Old thread - sorry, but I want to add some observations, now that I too am a member of the Xfire SC Grenadiers club. With both pieces of the aluminum pulley now removed,(it split) I inspected the shaft to which the pulley attaches closely and found numbers that had been hand scratched into the shaft, for what reason, I have no idea. As the shaft turns, a dry sound is heard from the rear of the SC. So I put on my stethoscope to confirm and yes, the noise is from one or both of the rear bearings of the SC screw shafts and I feel like it is best at this point not to continue the failed dogbone /pulley replacement until I can feel secure about the SC and its future longevity. I feel that this SC needs to come off and be rebuilt or restored before putting it back in service. Is it possible that a vibration was set up by the failed screw bearings which led to the failure of the dogbone and subsequently the pulley split? or, would one guess that failed casting of the aluminum pulley caused the pulley to first split resulting in the dogbone failure? Either way, whats done is done and what now has to be done is change out the SC I feel. I was going to try to get by with changing out the SC oil, but those noisy bearings are sealed type and the SC oil does not lubricate them I see. Is it true that only one place in the US can rebuild these? A link would be helpful and some tips on crating the SC for shipping please....Thanks in advance...Peace