Mixed and Boundary Lubrication and GDI/TGDI UOAs

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Site Donor 2023
Apr 4, 2012
Kendall, FL
Taking into consideration that a vast majority of Turbo Direct Injection and Direct Injection vehicles dilute motor oil, and that most UOA of said applications still show low wear metal count (ppm), can we assume that additives have improved to such levels as to becoming the reason why? In other words, Mixed and Boundary films becoming more important in the grand scheme than Hydrodynamic Boundary initial protection?
In engine oil lubrication, corrosion wear (chemistry) matters and adhesion/abrasion wear (physics) doesn't matter , in relative terms. Modern day manufacturing methodology , materials technology and engine designs has shifted engine lubrication regimes on the Stribeck curve to the right towards EHD/Hydrodynamic lubrication regimes, well away from boundary and mixed lubrication regimes , hence further propensity for reducing adhesion/abrasion wear. In relation to thicker engine oil, physics shows a thinner MOFT in thinner oil (of similar additive package) can never produce lesser adhesion/abrasion wear , as is often touted on this board......... being confused with 'wear' per se. But a specific modern day additive package (chemistry) having relatively extra-ordinary efficacy in reducing corrosion engine wear, and to a lesser extent its AW efficacy in reducing adhesion/abrasion engine wear (in boundary lubrication regimes) .......... can drastically change the overall engine wear pattern and proportions....... vis-a-vis a weaker additive package , never mind its physics in MOFT. The same is not true in gear oil lubrication system, and probably a hydraulic system exhibiting insignificant and minimal corrosion wear phenomenon. JMHO.
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