727 Transmission rebuild… help!

Hi, I’m new here so please excuse me if I’m posting this where I shouldn’t be.

A couple times now I’ve torn apart the stock 727 that we swapped into my Duster, new clutch packs O rings etc.

I’m having a problem when we bench test the front clutch, the air just hisses right through without applying the clutches at all. I replaced the piston seals, but that made no difference, and I know for a fact the seals are put in correctly.

What’s going on? Any help would be appreciated, thanks!

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