I had been trying to figure out why my auto connect deck is so rattly sounding at low speeds and from you guys found that it is considered pretty normal. Anyways, I had completely removed the deck and so I put the PTO lever in the rear only position so I could turn the mower PTO easily and so I reached under there and turned the short auto-connect driveshaft that connects to the PTO. The rear portion of it has a female square hole in it that recieves a square front shaft about 5"-6" inchs. When I rotate that shaft, the female portion goes up and down I bet 1/8". It is like when they machined the square hole in back half of that driveshaft, they didn't get it centered. Have any of you guys checked yours to see if it runs true or goes up and down. It seems like that up and down would cause a vibration that could cause the auto-connect to rattle kinda like a tire out of balance. Does that make sense or is it too small of a diameter to cause a vibration?