It would not switch gears when going 65

Welcome to 2CarPros.

Do you mean that once at 65 it will not downshift? Do you mean it won't shift to overdrive? If you making it to that speed, it has to be shifting, so I am trying to narrow down what is happening.

There are several things that can cause shifting issues. Without a diagnostic trouble code from the transmission control module, it becomes a guessing game. For example, the overdrive overdrive solenoid may have failed or the torque converter clutch. These components are located on the transmission valve body which requires the pan to be removed. I don't want to suggest things and be wrong only to cost you unnecessarily. However, I will try to provide possibilities based on your answers.

Let me know,
Take care,
Joe

Welcome back:

No problem with the delay. I did see it. Is it downshifting or slipping? If it is downshifting which is what you originally said, the first thing I would do is have the TCM re-flashed to see if that remedies the issue. Since there is no trouble code and it is acting like that, the problem may be the programming. Also, since it does this at shift points, it could even be a transmission line pressure issue, but at this point, I'm leaning toward the TCM (transmission control module).

Was the mechanic certified on this type of vehicle? Was he able to do more than just check for codes?

Let me know.

Joe