...Just my thoughts here...
...From what I get from the different charts, they reflect mainly on the fluid itself, and it's temperature...
...The fluid starts failing as the temps get above 180 degrees and from my research for my guage install, I found that is a common A4ld temp reading out here in the summer..
....From what I've seen, 190-195 is a max. peak temperature for the fluid....At above this temperature, the fluid degrades...So, say it hits 210 degrees...If you do not immediately change the fluid, and continue to run the same fluid for extended periods, your tranny life expectancy will greatly diminish...
...I will be adding more bling to my tranny in the future to help protect the large investment cost that it took to have it rebuilt...In fact, My X is the first truck I have ever put synthetics into...It will be the first truck I've owned to get a synthetic transfusion of tranny fluid..
...I do know that the different tranny's do have different operating temperatures however, and again, these are just my thoughts on the charts...