Thanks for the replies. We are going to leave them in for wheat, and take them out for soybeans, not sure about corn. This is our 3rd season with the machine. We think the filler bars caused us some problems during soybeans. I may have the proper part names incorrect, so please bear with me. During the last two seasons in beans, we pushed out some tin on the frame that holds the concave and lower rattle chain. It happened on both sides; one side the first year and the other side last year. We ended up replacing the whole frame this summer. In talking with a Gleaner mechanic, he felt that with those bars in for beans that a green slug went through and pushed out the sides. Without the bars, the slug would have just went through the concave. I hope that all made sense, I'm just the message relayer. One more question, did the L and L2 have any difference in concaves? Apparently the one in ours has been replaced with one out of an L.