Timeline Fixed for Heavy-duty Upgrade


The New Category Development Team has locked in a strict timeline for creating PC-11, the proposed category upgrade for heavy-duty engine oils.

The most telling thing about the schedule set by the NCDT at its March 29 meeting in Chicago is that it has no room for slippage on either engine test development or setting limits for these new diesel oils. Everything must stay on schedule in order to meet a Jan. 1, 2016 deadline for commercial introduction.

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To meet that end date, the American Petroleum Institute must approve the final specification by March 1, 2015, which gives all candidate oils nine months to fairly complete the testing hurdles before their market debut.

At its meeting, the NCDT noted that engine test development timelines will need to be firmed up and made more detailed, especially the development schemes for three new engine test procedures. These include the Mack T-13 for ring, liner and bearing wear; Caterpillar C-13 aeration test; and a Detroit Diesel test for scuffing/adhesive wear.

These detailed plans will help the industry establish test limits as well as select appropriate reference oils. Mack/Volvo Powertrain has indicated that its T-13 test will be ready to go by the end of 2012 with reference oils.

Tests for shear stability and oxidation must be selected, and the NCDT also needs to determine which tests are critical to the category moving forward; otherwise there will be no category unless alternative tests are found. As a last resort, the first license date could slip – but that’s an undesirable outcome.

The team called on diesel engine builders (represented by the Engine and Truck Manufacturers Association, EMA) to offer proposed limits for all new tests. In addition, it said all existing tests which will carry over from the current API CJ-4 category should have their limits defined by the next ASTM Committee D-2 meeting, in June.

There is also the question of where to set PC-11’s high-temperature, high-shear viscosity limits. In fact, two limits might be adopted, so the market would see two oils: PC-11 “regular” and PC-11 “fuel economy.” The latter would have lower HTHS viscosity at 150 degrees C, with both 3.0 mPa.sec and 2.9 mPa.sec under consideration.

There is no clear consensus at this time as to whether the low-vis, fuel economy version will be backward compatible with earlier categories, as will the regular version. That decision is still up for grabs, and will only be decided once the new tests are in place and actual additive/engine oil test programs can begin.

Another critical technical need is to develop a precision matrix for each new engine test, to demonstrate its reliability and repeatability. The NCDT called for the establishment of a task force to do this extremely important task, which likely will require three or four statisticians. The group’s work will begin with designing the matrix in mid-2013, and won’t be complete until the matrix tests are run, results are analyzed and ASTM approves the new tests a year later.

Meanwhile, a task force chaired by Ken Chao of Deere and Co. has begun developing bench tests to evaluate the impact of biodiesel fuels on corrosion, engine deposits, oil oxidation and low-temperature pumpability. Many of these issues were noted in older engine designs but seem to have abated in newer models. Nevertheless, the vintage engines are still in operation and PC-11 oils will be expected to protect them.

The schedule also calls for base oil interchange and viscosity grade read-across test matrixes to be completed by mid-2014, followed by additive technology demonstrations. In the meantime, API must develop user language for the new oil category.

If all goes according to this very ambitious plan, first license date will be Jan. 1, 2016, and mandatory use of the oil in new engines will begin January 2017.

The NCDT meets next on May 3 in San Antonio, and then during the June ASTM D-2 meeting in San Francisco.