I finished the AutoEx treatment on the older Taurus (200k miles), which has had pretty regular tranny fluid changes but no cleaning, and Lubegard Red for the last three or so fluid changes. I started noticing a 'chatter' during acceleration while cleaning, which I guess is 'toque converter clutch chatter', and it evntually started doing it all the time while accelerating. I put new Chevron Mercon in after 1000 miles of AutoRx, doing the 'full flush' myself, and there was better shifting, very little shudder but more in the gears that weren't used as much during cleaning, but there was still a bit of chatter. I put a bottle of Lubegard Red in and all is well now, even less shudder and no chatter.
If you have an auto tranny I recommend cleaning with AutoRx.