I have a '94 Ford ranger that currently has shifting problems. it runs fine in reverse but will not shift out of first. It is an automatic transmission 2.3L and I have had a variety of answers on what is wrong. Could this be a bad transmission or something else?

Ranger Automatic transmission
2.3 L
It has almost 120K miles.

I am starting to dread my Fords currently I have a 2001 Focus with a piston on the motor. I opened the hood and there it was so I am looking at a heafty price to fix it along with a 98 tarus that needs the front end worked on. so I am hoping the Ranger might have an easy fix instead of the tranny but any input would be appreciated.