I had a lot of vibration the shaft at about 120 hours. I took it into my dealer. The PTO wasn't tight. The one next to the gear box. He replaced it and it's been smooth till the other day. I took the cover off to check it and its loose again. It lasted about 45 hours this time. The dealer said he had never seen one get loose before. I've greased the joint ever 8 hrs. I guess it's going to be OK? But, it vibrates the deck. Not a lot but you can feel it while your mowing. Anybody else have a problem.