OVERKILL
$100 Site Donor 2021
But your first run of HPL was 1.25ppm/1000 miles. You have a single run of Valvoline Restore and Protect at 0.94ppm/1000 miles, which was effectively identical to your Valvoline Extended Protection run, which was also an API additive package lube. These are all insignificant; these are all extremely low uptake rates if you look at some of the others in my post. Look at the swings in #2 for example.From my data, it suggests that a 10k HPL oil interval even with a 5k oil filter change, the iron wear rate was double that of Valvoline Restore and Protect. A 10k oil interval contains higher accumulative levels of Fe that cannot be removed by a new filter but only by a full oil change.
And yes, the range of particles able to be seen by spectrography is below the filtration range captured by typical oil filters, so a filter change, aside from some dilution from make-up oil, where applicable, won't have an appreciable effect on concentration visible to a used oil analysis. Iron tends to track with mileage and we often see declining iron uptake rates on longer OCI's due to established chemistry. Often, but not always. The list of used oil analysis in #2 (the FJ Cruiser) had a considerable number of long intervals.