More than likely this is a reverse servo issue assuming the shifter is adjusted properly.
If the shifter is out of adjustment it may not be easy to find reverse. I included the process to adjust this as well as the servo.
The servo is what applies band to apply reverse and when it fails, it is not able to engage reverse and will act like it is in neutral.
Let us know if you have questions with this.
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Wednesday, May 12th, 2021 AT 5:30 PM