After 2 yrs ownership I just now noticed this. 5.0 2016 4x4 6speed xlt.

Trailering on interstate, 87F 73mph, trans temp might be 206F. Then drop to 197 when AC is on a few min.

Something to do with shutters opening and both fans coming on I suspect.

 

Also when the AC is on all the piping gets cold which is near the transmission!

 

It’s because when the ac is on the fans are commanded on.

 

A third option are the shutters, but I'd bundle it with the fans (2nd option). If shutters are closed, turning fans on at high speed could lower the temperature, but the behavior would be the same that if the shutters are open: both would lower the coolant AND transmission temperatures, since the transmission cooler is heated/cooled by the coolant radiator. To find out, we need the digital coolant temperature display activated with FORScan. If the transmission temperature goes down, and coolant temperature goes down as well, we know it's due to the fans and/or shutters. If only transmission temperature drops, then the 1st quote should be the reason why; what else could it be? Only one way to find out. He he. So post results folks .

 

The lines are not cold at the condenser. Option 1 is not a valid hypothesis.

 

Antifreeze running through the Transmission Heat Exchanger,Cooler Antifreeze the more cooling at Transmission with the Shutters Open and the Fans on.

 

Remember the days of turning off the AC and opening the windows to keep it cool? Then when it got really bad you would turn on the heater full blast. It could be a horrible ride trying to keep it from overheating on a really hot day.

Guys who say they don't build them like they used to are correct, just backward.

 

been there done that

 

Wow thats cool