I have an 07 F150 4x4, have an Edge programmer. I see a strange thing happen to my trans fluid temp. If it is above 150 degrees, I can be driving and it will be stable, let's say 160. When I pull up to a light, it will fall 10 degrees, in 15 seconds. Then, as soon as I pull away, it returns to the temp it was while I was driving. ?? Any ideas? Also, this only started happening after I installed a trans cooler.

 

Its just cooling faster with the added cooler, no big deal.

 

I wonder that too, my scangauge (only had it a week or so) I have see similar things. It might be referesh rate and coasting? I am not sure, made me suspicious and about the accuracy.

 

there is no way it cools down 10 degrees in 15 seconds, and then turns around and climbs 10 degrees in 10 seconds.

 

I agree. does not seem possible. unless you have Liquid nitrogen cooling.

 

Where is tranny sensor located? Because I have a deep tranny pan and my temps have gotten up to 195 in 105 degree weatherin stop and go traffic. I flush my tranny every 30k miles and replace the filter.

 

Maybe its plausible that at a stop, it generates less heat and the cooler can drop the temps. As soon as he moves, the transmission generates more heat. And maybe you installed the trans cooler right before the temperature gauge.

 

In 85°f heat mine drops 40°f in 4 hours of time while working. oil does not cool off that quickly.

 

i can take a vid to prove it will drop that fast, i have a second cooler and mine does the same.

 

I didnt know your transmission used oil

What I was saying is that the extra transmission cooler couldve been placed before the thermostat. A stopped truck generates LESS heat because the transmission isnt trying to push the truck as much as under throttle. With those two factors, I believe that it is possible that the temps fluctuate that fast.