I have a 2009 C50, had it for about 2 years now with not one issue. Took her for a ride today and had a popping, clanking noise upon firm acceleration, sounded like it was coming from the shaft or the rear end. Then when riding it home it got waaaay worse. Basically sounds like the rear end is grinding bad, limped her home idling in 2nd gear....oil level and color looked good to me......and ideas?? Direction??? known issues??? Any information would be awesome....