There is no real relationship between engine coolant temperature and transmission oil temperature.The engine temp. will be at operating level in less than a mile while the trans.will be barely warm at that point especially in cold weather.Since the torque-converter is the main source of heat,stop and go traffic will get the oil temp. up best.My Allison shows the most heat under these conditions.
04 Southwind 37C W22
DIY Rear Panhard Rod