The first thing to check is main line pressure. A pressure test with a transmission pressure gauge is always one of the first things to look at if the pressure is not up to snuff nothing works right. Usually these valve bodies have about 180 -200 PSI at 2000 RPM. Your direct clutch clearance also seems to be a little tight, I believe the instructions from Automatic Trans Design=Hipster say .050 - .070 clearance. Tight clearance on this pack will cause premature darkening of the clutches from dragging in the top of low gear. Depending on how old your brake is may tell the story. There may be a newer design that works much better if you call ATD they would be able to tell you that.
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