Inline with the forthcoming API CK-4 diesel engine category, the oils must meet Cummins Engineering Standard [CES] 20086, which is an updated version of CJ-4 (CES 20081), and is recommended for all engines using Ultra-Low Sulfur Diesel (ULSD) and CES 20081.
CES 20086 is going to be available in 10W-30 and 15W-40 formulations, as well as other traditional viscosity grades. It can be used as the normal fill and top-off on older engines, and will have a higher oxidation capacity, to handle the increased heat load in todays hotter-running engines. It will be the oil of choice for most Cummins engines.
FA-4 (CES 20087) is a new low-viscosity oil that has potential fuel-economy benefits, depending on duty cycle, but may not be compatible with all engines. FA-4 (CES 20087) will be offered primarily at the 10W-30 viscosity grade, with some 5W-30 formulations available in the near future. The FA-4s lower dynamic viscosity (how the oil performs at high temperature and shear) leads to thinner oil film thickness, and reduces friction within the engine (which can be significant at certain duty cycles), improving fuel economy by some margin.
For each 2017 engine, Cummins will make an individual decision on which oil category it recommends, and update each Owners Manual accordingly. The on-highway 2017 X15 will be compatible with CES 20087 10W-30 oil, but will recommend CES 20086 10W-30 oil.
Ryan Denton, Lubricant Technical Specialist, Cummins, told OEM/Lube News "We plan to publish our CES 20086 and CES 20087 standards in the next month and begin the registration process shortly after publication".
