GOT CODE 74, TRANNY CALCULATED OIL TEMP IN USE.WHAT SHOULD I FIX?

Question

SYMPTOMS-HIWAY SPEED, LOW RPM, RANDOMLY CLUNKS HARD,
AND WHENEVER GOING UPHILL. HOWEVER I CAN DRIVE FOR HOURS IN THIRD GEAR AND CRUISE SET AT 57.

Answer 1

Code 74 Calculated oil temperature in use

Code 12 battery was disconnected

When you get a calculated temperature in use , the transmission will operated in wrong shift schedule, What can cause this is the transmission temperature  sensor signal or the transmission range sensor ,If you want to attempt a repair the temperature temperature sensor is part of the transmission range sensor.you will need to remove the transmission pan to access the range sensor,