I am installing a thm 350 in place of my manual trans. how important, and what does th tv cable do?
You can run without it, but you won’t be happy. The TV cable is what tells your trans to downshift when you stomp it (i.e. passing). A lot of people call it passing gear, but it’s just a downshift. Also, if you run without it, you will need to plug it’s hole or you will leak trans fluid. My cable was broken when I got the car, but the casing was still there and I could drive it with no problems until I could get one and had time to install it.