J72, Your count with the spreader off still sounds high. In a 18" discharge width by 16" front to rear would give you 2 sq. ft..Takes around 70 soybeans in this 2 sq. ft. to make a bushel. Try and take a count across the width of cut(30ft.) after the combine has passed.Then also take a count right behind header across width of cut. Subtract the header loss from total loss and see what you end up with. It takes 4 soybeans per square foot to equal 1 bu.. We try to shoot for 1% or less of total yield.(ie;40bu._acre times 1% equals .4 bu. total loss) Sometimes with adverse conditions such that you describe with all the green material going through,this is not achievable. The cylinder bar mounted to grate can cause rumbling especially in tough to convey material.Also,keep in mind that the tooth hieght is also a factor. I like to mount F2 toothed concave bars directly to wires on sep. grate. If bar is mounted on top of crossbars and not to wires,this can really slow the flow down. I have taken bars and cut them down to fit in between crossbars so only the teeth extend up above cross bar. Remember though,you are working with an adverse condition,so a light rumble that is short and quick would be common in my mind. If you have a continual growl,you have lost consistant flow through cylinder and you may have to add two or four cylinder bars to get the flow back. This may also require another bar on sep. grate. The sep. lugs have excellent results so far but in hard to convey material they don't have the capabilities to keep material flowing. My opinion only,if other have thoughts or comments please feel free to voice them. Hyper Harvest II P.S. Working with a low-profile cylinder bars for seperator end that have alternating height on teeth.(ie;____''''''''____,''''''____'''''')So far,positive results.Will try to get pic to Tom l.