Transmission not shifting to 3 rd

The TV cable is for the passing gear. Your transmission probably is just worn out. Should go to a transmission shop for proper diagnosis.

Up early there TrannyMan, good morning.

No hard feelings there TM, If you watch when someone is involved with a post, question, look at the time there on that post, read what there saying, give the respect to this guy who is working with that persons. There is a method to my diagnosis in order for me to eliminate possible conditions to a problem. I will harp on people until I am satisfied that a situation has ben thoroughly checked. People like to leave out things that matter when diagnosing, and we are on the other side of their computer screen. Read what was said and contribute when you see when that persons is missing something, and can use the help. Like for example...Rowefast, couldn't it be.....? It is all about respect to the other persons answering the question. There are some very smart people on here, and then there are others who try, but still need the respect. Then there are the other pain in the a**, shirt tail riders, just looking for points, you know what I mean?

Bought a 1989 GMC Sierra SLE when it warms up it will not shift gears