GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Blazer - 4WD - RHD 🢒 Engine 🢒 Engine Controls - 4.3L 🢒 Catalytic Converter Replacement

Removal Procedure
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the transmission support. Refer to Transmission Support Replacement in Frame and Underbody.

    3. Object Number: 543864 Size: SH
  3. Disconnect the LH pre-converter heated oxygen sensor (HO2S) electrical connection.

    4. Object Number: 543854 Size: SH
  4. Disconnect the RH pre-converter heated oxygen sensor (HO2S) electrical connection.

    5. Object Number: 543858 Size: SH
  5. Disconnect the post-converter heated oxygen sensor (HO2S) electrical connection.

    6. Object Number: 535780 Size: SH
  6. Remove the muffler to the catalytic converter flange nuts.
  7. Remove the muffler from the catalytic converter.

    8. Object Number: 42940 Size: SH
  8. Remove the catalytic converter to exhaust manifold flange nuts.

    9. Object Number: 609785 Size: SH
  9. Remove the catalytic converter from the rubber catalytic converter hangers.
  10. Remove the catalytic converter and gasket from the vehicle.
  11. Remove the heated oxygen sensors (HO2S) as necessary.

Installation Procedure

    Object Number: 609785 Size: SH
  1. Install the heated oxygen sensors (HO2S) as necessary.
  2. Install the catalytic converter and new gaskets to the vehicle.
  3. Install the catalytic converter to the catalytic converter rubber hangers.

    4. Object Number: 42940 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.

  4. Install the catalytic converter to exhaust manifold flange nuts.

    5. Tighten
    Tighten the catalytic converter to exhaust manifold nuts to 53 N·m (39 lb ft).


    Object Number: 535780 Size: SH
  5. Install the muffler and new gasket to the catalytic converter.
  6. Install the muffler to the catalytic converter flange nuts.

    7. Tighten
    Tighten the muffler to the catalytic converter flange nuts to 40 N·m (30 lb ft).


    Object Number: 543858 Size: SH
  7. Connect the post-converter heated oxygen sensor (HO2S) electrical connection.

    8. Object Number: 543854 Size: SH
  8. Connect the RH pre-converter heated oxygen sensor (HO2S) electrical connection.

    9. Object Number: 543864 Size: SH
  9. Connect the LH pre-converter heated oxygen sensor (HO2S) electrical connection.
  10. Install the transmission support. Refer to Transmission Support Replacement in Frame and Underbody.
  11. Lower the vehicle.