GM Service Manual Online
For 1990-2009 cars only

Catalytic Converter Replacement - Left Side LH8

Removal Procedure

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

  1. Remove the heated oxygen sensors (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 and Heated Oxygen Sensor Replacement - Bank 1 Sensor 2.

  2. Object Number: 1902479  Size: SH
  3. Remove the catalytic converter to muffler nuts (1).
  4. Loosen the muffler to catalytic converter clamp (2).
  5. With the aid of an assistant, separate the muffler hangers from the insulators.
  6. Separate the muffler from the catalytic converters.
  7. Reposition the exhaust rearward as far as possible, and support using the rear axle and jack stands.

  8. Object Number: 1903038  Size: SH
  9. Remove the catalytic converter to exhaust manifold nuts (2).
  10. Remove the catalytic converter (1) and seal (3).

Installation Procedure


    Object Number: 1903038  Size: SH
  1. Install the catalytic converter (1) and seal (3).
  2. Caution: Refer to Fastener Caution in the Preface section.

  3. Install the catalytic converter to exhaust manifold nuts and tighten to 50 N·m (37 lb ft).
  4. With the aid of an assistant, remove the muffler from the jack stands.
  5. Install the muffler to the catalytic converters.
  6. Install the muffler hangers to the insulators.

  7. Object Number: 1902479  Size: SH
  8. Install the catalytic converter to muffler nuts (1) and tighten to 45 N·m (33 lb ft).
  9. Tighten the muffler to catalytic converter clamp (2) to 43 N·m (32 lb ft).
  10. Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 and Heated Oxygen Sensor Replacement - Bank 1 Sensor 2.
  11. Inspect exhaust system for leaks.