I want to thank all of you for your useful input......... I will stick to my old ways, install new filter and new Mercon V, the fluid Ford recommends.... Thank you for confirming my thoughts on the trans back-flush.
I am not having any problems, just my normal transmission maintenance. I do have a programmer installed, and I raised the firmness of the shifts. It has lowered operating temperatures and increased my miles per gallon.
Thanks again, Ron