So I go to get in my truck today and when i put it in reverse I get a clunk clunk clunk. I drove forward and it feels like theres no power. And takes along time to shift out of 1st which also feels like its grinding a bit. Then tried to reverse again. And nothing.. this is the first time anything like this has happened. No signs leading to this... except a guy came and test drove the truck yesterday. Agreed to buy it. And now this. The bad thing is I think he may have caused this. On the way back he got on it about a quarter mile from my house and the rear end felt like it jerked to me. He parked it in my drive way and wasnt driven till just now when this happened. COuld it be trans? or a rear gear issue? Sun gear was also suggested??