Since it is the season to test the antifreeze in your equipment and vehicles, this may be the time to talk about this?
Hopefully, there are some chemists, or people who know, that will chime in here.
All manufacturers say you should clean, flush and refill your cooling system about every five years.
Why? What goes bad in antifreeze? Can the pH and nitrates be adjusted with the addition of new additives?
Explain green, orange and red antifreeze as well as oat and hoat coolant.
I see Ford diesels recommend an SCA, (Supplemental Coolant Additives) be added if needed after