Bob Wilson:Here's your copper content Bob:

Hi Bob,
Stumbled upon this other day. I think this is where your copper in your Amsoil ATF UOA came from. You were right about the additives but this should make you feel better that its not attacking motor field wire. Or maybe it won't make you feel better as it seems it has attacked your bearings/syncro's. I don't believe Redline uses much additives as it starts off with highest quality Ester base stock available. Additives are used to improve poorer base stock I believe.

Transmission Oil Specifications (2) - International Mazda Forums

 

Yeah Bob & I had quite a lengthy dissertation a while back concerning this very subject. He changed out his Gen 1 ATF with Amsoil ATF. Pulled a UOA and discovered high copper content.He was concerned that it was possibly conductive material from the motor windings. My position was the same as yours. If any motor winding was exposed to the fluid bad things would happen. The whole discussion is whether the WS fluid has some dielectric property to it to prevent this. My position is the WS fluid could be 100% dielectric and you'd still have a big problem with a compromised winding.
I changed out my 07 ATF to Redline D6 which got alot of hey you can't use that it has no dielectric properties posters.Now the only question I have is based on this latest link is Redline oil pure enough that it has no EP additives (extreme pressure) which seem to attack copper. I sent Redline Corp an email asking about this and I will also pull a 2K sample on my Redline soon.