YouTube UOA Testing of Amsoil SS vs Penzoil Ultra Platinum on Ram 2500 w/6.4L HEMI

[Pablo]

I did not know that Cu catalyzes oxidation. Being Amsoil SS is very oxidation resistant I'd say it's not of concern.

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Do you know the virgin oxidation number of the SS 0W-40?

 

[edhackett]

I did not know that Cu catalyzes oxidation. Being Amsoil SS is very oxidation resistant I'd say it's not of concern.

I had trouble finding an appropriate article that was not behind a pay wall. This one turned out to be relevant. What was really interesting was the finding that the relative concentration of antioxidant decreased with increasing temperature. At 300C no antioxidant was found. This could be an important factor in Hohn's findings and the fact that we see otherwise clean engines with fully stuck rings.

Effect of iron and copper on the thermal oxidation stability of synthetic hydrocarbon aviation lubricating oil​

The objectives of this study are to (1) characterize properties of lubricating oil using advanced polymer chromatography (APC), gas chromatography/mass spectrometry (GC/MS), pressure differential scanning calorimetry (PDSC); (2) investigate the effect of Cu and Fe on thermocatalytic oxidation of lubricating oil under different temperatures (200, 230, 250 and 300 °C; (3) determine the molecular mechanism of lubricating oil and Cu/Fe under high-temperature. This study highlights the mechanism of thermocatalytic oxidation of aviation lubricating oil at high temperature in the presence of metal catalysts.

Ed