If you are noticed any extra vibration in your machine this year as you finished, you are going to want to check this out this winter. We pulled the feeder house after to wheat to do some work and found the spacer in the the right hand spider had broke at the weld. This is the one next to the side of the machine. This let the cylinder flex which then broke the drive spider next to it. It also broke the concave. We thought at first it was just age. This machine is a 1990. However, the area dealer ended up with atleast four more machines in thier shop with the identical problem by the time soybean harvest was half thru. I haven't had time to pin down the exact age of the other machines, but understand a couple were newer than ours. If you do the repairs yourself, which we did, it is easier to disassemble the cylinder in the machine than to try to remove it the the tech manual describes. Make sure that you number the bars in order. Use the keyway in the shaft for a starting point. We replaced both drive hubs because of the flexing. Wanted to make sure we didn't but it back together to have the other one break. Reassembled the spiders and all the bars to make sure everything was square and then tighted it all. Tighten Hubs to the shaft last so you can make sure that it is centered and there is no side force on the drive hubs. Before we reinstalled the gearbox on the drive shaft, marked one bar and spin the cylinder several times to reinstall the balance washers. This takes time, but you need to try to balance the cylinder as best you can. Put filler plates back in after you have done this. Would like to know how many others have had this problem.