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For 1990-2009 cars only

Catalytic Converter Replacement 3.5L Twin Cam V6 LX5

Removal Procedure

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect the heated oxygen sensor (HO2S) wiring harness connector and retainers.
  3. Notice: To prevent internal damage to the flexible coupling of the catalytic converter assembly, the converter must be supported. The vertical movement at the rear of the catalytic converter assembly must not exceed 6 degrees up or down.

  4. Suitably support the exhaust system.

  5. Object Number: 372616  Size: SH
  6. Remove the catalytic converter bolts.
  7. Remove the catalytic converter gasket.

  8. Object Number: 407377  Size: SH
  9. Remove the right (rear) exhaust manifold pipe stud nuts from the exhaust manifold pipe studs.
  10. Remove the three-way catalytic converter pipe.
  11. Remove the exhaust manifold pipe gasket.

  12. Object Number: 372612  Size: SH
  13. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.5L.

Installation Procedure


    Object Number: 372612  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.

  1. Install the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.5L.

  2. Object Number: 407377  Size: SH
  3. Install the exhaust manifold gasket.
  4. Notice: To prevent internal damage to the flexible coupling of the catalytic converter assembly, the converter must be supported. The vertical movement at the rear of the catalytic converter assembly must not exceed 6 degrees up or down.

  5. Install the three-way catalytic converter.
  6. 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. Install the right (rear) exhaust manifold pipe stud nuts to the exhaust manifold pipe studs.
  8. Tighten
    Tighten the right (rear) exhaust manifold pipe stud nuts to 6 N·m (53 lb in).


    Object Number: 372616  Size: SH
  9. Install the catalytic converter gasket.
  10. Install the catalytic converter bolts.
  11. Tighten
    Tighten the catalytic converter bolts to 45 N·m (33 lb ft).

  12. Remove the support from the exhaust system.
  13. Connect the heated oxygen sensor (HO2S) wiring harness connector and retainers.
  14. Lower the vehicle.
  15. Inspect for exhaust system leaks and underbody contact.

Catalytic Converter Replacement 3800 V6 L36

Removal Procedure

The three way catalytic converter is serviced by replacing the entire assembly. Always replace the gaskets at the front and rear flanges when servicing the three way catalytic converter assembly. Never reinstall the original gasket.

  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Disconnect the heated oxygen sensor wiring harness connector and retainers.
  3. Notice: To prevent internal damage to the flexible coupling of the catalytic converter assembly, the converter must be supported. The vertical movement at the rear of the catalytic converter assembly must not exceed 6 degrees up or down.

  4. Suitably support the exhaust system.

  5. Object Number: 372616  Size: SH
  6. Remove the catalytic converter bolts.
  7. Remove the catalytic converter gasket.

  8. Object Number: 372626  Size: SH
  9. Remove the exhaust manifold pipe stud nuts.
  10. Remove the three way catalytic converter.
  11. Remove the exhaust manifold pipe gasket at the exhaust manifold pipe studs.

  12. Object Number: 372612  Size: SH
  13. Remove the heated oxygen sensor. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.

Installation Procedure


    Object Number: 372612  Size: SH
  1. Install the heated oxygen sensor. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.

  2. Object Number: 372626  Size: SH
  3. Install a new exhaust manifold pipe gasket to the exhaust manifold pipe studs.
  4. Notice: To prevent internal damage to the flexible coupling of the catalytic converter assembly, the converter must be supported. The vertical movement at the rear of the catalytic converter assembly must not exceed 6 degrees up or down.

  5. Install and support the three way catalytic converter.
  6. 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. Install the exhaust manifold pipe stud nuts.
  8. Tighten
    Tighten the exhaust manifold pipe stud nuts to 35 N·m (26 lb ft).


    Object Number: 372616  Size: SH
  9. Install the catalytic converter gasket.
  10. Install the catalytic converter bolts.
  11. Tighten
    Tighten the catalytic converter bolts to 45 N·m (33 lb ft).

  12. Connect the heated oxygen sensor wiring harness connector and retainers.
  13. Remove the support from the exhaust system.
  14. Lower the vehicle.
  15. Inspect the exhaust system for leaks and underbody contact.