As you probably know, the European Automobile Manufacturers Association or ACEA, the trade group representing the top 15 European automotive OEMs, has announced plans to publish new oil sequences in 2021. But you may still wonder:
What is driving these changes?
What do they mean for producers of lubricants for the European market?
And how is Oronite interpreting these revised standards?
First, a bit of context. The European Union has some of the world’s strictest regulations on fuel economy and vehicle emissions. Automotive OEMs have had to make significant changes in engine design to meet these standards, including reducing engine sizes, adding turbochargers to maintain power, and introducing Direct Injection (DI) to boost fuel efficiency.
These changes in engine design create a tougher environment for engine oils, with more intense power density and higher operating temperatures. Modern engine lubricants must be formulated to deliver optimal performance under these pressures. That is the chief driver for the new ACEA specifications – to ensure full protection for the newest generation of engines on the market.
Unlike previous updates, the ACEA has decided this year to stagger the releases of the new oil sequences for gasoline and Light Duty Diesel Engines (LD) and Heavy Duty Diesel Engines (HD). The new LD oil sequences were released in April 2021, with the new HD oil sequences expected later this year. Current ACEA 2016 sequences will expire two years after launch of the new oil sequences, after which oils based on the 2016 standards can no longer be marketed.
Now, let’s look at the LD and HD categories one by one.
new ACEA light duty oil sequences
Key changes to watch
ACEA A3/B3 categories will be removed; alternative recommendations will be ACEA A3/B4.
ACEA A7/B7 will be introduced as an upgrade for oils with a conventional chemical box. It includes the same performance testing as for ACEA C6 (except fuel economy).
ACEA C1 category will be removed.
ACEA C6 will be introduced to provide additional performance for today’s engine technology. It addresses fuel economy, LSPI protection, engine chain wear protection and turbocharger deposit control.
ACEA plans to further specify the ASTM D4739 test method for Total Base Number (TBN) in the new oil categories. ACEA believes that this test method results in more meaningful TBN.
New testing requirements:
Turbocharger Compressor Deposits (TCCD)
LSPI (Sequence IX)
Chain Wear (Sequence X)
Fuel Economy (JASO FE)
Test phase out and replacement:
Low temperature sludge: Sequence VH replaces Sequence VG.
Piston deposits: VW TDi3 replaces the VW TDi2 test to match newest engine technology.
Engine sludge: Daimler M271 EVO test has replaced M271.
Improved oxidation stability to compensate for increased thermal stress.
Replacement of the OM501LA piston cleanliness test, which is being phased out.
Two new low viscosity oil categories to support improved fuel economy.
New low viscosity F class oil categories to align with the API FA-4 oil specification. These oils have an HTHS between 2.9-3.2 mPa.s (SAE xW-30 grades, x = 0, 5 or 10).
ACEA does not plan to change E4 and E7, which are still in use outside of Europe.
New testing requirements:
ACEA has selected the ASTM Volvo T-13 engine test to evaluate oxidation resistance for all aftertreatment compatible oil categories. Introduced with the US API CK-4 and FA-4 oil specifications in December 2016, the Volvo T-13 test is a single stage 360 h engine test running at a 130°C oil gallery temperature.
ACEA will adopt the new ASTM Caterpillar Oil Aeration test (COAT) in the new Oil Sequences.
The Volvo T-13 and the COAT test will be introduced in oil categories E8, E11, F8 and F11.
The introduction of these new tests will result in a severity shift that requires renumbering of oil categories.
For F8 and F11, two additional bench tests – one for bearing wear and one for ring and liner wear – are under development to evaluate wear resistance of low viscosity oils in the low-soot operating conditions of modern Heavy Duty Diesel Engines.
Daimler has developed a successor for the Mercedes-Benz OM501LA test based on the OM471 engine. This test primarily focuses on piston cleanliness, liner and valve train wear and oil oxidation in the latest Euro VI engine technology. ACEA intends to introduce the OM471 as a CEC approved test. This test primarily targets the higher performance oil categories E8, F8, and eventually E4. Plans calls for tests to assess piston cleanliness performance categories E7, E11, and F11.
The development of the two new low soot wear bench tests (LSWT) targeted for F8 and F11 has been delayed. ACEA has postponed the release of these new oil categories. Eventually, ACEA must find an alternative solution for testing wear resistance in low viscosity oils. The current plan is to release the new ACEA HD Oil Sequences without the oil categories F8 and F11.
ACEA heavy duty sequences overview
the oronite view: how these changes affect current and future products
Light Duty: The magnitude of the ACEA 2021 LD sequence changes will vary depending on the category. However, we see some general implications for current and future lubricant development:
For current products that meet the ACEA 2016 LD release specifications, the addition of valve train wear performance, through Sequence IVA or IVB, can address the ACEA 2021 requirements. Sequence VG, M271, and TDi2 tests can be used instead to evaluate current products for ACEA 2021 performance. However, since these engine tests are being replaced, new oil developments will require the completion of the latest engine tests (Sequence VH, M271 EVO, and TDi3), which is already the case for the new oil categories A7/B7 and C6.
For the newest oil categories A7/B7 and C6, performance screening will require a variety of tests focusing on different performance criteria:
Sequence IVB for valve train wear performance (no grandfathering of Sequence IVA results will be accepted)
TDi3 for piston cleanliness (grandfathering of TDi2 will be accepted)
Turbocharger Compressor Deposit Test (TCCD) for turbocharger cleanliness
Sequence IX for LSPI performance
Sequence X for chain wear
JASO FE Fuel Economy only for the C6 category
Heavy Duty: As with the Light Duty release, the extent of changes in ACEA 2021 HD sequences depends on the category:
For current products meeting E4 and E7 per ACEA 2016 release, the upgrade to ACEA 2021 will almost be automatic. No new test is included in the new release, although there are some new limits in foaming tendency (ASTM D892 and ASTM D6082) and elastomer compatibility (CEC L-112).
For the new oil categories, the performance upgrade from E8 and E11 to E6 and E9 becomes more significant, New tests looking for improved piston cleanliness (OM471), oxidation resistance (Volvo T-13) and aeration performance (COAT) are required.
keeping up with evolving standards
The step-up performance demands of the new ACEA 2021 release underscores the need to bring products to market that meet the standards of The European Engine Lubricant Quality Management System (EELQMS). Avoid using crankcase lubricants with unsubstantiated claims that do not follow Industry Codes of Practice and lack adequate supporting data. Although ACEA claims are self-certified, any ACEA claim requires the oil marketer to sign a Letter of Conformance with EELQMS quality standards.
All these changes highlight the importance for all industry stakeholders to keep offering products that meet the requirements of current vehicle fleets, while developing new lubricants that will keep up with the evolution of engine hardware – the main reason for the introduction of new ACEA oil categories.