Let me get this correct, you added 5.75 quarts of ATF after a complete drain? If that is the case, I strongly suggest you recheck the fluid level.
Cold, a full tranny should read about 10mm below the min mark, best to check at operating temp though. Seeing as how you only have 5.75 quarts in there I'd say you are save to gauge it by the cold check. This tranny should take nearly 8 quarts to refill after a thourough drain. I normally add 6 quarts, then start the engine and let the tranny pump for a few minutes, clycle through the gears and check the level, top up slowly until at the full mark at operating temp.
Hopefully you haven't driven too far on a low tranny.
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