How hot is your transmission running?? I'm assuming your engine runs around 210, if my transmission spends any time in that range then I'm very concerned, considering it normally peaks around 165 after adding the cooler. Maybe your setup breeds higher trans temps?
I have 32rh with cooler and mopar deep pan(sensor in pan),456 ratio and driving for a few hours in 102 degree heat at 60 mph my auto meter gauge maybe got a little past 195.