I have a 328ti, have been told its running mostly 318ti rear end, with a 3.29 small case diff. Sounds as if diff is going, and was looking towards options on what to go to, car is planning on being a street legal track car. Also has a vibration under heavy acceleration and damging center bearings, believed all linked so would look at replacing all gear. So what diff/driveshaft etc should I run that would fit my car? Any help greatly appreciated. Cheers