8 speed getting warm after 30-45 min on highway

[14ramcorey]

Anyone else gettin a big increase in tranny temp when your on the highway ...mines stay around 190-195 in town when I hit the highway it climbs and has seen over 225 than it starts down shifting hard and whining after 205 degrees

 

[14ramcorey]

Mines a 2014 5.7 hemi 8 speed 79,395 miles 2 Nd trans in and multiple updates

 

[crash68]

I'm going to guess when your transmission was replaced that the thermal management unit was not replaced.
It's the thermal bypass valve that is the usual culprit that causes the high temps, unfortunately it's part of the TMU.