Hello. Audi a6 c4 1995m. 2.5tdi 103kw 6speed manual. Im geting whining noise from it. Its started 80t km ago and now it start's ant lower speed's. Its start's about at 30km/h ant faster you go the louder it is. Could it be a differiantial? Becouse its whining even when im in neutral gear. Sorry for my bad english. There is a video.