Speed Sensor question

Transmission is stuck in 1st gear, no slipping of any kind. I have a 1995 3500 dually.

Where is the speed sensor located ?

Javadape

On the left side of transmission.

ok, i changed the speed sensor on the side of the tranny and initially NOTHING changed. So I figured it was the tranny bc it was still not shifting correctly.So i drive it 13 miles home with it acting up the entire way, with plans of taking it to a tranny specialist the next day...the next day i take it and it works fine and the tranny guys put it on their tranny computer and it codes 81 and 82 (shift solanude a abd b)

they say theirs niothing wrong with it and it works fine......

i figure the computer reset inself and it was the speed solnode after all

Javadape