What’s Next After FA-4?
API CK-4 is said to be the most robust diesel engine oil performance category ever developed. The FA-4 category takes that a step further, delivering a 2-3% improvement in fuel economy, as its lighter viscosity (10W-30 and 5W-30) is easier for the engine to pump internally.
Most of the previous category changes were the result of emissions restrictions. In addition to the traditional measurables such as particulate matter and oxides of nitrogen, there are now greenhouse gas emissions regulations to meet as well.
“We can only confront carbon dioxide emissions through improvements in fuel economy, and oil will have a role to play there,” says John Pettingill, Petro-Canada Lubricants product specialist.
Truck and engine manufacturers are focused on providing customers fuel-efficient, durable, low-emission engines, and this will continue for the foreseeable future. At this time, none of the major truck or engine manufacturers has requested a new performance standard. But that doesn’t mean lubricant suppliers are sitting back taking it easy.
“Shell Lubricants will continue to see a focus on fuel economy,” says Dan Arcy, global OEM technical manager at Shell Lubricants. “Oil can help provide a fuel economy benefit, and we have demonstrated that lower viscosity oils can help provide that without any compromise in engine durability.”
Petro-Canada Lubricants, for example, has already begun testing full-synthetic 0W-20 diesel engine oils in current engines. “To realize even better fuel economy benefits, you’d need to lower the High Temperature High Shear (HTHS) limit to somewhere below 2.9 centipoise [cP – a measure of viscosity],” Pettingill says. “If we can demonstrate that we can make a 0W-20 oil that can protect as well as a 10W-30 or a 15W-40 and still provide the fuel economy benefits, that would be a real step forward in the future of engine oils.”
According to Arcy, a 0W-20 diesel engine oil is feasible to make today, and some OEMs in Europe are factory-filling with 0W-20. “The engines must be specifically designed to use a 0W-20 diesel oil,” he says. “Where we go from here depends on what changes OEMs make to their future engines.”