Market acceptance of FA-4 oils has been slow. “Less than 1% of the current overall heavy-duty engine oil market is using FA-4 oils at this time,” says Mark Betner, product manager of heavy-duty lubrication for Citgo. “In addition, one major engine manufacturer factory-fills with API FA-4 engine oil. The use of FA-4 engine oils is currently low due to limited engine manufacturer recommendations. There is also some resistance to the acceptance of low viscosity-fuel efficient oils versus the classic and well-established SAE 15W-40-viscosity grade.”

If you want to test

Betner adds that if fleet managers choose to use an API FA-4 heavy-duty engine oil, they must first know if the engine manufacturer recommends an API FA-4 engine oil for their specific make and model of engine. The primary reason for a fleet to choose an API FA-4 engine oil is most likely to gain improved fuel economy over an equivalent SAE grade of an API CK-4 or CJ-4 engine oil. In other words, if one compares an SAE 10W-30 FA-4 engine oil to an SAE 10W-30 API CK-4 engine oil, the API FA-4 engine should provide an additional fuel economy advantage.

For an in-depth look at the new oil categories, watch our conversation with the experts at Lubrizol.

Managing two oils in shops?

“The assumption with this question is based on a fleet having a few engines that are API FA-4 compliant but other engines in the fleet that are not API FA-4 compliant,” Betner notes. “The result of this situation is that a fleet would need to stock two oils: API FA-4 and API CK-4 oils.”

Tips for using two oils:

• Make sure the storage containers for both API FA-4 and API CK-4 oils are clearly marked and properly identified. Also ensure that engines are clearly marked as to oil requirements.
• Make sure the service technicians in the shop understand the difference in the two oils and which engines must use each product.

“If there is an accidental misapplication, the fleet managers do not have to panic and perform an emergency oil change thinking the engine is in immediate danger,” Betner says. “Instead they just need to understand that an engine that is not API FA-4 compliant should not run for an extended period on the FA-4 engine oil. Always check with your engine manufacturer for the correct engine oil guidelines and recommendations for your engine model.”