Hi and thanks for using 2CarPros.
The vehicle has a transmission control module (TCM). Something may have shorted there or in one of the speed sensors. However, it becomes nothing more than an educated guess without checking to see if there are diagnostic trouble codes stored in the system. With that in mind, you really need to scan the computer. Unfortunately, most basic scanners will only communicate with engine codes and can't read transmission codes.
Here is what I suggest: Unless you have a higher end scanner that can read transmission codes, you need to have it checked for codes by a shop that does. If you can do that, we may know exactly where the problem is coming from.
If you can, have that done and let me know what codes are found.
Saturday, March 16th, 2019 AT 4:26 PM