Converter Question?

[art leong]

I pulled my trans today and can see some "blueing" on the stator support shaft. There is also some discoloration inside the neck of the converter. The car had dropped way off in the short times (2 to 3 tenths). And some had thought a broke a sprag in the converter.
I had a stator support shaft spin on me a year ago. And the car left like it was towing a 5th wheel trailer. That time I could spin the support by hand. This time it seems tight. But I wondering if it isn't spinning urder a load.
I going to send the converter back to the manufacturer. And I'll replace the front pump assembly, that houses the stator support shaft.
I would like to know, what if anything went wrong. Not just replace everything and hope I found the problem.