Evolving oil

By Jami Jones, managing editor

Even with diesel prices remaining at relatively low levels, shaving off fuel consumption remains a top priority for engine makers and oil makers. Going for even greater fuel economy was the nexus of the development of the newest category of engine oil.

For 10 years diesel engine oil had not changed in terms of minimum performance standards set by the American Petroleum Institute. But when the Environmental Protection Agency and National Highway Traffic Safety Administration rolled out new greenhouse gas and fuel economy standards for post-2018 engines, it became evident that a top-to-bottom look at fuel economy savings would have to include engine oil.

That marked the launch of Proposed Category 11 or PC-11.

When the development of the new category started, the possibilities seemed almost endless. Now engine oils will have to get even thinner – or have lower viscosity – to improve fuel mileage, yet still improve on their ability to protect the engine and keep from breaking down because of engine heat. The term 0W, or zero weight, was even being tossed around.

As development and research moved on, it became clear that two new oils would be needed – not just one. The PC-11 category was then split into two subcategories, PC-11A and PC-11B.

The demands on the oil by newer engines will require a different oil than older engines require. One subcategory, called CK-4, will be designed to be backward compatible – where it can be used in older engines. The second subcategory, FA-4, will not be as backward compatible, meaning it will only work with certain engine model years. How many years is the trick.

Dan Arcy, Shell Global OEM technical manager and industry trade association liaison, led the category development team and is confident that the new category standards will provide superior engine protection while contributing to reduced fuel consumption.

The new oils

Now with the new engine oils hitting the shelves in December 2016, drivers have more and more concerns about what has actually changed and what they need to know about the two different oil types. The short answer that truck owners need to know is that CK-4 is a direct replacement for the engine oils you are running now. You will see major oil labels like Shell Rotella, Mobil Delvac and Chevron offering the same blends of engine oils – conventional, full synthetic and synthetic blends – that you are accustomed to using now.

The American Petroleum Institute recommends, to be on the safe side, that you check with your engine manufacturer, or more likely an authorized service center, to verify that CK-4 is the oil that you will be using. You should also be mindful of the recommended viscosity for your engine when purchasing the new oil.

The second subcategory, FA-4, is a different animal altogether. Depending on who you talk to, the oil may have some limited “backward compatibility” or none at all.

The most cautionary of statements comes from the American Petroleum Institute:

“Officially, they are neither interchangeable nor backward compatible with API CK-4, CJ-4, CI-4 with CI-4 PLUS, CI-4, and CH-4 oils. The guidance on API FA-4 use should be heeded: ‘Refer to engine manufacturer recommendations to determine if API FA-4 oils are suitable for use. API FA-4 oils are not recommended for use with fuels having greater than 15 parts per million sulfur. For fuels with sulfur contents greater than 15 parts per million, refer to engine manufacturer recommendations.”’

Using the right oil

The major oil labels contend there could be some backward compatibility into relatively newer engines. But the ultimate decision, they say, is that the decision ultimately lies with the engine makers.

That throws some serious red flags in the minds of many owner-operators, leading to the most pressing question: What happens if I put in the wrong oil?

Pouring the wrong oil in on a top-off – for example putting the new FA-4 oil in an engine recommending CK-4 – will not result in catastrophic engine failure, major oil producers Shell Rotella and Chevron confirm to Land Line. As of press time, Exxon Mobil had not confirmed the same information.

At worst, according to Shell officials, if an oil change results in a full fill of FA-4 oil in an engine needing CK-4, some truck owners could see some oil leaking much the way truck owners did when synthetics first hit the markets and some older engines simply did not respond well to the thinner oils. Rectifying the situation at the new oil change would be fine. They caution that long-term use of the wrong oil would not be good for the life of the engine.

Chevron agrees.

Shawn Whitacre, senior staff engineer with Chevron, said that other common problems when using the lower viscosity FA-4 in a CK-4 recommended engine could be low oil pressure lights, which could trigger other safeguards including having the engine derate. He agrees that prolonged use could lead to premature engine wear and failure.

That makes packaging more important than ever before.

Shell Rotella, Chevron and Exxon Mobil will all be packaging the FA-4 oils in distinctive bottles and containers. Shell’s FA-4 bottles will be set apart with red caps and labeling. Chevron Delo’s FA-4 oils will have yellow caps with FA-4 printed on the cap. Exxon Mobil FA-4 products will have a yellow cap and black label.

Oil drain intervals

The benefits to the new oil categories is potential to extend drain intervals.

The new formulations have been put through the paces with millions of miles already logged on the road. While OEMs have not yet, as of press time, released recommended oil drain intervals, the new oil has performed well in on-the-road testing and shows promise for extended drains.

Mobil Delvac said that truckers dealing with the CJ-4 direct replacement oils should follow the same protocols for extending, or optimizing, oil drain intervals that they followed with the previous oil categories.

“Best practices for evaluating and optimizing oil drain intervals with today’s CJ-4 oils will remain virtually the same when new PC-11 compliant oils are offered. However, with PC-11 compliant oils in use, we recommend establishing a new baseline for oil drain intervals by performing a used oil analysis,” Mobil Delvac’s website states.

“We suggest that fleets work closely with a trusted lubricant partner that can provide the right expertise on the new PC-11 subcategories. It’s important for fleets to determine the best maintenance solutions to help optimize oil drain intervals and protect their vehicles’ engines. We offer a four-step process for optimizing oil drain intervals.”

An oil analysis report allows you to monitor the amount of contamination, the wear rates, and the physical characteristics of a lubricant. Oil analysis is a tool that can allow you to have control over the reactions going on in your engine, giving you a measurement in relation to what the experts in the petroleum industry have determined is normal or abnormal.

Contact the laboratory doing your oil sample and ask them for normal readings for wear metals, and fuel soot for your particular year and make of engine. You can also contact the engine manufacturer for the maximum allowable numbers for your particular engine. That will establish baselines and tolerances so you can monitor the performance of the new engine oils.

Additives and the extras

The age-old debate on whether to supplement your oil with additives or not will likely continue and remains a decision for individual drivers.

The oil makers contend that the formulation of their proprietary oils does not need third-party additives. The oils are formulated for optimum performance without any. Additive manufacturers and truckers with strong opinions and history with various additives will likely disagree.

Oil analysis, warranty specifications, etc., should be considered when adding anything to the as-sold oils. LL