API Approves Development of PC-12 Diesel Engine Oil Grade
Earlier this year, the Engine Manufacturers Association (EMA) asked the Diesel Engine Oil Advisory Panel (DEOAP) of the American Petroleum Institute (API) to initiate the development of a new class of diesel engine oil to coincide with the implementation of the new EPA and CARB HD highway regulations. Last week, the development phase of the tests was launched, with the first license of petroleum products under the standard expected no later than January 1, 2027.
The EMA approached the panel in March 2021, which led to the creation of a new Category Assessment Team (NCET) upon request. The NCET voted last week to recommend the panel proceed with the development of the proposed category – PC-12. At the ASTM D2 meetings in Anaheim, CA, the DEOAP then approved the recommendation to create a New Category Development Team (NCDT). API Lubricants Group reviewed this request and voted to establish the NCDT, officially initiating the PC-12 test development phase.
The new category is requested with the following improvements:
- Increased oxidation performance
- New wear test capability
- Added lower viscosities
- Improved post-processing capability
- Extension of elastomer compatibility
Obsolescence of engine tests (testing equipment becoming unavailable) will also be taken into account. The T-11 and T-12 tests are probably not available for PC-12. The Category Life Oversight Group (CLOG) will continue to assist with technical evaluation and statistical support for correlations where appropriate. The NCDT will develop a replacement for the T-11 as needed.
The date for the first API license application is no later than January 1, 2027. This coincides with the planned implementation date of 2027 for the EPA and CARB HD road regulations. The recommendation asks to consider December 1, 2026 as the date of the first licence. This is similar to the PC-11 licensing schedule that resulted in the CK-4 and FA-4 APIs.
The potential advantages of diesel engines are:
- Enables new engine technologies that are expected to experience higher brake mean effective pressure (BMEP) and customer demands, as well as meet anticipated regulatory requirements for useful life and extended warranty periods.
- Supports fuel economy requirements for certain engine models.
- Supports new elastomers used in modern engines.
Fleets and drivers should expect improved performance from oils, which promotes increased engine durability and helps meet regulations. This can result in lower cost of ownership.
Potential environmental benefits include limited SAPS (sulfated ash, phosphorus, sulfur) that will support engines that meet stricter environmental regulations on reduced emissions. Longer oil change intervals may be possible, which supports durability goals.
The current subclass C will retain backwards compatibility and the new subclass F is intended to replace FA-4 and does not need to retain backwards compatibility. The potential for existing engine trials to become obsolete will be addressed as needed.