I have done 3 uoa's over 5 years, at one year 5k miles the tbn was over 6 changed oil prior to sending sample, at 2 years 10k miles the tbn was over 3, and I didn't bother to get tbn on third or anymore uoa's as I have set my oci. I decided with a 7500 1.5 year oci to be extra safe, the truck doesn't get used that much. The wear numbers are junk, it is a ticking hemi. or should I say was a ticking hemi, redline killed hemi tick.
The wear numbers have steadily went down, especially the copper even though a 2 year interval and the last uoa I didn't touch the crankcase, the previous uoa I changed the filter 1/2 way through and cut it open. I use RP filters and also cut it open after the 2 year oci, was still like new. So the previous uoa got a top off qrt, and the last uoa still beat it by about 30% in wear numbers. Not fair to judge redline or any oil in a hemi. There is some thought esters pull out ions and that adds to wear numbers, I don't really care about that, what I care about is not having hemi tick, and redline was the cure for me. Assuming the clone oils or if redline is the clone, all the formulas would produce similar results. We have done a lot of uoa's over there as well, there was one oil that stood out as having the lowest wear numbers and that was PUP. I do think there is a difference between wear numbers and what is best to protect sliding metal pieces, but your opinion may differ.
All documented on Ramforum, Burla over there as well.
Mind blowing oil filter thread below, if you want a long oil change interval, you would have to be daft to not use a spun microglass filter. Royal Purple filtered best in this test, and that is what I'n gonna use forever, as I bought enough of them to last 20 years.
oil filter test
Here is the test, they put a patch behind the media of every oil filter, so what gets through shows how well or not well the media is filtering. I believe they heated it up to operating and put it under pressure, just like how an engine operates. This was the patch they put behind the RP filter. at 30 microns, nearly nothing gets through. Spunmicroglass flows better, filters more, and even after two years filters like new. You need to match that long oci you seek with the right filtration. Fram Ultra is golden as well, with price as a consideration Ultra was the winner of the test.
versus a paper filter like motorcraft.