Redline 5w-20 / 9,700mi on oil / 2014 5.7 Hemi Durango R/T

I would agree that excessive oxidation is undesirable and to be avoided. But not all effects of oxidation are bad.

Oxidation is the building block of the TCF, and proven to be very beneficial in reducing wear.
This study shows that the establishment of TCF, and subsequent thickening of the film barrier layers from continued lube use, is very directly affecting wear.
- the study showed direct correlation of TCF thickness to wear rates
- the study showed direct correlation of TCF thickness to valvetrain friction reduction
- the study did not show correlation between wear rate changes and viscosity changes
I will remind you all that without correlation, there can be no causation.

Like most things in life, moderation is the key. I certainly don't want my lube to turn into molasses and leave behind pounds of sludge. But study data clearly shows that lubes do very well in extended OCIs because of this TCF; this oxidation barrier that keeps wear rates very, very low under the right conditions. Simply put, some amount of oxidation is very good, too much is very bad.

Engines that run fairly clean, don't have intense "hot spots" which would cause localized coking, etc, can benefit from long OCIs. Nearly all engines I've studied in my database (over 25k UOAs) have shown the effect of lower wear rates as the OCI extends; that is a direct benefit of the oxidation TCF being allowed to mature.
 
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What do the higher universal averages for copper in the 5.7L Hemi come from? In my limited experience reading on this forum, it seems like copper is usually lower unless it's a newer engine with an oil cooler.
 
What do the higher universal averages for copper in the 5.7L Hemi come from? In my limited experience reading on this forum, it seems like copper is usually lower unless it's a newer engine with an oil cooler.
That engine doesn't have an oil cooler. Some have an oil heat exchanger made of aluminum.
 
What do the higher universal averages for copper in the 5.7L Hemi come from? In my limited experience reading on this forum, it seems like copper is usually lower unless it's a newer engine with an oil cooler.
Could be anything including a copper-based sealant. We've seen with some engine families that use coolers or heat exchangers that it chelates from them, but most modern engines have bi-metal bearings, so while historically copper has been a watch for bearing wear (along with lead) it doesn't provide that value now for the most part.
 
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