can maintain an optimal level of lubrication and protection for the engine components without becoming too thin. When oil is too thin, especially in high-temperature conditions, it may fail to provide adequate protection against wear, leading to potential engine damage.

Using heavy weight oil in colder conditions could lead to problems, as its thickness may cause it to flow poorly, resulting in insufficient lubrication during startup. Similarly, while heavy weight oil may technically work in various weather conditions, it is not ideal for cold or snowy weather due to the risks associated with thick oil under such conditions. The key is to match the oil's viscosity with the temperature to ensure the engine runs smoothly and efficiently.