Can you do me a favor and check to see whether the top part of your deck's discharge opening, facing out, (from front to back) is flat? As strange as it seems, the opening on my 52" Turbofoce deck on my Z-453 is not -- it bends towards the mower about 1/8 - 1/4" from front to back. I used the edge of a 36" bubble level against the metal, and mine definitely is not smooth. BTW, there was nothing stuck to the opening causing this. This is a brand new mower with 40 hours and definitely no abuse (other than what my wife gave me when I bought it ). The reason I ask is that I just got a Quikchute (nice product BTW), and I noticed a good deal of grass coming straight up and out towards the back of the discharge opening when the door is fully closed. I thought the Quikchute was out of adjustment, but its not -- the Quikchute door is perfectly flat, but the deck opening isn't, and that's causing the door not to be flush with the opening when its closed. I would think that the opening should be flat. Hope this makes sense -- appreciate it if you could check and let me know. thanks a bunch.