If the speedometer and odometer are both not working, I would blame the speed sensor. If only the speedometer does not work and the odometer does work, the cluster is bad.
did you check the speed sensor on the side of the transmission?
Output speed sensor
Is the TCM working normally and throwing no codes?
If the speed sensor is broken several things can happen. The speedometer will not work and the transmission may not shift correctly.
Does your odometer work? If the speed sensor goes faulty both speedometer and odometer stop working.
It is either the speed sensor or the wiring. Have it checked out.
Your speedometer doesn't work.
Your speedometer won't work.
The speed sensor sends a signal to the speedometer to show the correct speed and it sends a signal to the transmission telling when to shift. If the speed sensor is bad the speedometer will not work and the transmission will not shift correctly.
It is probably the speed sensor. It is located on the transmission and sends an electrical signal to the speedometer.
Vehicle Speed Sensor