It is no secret that the heavy-duty diesel vehicle market has seen a considerable increase in sales in recent years, reaching up to 276,000 units in the United States in 2020. In response, new government Greenhouse Gas (GHG) Regulations are designed to lower carbon dioxide levels and are serving to drive manufacturers and fleet managers to consider the use of lower-viscosity engine oils. However, there is much more than just government regulation to understand and consider when evaluating the switch to low-viscosity engine oils.
Oil Viscosity Trends
In the heavy-duty diesel market, SAE 15W-40 oils were the workhorse viscosity grade for many years. However, the grade has peaked and is forecasted to decline to about 30% by 2029.