Yesterday, I bought a used JD 606 6' rotary cutter from an old man who has just had it sitting for fifteen years. It's mechanically sound, well greased, and everything works smooth. However, it sure as heck seems to turn slow. The clutch is good and with the tractor humming you can watch the blade go around and pretty much count the swings. It's almost like it is geared crazy low, but it has the factory decal on it from JD that says it's for a 540 PTO. I know it's not the tractor, it spins my finish mower just fine.