Make sure at wot the tv is pulling the valve open all the way when you have the pan off. Probably need a helper to see or push the pedal down.

I had a guy on tb.com post he used this so I bought a pail full and put it in. So far so good. Why you ask? It was cheaper than trans fluid. I did say I am on a budget. It doesn't smell burned and hasn't gotten discolored yet.
If you have the budget n micale pushes dex vi. If my budget wa unlimited I'd give it a whirl but I'm pretty happy with the coastal stuff so far.
Probably need to ask your builder what he thinks, especially if there is a warranty.