What about it? It's impossible to provide and answer if you don't ask a complete question.
It might be the transmission range selector
There is only the speed sensor and the range switch.
The only "sensors" on the transmission are the speed sensor at the top in back, and the range switch on the front.
It's part of the range switch on the transmission.
Front of the transmission, the thing the shift cable attaches to.
You replace.
It is possible if the selector doesn't lock in to position. Also check the transmission fluid level. Low fluid will also be a factor. There could also be other issues that should be looked at by a professional, reliable transmission shop.
Not sure what you mean by transmission selector sensor. The transmission range sensor reads what position you have selected with the gear shift lever.
Front of the transmission.
On the transmission selector you put your shifter in neutral position and then you can move the transfer case selector to high or low.
range sensor is located inside transmission. remove pan and it is attached to shift selector rod and vave body.
It's known as a "Super 10"