4500 Stall Won't Stay Locked! Help!

[dtsngit]

I've got a 4500 Stall in my 4L60E. I've set the converter to lock at 50MPH on the highway in 4th gear and the car does. But usually not long after it will unlock. Then later down the road it will lock again for a little while before it unlocks again. After it unlocks I can tap the brake and it will lock up again shortly after. I think it has something to do with misfires from the stall. I have turned the misfire detection off but it still doesn't help. Anyone had this problem before?

[flame]

If you have the misfire detection adjusted then monitor the brake switch status and see if that is causing it.