Thanks for all the good advice.
The computer for the transmission was replaced recently. The speedometer wasn't working before that, worked for a short period after the new computer was installed then stopped working along with back up camera and back up beeper. Had the Allison guys check it out, narrowed the back up camera and beeper down to a relay. I replaced the relay, camera and beeper started working but no speedometer.
I know my gps will give me speed but would also like to keep track of miles...