Originally Posted by kanuck15
^^^ what he said. My trans shop that built the trans for my diesel bypassed the radiator cooler and just ran a heavy duty plate cooler in front. For the reason of heating it up. A proper trans should never see temps over 160 unless its towing real heavy or you are flogging the ever living crap outta it. Even then 180 is a redline for mine.
Good idea to run it separate from the radiator. I had my Explorer plow truck's radiator go out, the trans mixed with the coolant, not a fun repair job.
Also another reason I hate autos....