I recently purchased a b6100 and was told it needed a throw-out bearing. After bringing it home and unloading, I notice a bad vibration at times, and it was difficult to pull out of gear.So I broke the tractor in half and inspected everything and determined it needed a throw-out bearing and clutch plate. After installing it still has the bad vibration at times. Has any-one had a problem like this before? I am now thinking pilot bushing,pressure plate, or possibly a transmission bearing. Am I on the right track? I would greatly appreciate any advice. Thanks rptp44.