I wouldn't worry at all with 180F tranny fluid temps SAE recommends having at LEAST 160 F trans fluid temps to keep the additives in the fluids at the proper operating temps Petroluem based tranny fluids will start to turn the dye in the fluids from red to brown around 280 to 300 F and then turn to black at or above 325F temps My old Ram 2500 CTD with the trailer towing package never got the fluids above 130 F Summer or Winter in the Mojave desert in SO CA Unless I was towing my enclosed race trailer with the car in it The most Temps. I ever saw on that gauge was 230 F going up the 18 mile long Baker grade on I15 during the middle of the day in August with the outside air temps at 117 F I would change the tranny fluids on every engine oil and filter change(3500 miles usually) to get rid of the condensation in the tranny fluid