The issue here is airflow. The factory bags will handle grass no problem, but the more you use them, the more the holes in the bag weaving get clogged. It's not noticeable when bagging grass usually, but can make bagging leaves a challenge because the leaves are so light. So, Deere has 'loose weave' bags to help with this issue. Essentially, with the loose weave bags, the thrust of air that the blades are creating can escape faster, thus increasing your 'suction' power for the leaves. See picture below. Also, make sure that the bagging blades GX25668 were installed when the dealer installed the bagger. I've had situations where they forgot to change the blades. The bagging blades have a higher lift which creates more air flow. Hope this helps!
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