transmission cooler/temp question

[fordmanSLO]

I had a thought today, and thought I'd run it by anyone interested.

My transmission runs consistently between 100-150deg, while my engine runs consistently around 195-200deg, especially in summer. If I am running colder transmission fluid through my transmission 'cooler' tank on the radiator, just what in the heck am I cooling? Wouldn't it seem like I am heating the trans fluid by doing this? Could someone show me the error of my thinking before I bypass that cooler and run the external cooler only?

 

[spindlecone]

I had a thought today, and thought I'd run it by anyone interested.

My transmission runs consistently between 100-150deg, while my engine runs consistently around 195-200deg, especially in summer. If I am running colder transmission fluid through my transmission 'cooler' tank on the radiator, just what in the heck am I cooling? Wouldn't it seem like I am heating the trans fluid by doing this? Could someone show me the error of my thinking before I bypass that cooler and run the external cooler only?

Interesting question, surely someone can respond.

 

[Glacier991]

First off.... your point is a valid one. If the trans fluid passing through the radiator cooler is cooler than the antifreeze sourrounding its cooling tubes... well the "cooler" ain't operating as a cooler, but rather more like a heater.... and in fact, in cooler months, that is what they want it to do, help bring the trans fluid up to temp faster.

Now CAN it operate to add heat to an already warm tranny in summer? Sure. But I was once told that the antifreeze temp in the location of the radiator where the trans cooler coil is in already more cooled than the engine temp, and that the difference is not significant between the trans temp and the coolant temp in a properly operating system. How true that is I cannot say. It would be interesting for someone with a trans temp gauge to do a comparison.

But the reasoning you have used is sound and solid. Which is why an external cooler is always best added AFTER the radiator "cooler".