Note: Servicing of the mufflers, resonator or pipe requires the replacement of the exhaust system as a complete assembly.

1. Remove the oxygen sensor wiring harness heat shield. Refer to Oxygen Sensor Wiring Harness Heat Shield Replacement.
2. Remove the connector position assurance (CPA) retainer.
3. Disconnect the heated oxygen sensor (HO2S) electrical connector.



4. Remove the HO2S.



5. Remove the muffler to exhaust manifold pipe nuts.
6. Suitably support the exhaust system.



7. Remove the exhaust hanger to the rear suspension support bracket bolts.



8. Remove the rear exhaust hanger bracket to the rear compartment side rail bolts (1).
9. With the aid of an assistant, lower and remove the exhaust system.
10. Remove and discard the muffler to exhaust manifold pipe gasket.



11. Remove the rear exhaust hanger to hanger bracket nuts.
12. Remove the rear exhaust hanger brackets.

1. Install the rear exhaust hanger brackets.

Caution: Refer to Fastener Caution in the Preface section.

2. Install the rear exhaust hanger to hanger bracket nuts and tighten to 30 N·m (22 lb ft).



3. Install a NEW muffler to exhaust manifold pipe gasket onto the studs.
4. With the aid of an assistant, raise the exhaust system.
5. Install the muffler to rear exhaust manifold pipe.
6. Install and snug the muffler to rear exhaust manifold pipe nuts.



7. Install the rear exhaust hanger bracket to the rear compartment side rail bolts (1) and tighten to 50 N·m (37 lb ft).



8. Install the exhaust hanger to the rear suspension support bracket bolts and tighten to 30 N·m (22 lb ft).
9. Tighten the muffler to rear exhaust manifold pipe nuts previously installed to 25 N·m (18 lb ft)



10. If reusing the old HO2S, coat the threads with anti-sieze compound, GM P/N 12377953 or equivalent.
11. Install the HO2S and tighten to 41 N·m (30 lb ft)..



12. Connect the HO2S electrical connector.
13. Install the CPA retainer.
14. Install the oxygen sensor wiring harness heat shield. Refer to Oxygen Sensor Wiring Harness Heat Shield Replacement.



15. Connect the HO2S electrical connector.
16. Install the CPA retainer.
17. Install the oxygen sensor wiring harness heat shield. Refer to Oxygen Sensor Wiring Harness Heat Shield Replacement.