I suspect you have an issue with the vehicle speed sensor. The TCM and PCM use this sensor to determine vehicle speed for use of the speedometer and shift points.
I suspect you have some codes so let's start with checking codes. If you can't pull them then most parts stores can do it for free. Let me know what they are and we can go from there. If there are no codes then we will need a scan tool to monitor the vehicle speed sensor to see what it is reading.
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Monday, December 9th, 2019 AT 7:13 PM