GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.

Caution: Always wear protective goggles and gloves when removing exhaust parts as falling rust and sharp edges from worn exhaust components could result in serious personal injury.


    Object Number: 676711  Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the connector position assurance (CPA) locks.
  3. Disconnect the oxygen sensor electrical connectors.
  4. Remove the oxygen sensor clips to the heat shields.
  5. Notice: Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

  6. Remove the oxygen sensors.

  7. Object Number: 676192  Size: SH
  8. Remove the exhaust manifold nuts.
  9. Install adjustable jack stands under the front and rear of the catalytic converter.

  10. Object Number: 676717  Size: SH
  11. Remove the exhaust pipe hanger lower bolts.

  12. Object Number: 676712  Size: SH
  13. Remove the exhaust pipe brace lower bolts.

  14. Object Number: 676722  Size: SH
  15. Remove the exhaust muffler bolts.
  16. Remove the exhaust muffler gaskets.
  17. Lower the jack stands.

  18. Object Number: 792386  Size: SH
  19. With the aid of an assistant remove the catalytic converter from the jack stands.

Installation Procedure

Notice: When inspecting or replacing exhaust system components, make sure there is adequate clearance from all points on the underbody to prevent overheating of the floor pan and possible damage to the passenger compartment insulation and trim materials.


    Object Number: 792386  Size: SH
  1. With the aid of an assistant install the catalytic converter to the jack stands.
  2. Raise the jack stands in order to position the catalytic converter.
  3. Install NEW exhaust muffler gaskets.
  4. Install ALL exhaust bolts until snug to ensure correct alignment of the catalytic converter.
  5. Remove the adjustable jack stands.

  6. Object Number: 676722  Size: SH

    Notice: Use the correct fastener in the correct location. Replacement fasteners must be the correct part number for that application. Fasteners requiring replacement or fasteners requiring the use of thread locking compound or sealant are identified in the service procedure. Do not use paints, lubricants, or corrosion inhibitors on fasteners or fastener joint surfaces unless specified. These coatings affect fastener torque and joint clamping force and may damage the fastener. Use the correct tightening sequence and specifications when installing fasteners in order to avoid damage to parts and systems.

  7. Tighten the exhaust muffler bolts in the following sequence:
  8. 6.1. Left inboard
    6.2. Left outboard
    6.3. Right inboard
    6.4. Right outboard

    Tighten
    Tighten the exhaust muffler bolts to 50 N·m (37 lb ft).


    Object Number: 676192  Size: SH
  9. Tighten the exhaust manifold nuts.
  10. Tighten
    Tighten the exhaust manifold nuts to 20 N·m (15 lb ft).


    Object Number: 676712  Size: SH
  11. Tighten the exhaust pipe brace lower bolts.
  12. Tighten
    Tighten the exhaust pipe brace bolts to 50 N·m (37 lb ft).


    Object Number: 676717  Size: SH
  13. Tighten the exhaust pipe hanger lower bolts.
  14. Tighten
    Tighten the exhaust pipe hanger bolts to 50 N·m (37 lb ft).


    Object Number: 676711  Size: SH
  15. Apply anti-sieze compound GM P/N 12377953 or equivalent to the threads of the oxygen sensor.
  16. Notice: Handle the oxygen sensors carefully in order to prevent damage to the component. Keep the electrical connector and the exhaust inlet end free of contaminants. Do not use cleaning solvents on the sensor. Do not drop or mishandle the sensor.

  17. Install the oxygen sensors.
  18. Tighten
    Tighten the oxygen sensors to 42 N·m (30 lb ft).

  19. Install the oxygen sensor clips to the heat shields.
  20. Connect the oxygen sensor electrical connectors.
  21. Install the CPA locks.
  22. Lower the vehicle.