What's wrong with it? If it died again in just a few months there is likely some common denominator to be looking for.

 

I'm having doubts it was the transmission itself causing the problem, considering you replaced it with a Performabuilt transmission and FTI converter only to have it die a few months later. Nobody's perfect, but you went with top of the line equipment and builders.

There's gotta be some underlying problem with your vehicle (that probably would've killed a 4l80e too).