I have digital guages and the tranee temp is spliced to the ECM wire for pan temp. Non towing I can get to 200 and towing 215 degrees. I have a temp meter and have shot the input and output lines at the cooler. When my guage says 205 the imput is 180 and output 160-165. It seems like the guage is reading way off since the cooler imput is way lower. Tranee fluid is fine and the light has never come on. I have checked this several times when I stop and the meter shows way cooler than the guage.
tks
Rock

 

Just got home from work 12 mile dr. Digital gauge says 185. Line into cooler 150. Return line 135 and pan 165 when shot with heat gun. So much for gauge. Anyone know at what temp the dash light comes on?

 

Trans Over-Temp Lamp-On Message - Each
time the cluster receives a trans over-temp lamp-on
message from the PCM indicating that the transmission
fluid temperature is 135° C (275° F) or higher,
the indicator will be illuminated and a single chime
tone is sounded.