GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Warning: Refer to Exhaust Service Warning in the Preface section.

Warning: Refer to Protective Goggles and Glove Warning in the Preface section.

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


    Object Number: 1665113  Size: SH
  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. Object Number: 1670531  Size: SH
  5. Remove the HO2S.

  6. Object Number: 1670482  Size: SH
  7. Remove the catalytic converter to the rear exhaust manifold pipe nuts.
  8. Suitably support the exhaust system.

  9. Object Number: 1670483  Size: SH
  10. Remove the exhaust hanger to the rear suspension support bracket bolts.

  11. Object Number: 1670485  Size: SH
  12. Remove the rear exhaust hanger to hanger bracket nuts.

  13. Object Number: 1670480  Size: SH
  14. Remove the rear exhaust hanger bracket to the rear compartment side rail bolts.
  15. With the aid of an assistant, lower the exhaust system.
  16. Remove and discard the catalytic converter gasket.

Installation Procedure

Caution: Refer to Exhaust System Inspection Caution in the Preface section.


    Object Number: 1670485  Size: SH
  1. With the aid of an assistant, raise the exhaust system.
  2. Install the rear exhaust hanger to hanger bracket studs.
  3. Caution: Refer to Fastener Caution in the Preface section.

  4. Install the rear exhaust hanger to hanger bracket nuts.
  5. Tighten
    Tighten the nuts to 30 N·m (22 lb ft).


    Object Number: 1670482  Size: SH
  6. Install a NEW catalytic converter gasket onto the studs.
  7. Install the catalytic converter to the rear exhaust manifold pipe.
  8. Install and snug the catalytic converter to the rear exhaust manifold pipe nuts.

  9. Object Number: 1670480  Size: SH
  10. Install the rear exhaust hanger bracket to the rear compartment side rail bolts.
  11. Tighten
    Tighten the bolts to 50 N·m (37 lb ft).


    Object Number: 1670483  Size: SH
  12. Install the exhaust hanger to the rear suspension support bracket bolts.
  13. Tighten
    Tighten the bolts to 30 N·m (22 lb ft).

  14. Tighten the catalytic converter to the rear exhaust manifold pipe nuts previously installed.
  15. Tighten
    Tighten the nuts to 25 N·m (18 lb ft).


    Object Number: 1670531  Size: SH
  16. If reusing the old HO2S, coat the threads with anti-seize compound, GM P/N 12377953 or equivalent.
  17. Install the HO2S.
  18. Tighten
    Tighten the sensor to 41 N·m (30 lb ft).


    Object Number: 1665113  Size: SH
  19. Connect the HO2S electrical connector.
  20. Install the CPA retainer.
  21. Install the oxygen sensor wiring harness heat shield. Refer to Oxygen Sensor Wiring Harness Heat Shield Replacement.