news image

What is the difference between CK-4 and FA-4 oils?

Q. What is the difference between CK-4 and FA-4 oils?

A.  The primary difference in the two categories of PC-11 heavy duty oil is with backward compatibility. API CK-4 oils will support virtually all high-speed four stroke cycle diesel engines – including older engines that were using CJ-4, as well as new engines that are currently being developed. Use of API FA-4 oils will be OEM dependent and may not be suitable for use in older diesel engines. This category will focus on the next generation of diesel engines that are currently in development to deliver greater fuel efficiency. Other differences include:

  • PC-11A (Licenses as API CK-4)
  • Viscosity grades include both SAExW-40 and xW -30 engine oils with >3.5 cP HT/HS viscosity
  • Higher level of wear and oxidation protection versus API CJ-4 oils
  • Improved shear stability
  • PC-11B (Licenses as API FA-4)
  • Improved fuel economy performance versus API CJ-4 oils
  • Applies only to SAE 10W-30 and SAE 5W-30 viscosity grades that have are between HT/HS viscosity in the range of 2.9 to 3.2 cP

If you need further clarification please contact our Certified Lube Specialist, Jude Hupp, at 661-327-4900.

Wholesale Fuels, Inc.

2200 E. Brundage Lane             PO Box 82277

Bakersfield, CA 93307               Bakersfield, CA 93380

Office   661-327-4900