GM Service Manual Online
For 1990-2009 cars only

Catalytic Converter Replacement - Left Side LH8

Removal Procedure

  1. Remove catalytic convertor guard. Refer to Catalytic Converter Guard Replacement.
  2. 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.

  3. Object Number: 1902479  Size: SH
  4. Remove the catalytic converter to muffler nuts (1).
  5. Loosen the muffler to catalytic converter clamp (2).

  6. Object Number: 1902480  Size: SH
  7. With the aid of an assistant, separate the muffler hangers from the insulators (1).
  8. Separate the muffler from the catalytic converters.
  9. Reposition the muffler (2) rearward as far as possible, and support using the rear axle and jack stands.

  10. Object Number: 1903038  Size: SH
  11. Remove the catalytic converter to exhaust manifold nuts (2).
  12. 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 (2).
  4. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).


    Object Number: 1902480  Size: SH
  5. With the aid of an assistant, remove the muffler (2) from the jack stands.
  6. Install the muffler to the catalytic converters.
  7. Install the muffler hangers to the insulators (1).

  8. Object Number: 1902479  Size: SH
  9. Install the catalytic converter to muffler nuts (1).
  10. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  11. Tighten the muffler to catalytic converter clamp (2).
  12. Tighten
    Tighten the clamp to 43 N·m (32 lb ft).

  13. Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 and Heated Oxygen Sensor Replacement - Bank 1 Sensor 2.
  14. Install catalytic convertor guard. Refer to Catalytic Converter Guard Replacement.
  15. Inspect exhaust system for leaks.