superz52

I am pretty mechanically inclined, but I can’t figure out what is going on with the transmission in my 97 F350 powerstroke.
Here the scenario; It seems that the torque converter does not lock up properly. This is a intermitting problem, I have a Banks trans commander unit on it and sometimes it shifts fine and the torque converter locks up fine. Sometimes it seems to shift smoother than normal and when the torque goes to lock up its like it barely tries to lock, and the transmission slips. I can tap the brakes and see the torque converter unlock and then lock again, but the transmission still slips. Also sometimes the torque converter will start to lock up then disengage and try to lock up again and then disengage; it will continue to go back and forth doing this.
The transmission has been doing this for at least a year now. Over the past year it would just happen periodically and then it wouldn’t happen again for a few weeks or a month. Now it is happening every day, at least for the past week.
Has anyone ever had a problem like this???
To me it seems like the torque converter isn’t getting the proper signal/voltage to lock up properly??? Could this be in the Banks trans commander? Banks says the trans commander has nothing to do with the torque converter. The thing that makes me question it is that the transmission shift really smooth when this happens. I say smooth, smooth like factory shifting; it is not slipping between shifts.
The fluid level is correct, and I change the fluid about every 20K. This problem is not related to driving in the rain.
I don’t think the transmission is worn out, because if it shifts properly and the torque converter lock correctly, I have no slipping issues..
Thanks in advance to any help.

Unregistered

nobody seemed to help you.... I have a 96 cougar and normally when that seems to happen on our type of cars its the torque converter lock up solenoid. I'd have that checked out.

jeff2003

I have similar problem in Mercury Mystique. The transmission won't shift to overdrive when it's raining or snowing. The car runs OK in dry weather. It looks to me that is an electrical problem. Either wiring or Speed transmission sensor.