Causes and Fixes P0730 Code: Incorrect Gear Ratio 

How to fix P0730 Code: Incorrect Gear Ratio
A P0730 is set when the computer (TCM/PCM) sees a greater RPM difference between the rotational speed of the input RPM and the transmission output of the RPM sensor.
Causes include transmission mechanical failure, faulty shift solenoids, contaminated fluid, clogged filter, and bad valve body.
Possible Causes of a P0730 Code:
Low or Dirty Fluid
Clogged Filter
Transmission Failure (Pump, Planetary Gear, Solenoid)
Bad Computer (TCM/PCM)
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