If you have a automatic transmission problem that would prompt you to use an additive to fix, the symptom may go away for awhile if you use it, but the problem will still be there. And inevitably, it will come back.
A mechanical failure of the lockup clutch in a converter will likely not be cured by any amount of additives.
These are just my humble opinions, but if it were me, I'd be looking for a new converter because the longer you let this go, the more damage is being done to the clutches in the tranny.
