Hi guys,ive just brought an audi 2.0 tdi sline estate 2005 with blb code engine,its done 174,000 miles with full audi history and belt done in 2012,got it pretty cheap,i went to view it and there was a knocking that seemed to be coming from the engine,thought it might be a pulley or something,didnt think it was anything serious but not knowing the history of these cars i brought it i had my mechanic check it over for him to say its the balance shaft..bloody great not cheap to replace,i found a second hand balance shaft and oil pump for a bre engine..gear driven one..can i replace this with mine..it has all running gear etc i was told it will fit blb engines?..just wanted more advice here please if anyone can help would be great..