With many next generation engines running at higher operating temperatures, engine oil composition needs to change in order to withstand more heat without sacrificing engine protection. Enter the PC-11 oils.
Instead of one category of engine oils, contractors will now have two — often referred to as PC-11A and PC-11B.
PC-11A oils will be replacing the current CJ-4 engine oils. Contractors will be able to buy the same viscosity grades and oil types (conventional, full synthetic and synthetic blends) as they are using now. PC-11A oils will also be backwards compatible to all current vehicles.
PC-11B engine oils will be offered in lower viscosity grades and designed for the next generation engines to help maximize fuel economy without sacrificing protection. PC-11B oils have limited backwards compatibility.
In addition to the improved performance and protection, contractors can expect four other major differences between the new PC-11 oils, which are expected in 2017, and the current engine oils, which saw their release in 2006.
1. Fuel economy
PC-11A oils are being referred to as High HTHS (High Temperature High Shear viscosity) while the PC-11B oils are being referred to as Low HTHS oils. the Low HTHS oils are being designed for higher fuel economy than the current CJ-4 and even the PC-11A oils through the use of thinner viscosity fluids.
2. Shear stability
Shear stability is the ability of the oil molecules to resist shearing under severe stress inside an engine. The new PC-11 standards call for improvements in shear stability compared to the CJ-4 oils. More stringent shear stability test limits will validate that each oil's shear stability meets the new guidelines.
3. Oxidation stability
Oxidation is one of the primary causes of oil breakdown and is accelerated by higher operating temperatures. Since the next generation of engines are designed to run at higher temperatures, the PC-11 standards are requiring the oils feature improved oxidation stability compared to the CJ-4 oils.
4. Aeration control
Finally, the new oils will have to pass a new aeration test in order to make sure they are effectively controlling aeration, which can impede an oil's ability to protect an engine.
Information taken from whatispc-11.com.