Replacing factory GM oil/Tranny coolers with external units

[4xcrazy]

I'm not arguing about using the factory cooler, it's added cooling, but this argument about the factory cooler warming up the fluid gets me. Has anyone ever touched a trans cooler line from a cold start? Those lines get good and warm way before the engine coolant even starts to get warm.

 

[Stein]

I'm not arguing about using the factory cooler, it's added cooling, but this argument about the factory cooler warming up the fluid gets me. Has anyone ever touched a trans cooler line from a cold start? Those lines get good and warm way before the engine coolant even starts to get warm.

I don't know. I've watched my factory water, oil and trans temp gauges on my new Dodge for fun and water is at temp in less than a mile, oil takes 10 miles or so and trans temp trails oil by quite a bit (about 20 miles before it hits peak and stabilizes).