I did the first serious drive since the new stat went in. After thirty minutes, trans was at 165, before it would be 180-190. After a full hour it was 180. In about 200 miles today, it never went over 192. That was after repeated blasts to get around truckers hanging in the left lane on hills. Temps would back off some when returning to a steady cruise.
Before the new stat and flush, it was 203-205 on a regular basis when not towing. I’d see 212-215 with the rv.
I’m starting the think my stat didn’t fully open since new. The only time I saw anything erratic was about 4-6 weeks ago it had a wonky warm up when the gauge went back and forth a bunch to start the day, like it would stick open and closed and the trans hit 210-212 with no trailer on a cold day, upper 20s-30s.