Two new diesel engine oils came to market on December 1: CK-4 and FA-4. Formerly known by the oil industry as PC-11 – the 11th upgrade to proposed categories of diesel oil, these two oils are the new quality standard for heavy duty diesel engine oil.
They deliver increased resistance to oxidation – an issue in today’s hotter-running engines, as well as improved resistance to aeration and mechanical shear.
CK-4 is an updated version of CJ-4. It should be used in all engines where CJ-4 was previously recommended. However, CJ-4 oils can still be used during the transition period, which is expected to run through mid-2017.
CK-4 oils are going to be available in 10W-30 and 15W-40 formulations, as well as other traditional viscosity grades. They can be used as the normal fill and top-off on older engines.
It will be the recommended oil for all Cummins engines using Ultra-Low Sulfur Diesel (ULSD).
Fleets currently performing routine oil analysis may notice a change in the oil chemistry, but this is not anticipated to cause any significant issues with mixing CK-4 and CJ-4 oils. It is best to work with one’s oil supplier to ensure a smooth transition.
VISCOSITY
FA-4 a new low-viscosity oil that has potential fuel economy benefits, but may not be compatible with all engines. FA-4 oils will be offered primarily at the 10W-30 viscosity grade, with some 5W-30 formulations available in the future.
The lower dynamic viscosity (how the oil performs at high temperature and shear) leads to thinner oil film thickness and may reduce friction within the engine (which can be significant at certain duty cycles), improving fuel economy.
For each on-highway engine, Cummins will make an individual decision on which oil category it recommends and update each owner’s manual accordingly. However, FA-4 oils will not be recommended for off-highway engines.
It is advisable to reach out to your local engine distributor for questions concerning these new oils and how they may impact your fleet maintenance.
Sources for this article were the following Cummins personnel: Ryan Denton, Ph.D., technical specialist; Corey Trobaugh, Ph.D., technical specialist; and Nate McLeese, oil drain interval subject matter expert. Cummins (www.cummins.com), a global power leader, is a corporation of complementary business units that design, manufacture, distribute and service diesel and natural gas engines and related technologies, including fuel systems, controls, air handling, filtration, emission solutions and electrical power generation systems.
