Euro 6 compliant catalytic converter for the BMW 5 Series G30 with B48 four-cylinder engine. Features a high-cell-density ceramic substrate with precious metal washcoat for efficient conversion of CO, HC and NOx emissions. Stainless steel housing with OEM-spec flanges.

1. 1
2. Heat system with 15 minute drive
3. 2
4. Allow to cool slightly — not fully cold
5. 3
6. Spray all bolts with penetrating oil
7. 4
8. Remove O2 sensors (18mm or 22mm lambda socket)
9. 5
10. Remove heat shields
11. 6
12. Unbolt front flange from manifold (3 nuts)
13. 7
14. Unbolt rear flange
15. 8
16. Remove old cat
17. 9
18. Install new cat with new gaskets
19. 10
20. Reinstall O2 sensors (anti-seize on threads)
21. 11
22. Torque all to spec: flanges 25Nm, O2 sensors 50Nm.