I change the belt and the tensioner part no 11 28 2 339 154, I buy it from Ebay and it com from Poland the belt was "Continental" and the tensioner was made be ball bearing manufacturer "INA" It was a complete set of all wheels,belts and the tension springhttp://www.ebay.co.uk/itm/BMW-3-E46-5-E39-330D-530D-3-0D-X5-3-0-D-ALTERNATOR-A-C-BELT-TENSIONER-FULL-SET-/222074143773?hash=item33b4a6841d:g:GVMAAOSw9KpXAWt 1