..Transmission should run 170 - 190 degrees.The tube in the lower tank where the coolant temp is about 150 - 160 ( Delta T)warms your trans fluid for colder temperatures.
i run a typical 340 with a Dynamic 9 1/2" converter plumbed only to a small external cooler.I don't baby it and i have never seen my trans fluid it above 160 degrees.
..unless towing or racing I'm wondering if no external cooler would be best?
