After the latest transmission failure, I decided it was time to break down and actually rebuild one completely. I've rebuilt a few TH400's and TH350's in the past, AW4 isn't too bad, but definitly more complicated. Found a few things in this one. The "rebuilt" pump I bought seems to have lost a chunk off the section where the impeller rides. This may have been the cause of this failure - I found little grains of cast in the section of the tranny that had the burnt up clutches.
Taken apart
Pump with chunk missing from casting
A lot of the clutches were burnt up
Mostly back together
Todays task - valve body rebuild