That test port is where the temp probe belongs. It will give you about the same temperature as oil in the oil pan. It is from the oil pan that the tranny draws its oil supply. That is the temperature the tranny will live-or-die by. After the oil goes through the torque converter and the rest of the transmission, it naturally heats up, but once it goes through the coolers, much of the heat is dissipated and the oil is cool enough for reuse from the oil pan, unless there is an overheating problem which the oil pan temperature will show. Monitoring that temperature is what counts the most IMHO.
