Toyota Valvetrain Wear Test ready for precision matrix testing

Another test was accepted this week for precision matrix testing for the upcoming passenger car engine oil category in North America and Japan known as ILSAC GF-6. The Toyota-sponsored Sequence IVB Valvetrain Wear Test was unanimously voted ready for matrix testing by both the Passenger Car Engine Oil Classification Panel (PCEOCP) and the Auto-Oil Advisory Panel (AOAP) at a joint meeting held in Trenton, Mich., U.S.A. on 14 May.

Teri Kowalski of Toyota, William Buscher of Intertek and Jo Martinez of Chevron Oronite, all part of the test development team, gave presentations and answered questions on the test’s prove-out matrix and readiness for matrix testing during the meeting.

Buscher explained that, as shown by the prove-out data, the IVB test is as precise, if not more precise, than the test it is replacing. During precision matrix testing, wear to the intake lifters will be measured by area loss (measured with a PDI MicroAnalyzer 2000) or volume loss (measured with Keyence VR-3000 3D macroscope, in micrometers). The accumulation of iron in the oil over the course of a test may serve as a secondary pass/fail measure. Three reference oils have been identified for the precision matrix testing: two SAE 5W-30 viscosity grades and one SAE 0W-16 viscosity grade. The test limits still have to be set.

Last month, Lubrizol Corp. joined Southwest Research Institute (SwRI) and Intertek as one of the official labs for the test, although, as Buscher said, it has been contributing since the last quarter of 2014. While Intertek and SwRI have completed their prove-out matrices, Lubrizol has yet to finish. The motion to accept this test for precision matrix testing included the provision that Lubrizol will successfully complete the required prove-out tests. Waiting for Lubrizol to finish its prove-out testing before voting could have added months to the time before the matrix was allowed to start, thus the recent action to proceed with the precision matrix testing.

Kowalski said that a question had been raised prior to the meeting what the course of action would be should the data from Lubrizol fail to align with the data from the other two labs. Kowalski said that the team is confident that the data will align; if not, they will proceed with precision matrix testing without the third lab.

The development of this test was also the introduction of Toyota’s Golden Stand concept. Under this program, SwRI designed and constructed identical stands, eight of which have been distributed among the three labs. TEI supplies the stands, along with special engine hardware provided by OHT. In the prove-out testing, Buscher said, there have been no significant differences among the labs or the stands. Moving forward, Kowalski said, the Test Monitoring Center (TMC) will monitor the labs annually to ensure that the stands remain identical.

Currently, the plan is to license ILSAC GF-6 oils by January 2018. The Toyota Valvetrain Wear Test is the second test to be accepted for precision matrix testing. Six new tests are being developed for GF-6, four of which, including this one, are replacing old tests and two of which are entirely new.