Hi guys I'm new to the forum, we just recently purchased a 21? ft Alloway Stalk shredder and we are running in on a John Deere 8230 MFWD. It runs the big 1000pto shaft. The problem we are having is the chopper shakes the tractor really hard when running the chopper over 1400rpm. If I run the tractor at 1350rpm (680 pto rpm) the chopper does just fine, no shaking, and it chops nicely at 6mph. But when we shut the chopper off the whole thing shudders and shakes as it is slowing down. Has anyone experienced this? Are we doing something wrong? The blades aren't terrible, but there are a few worn ones, bearings look good, could one missing blade that we haven't seen make it shake this bad? Thanks guys!