We started with a 403 and been red ever since. Got a 2588 and had trouble I never had before, grinding everything up and low hp. Farm milo, corn ,(100-150bu-14%) little beans. All other AF's were grain rotors, this is AFX grain(short rasp bars-4 seperator bars). Started in milo-grain damage, ok power, went to corn- damage, no power. Did the usual stuff, open concave, slow rotor, pull wires(large wire concaves, keystock grates) nothing seems to help. Concaves were plugged in corn way more then any AF I ever had. Return low(1-2 bars) rotor loss high. Changed all filters 3 times, drained tank, pulled suction tube out of tank-no shavings, still engine would pull down to 1900 if you hit a vine. Last day of harvest service rep finally hooked lap top up(no 600) and called case. They said called for fuel pressure and supplied are close enough so engine is making all its power(?) and sent a software patch to try for next harvest. IMO I think the little rasp bars aren't getting the grain out of the rotor compounding the low power. Gordon says he hears this all the time and his bars will fix it. Case reps say they never heard of him(and the problem)and politely say I don't know how to set a AF yet. Please help