I'll get straight to the point. Do i have an LSD. I have a 06/97 2.8 roadster that has done just over 100k and needs the diff oil changing because it whines like a *****. Ive had a look over the net and it seems a contested area, some places state that all 6cyl had an LSD while other say it was an option. Ive had a look over the diff casing and cant find the "S" thats suppost to be stamped on it but its quite rusted so i cant rule it out. I had BMW print me off a build sheet and that doesnt show an LSD fitted so at this point im thinking i dont have one. If anyone can shed any light on it it would be much appreciated. Im also toying witht he idea of putting in LSD oil anyway because it still has the same base weight as the open diff oil.