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For 1990-2009 cars only

Catalytic Converter Replacement LL8

Removal Procedure


    Object Number: 1922948  Size: SH
  1. Remove the heated oxygen sensors (H2OS). Refer to Heated Oxygen Sensor 1 Replacement and Heated Oxygen Sensor 2 Replacement.
  2. Remove the transmission mount. Refer to Transmission Mount Replacement.
  3. Remove the catalytic converter to muffler nuts (1).

  4. Object Number: 1923248  Size: SH
  5. Remove the front 2 muffler insulators (3 and 4) from the muffler hangers.
  6. Pull back and separate the muffler (2) flange studs from the catalytic converter flange.
  7. Reposition and secure the muffler end out of the way.
  8. Remove and discard the old exhaust gasket.

  9. Object Number: 1922943  Size: SH
  10. Remove the catalytic converter to exhaust manifold nuts (2).
  11. Remove the catalytic converter (3) from the vehicle.
  12. Remove and discard the old exhaust seal (1).

  13. Object Number: 1923249  Size: SH
  14. Remove the catalytic converter hanger (1) from the catalytic converter.

Installation Procedure


    Object Number: 1923249  Size: SH
  1. Install the catalytic converter hanger (1) to the catalytic converter.

  2. Object Number: 1922943  Size: SH
  3. Install a NEW exhaust seal (1) into the exhaust manifold.
  4. Install the catalytic converter (3) to the vehicle.
  5. Caution: Refer to Fastener Caution in the Preface section.

  6. Install the catalytic converter to exhaust manifold nuts (2).
  7. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).


    Object Number: 1923248  Size: SH
  8. Unsecure and position the muffler assembly.
  9. Install a NEW exhaust gasket onto the muffler studs.
  10. Pull back and install the muffler (2) flange studs to the catalytic converter flange.
  11. Install the front 2 muffler insulators (3 and 4) to the muffler hangers.

  12. Object Number: 1922948  Size: SH
  13. Install the catalytic converter to muffler nuts (1).
  14. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  15. Install the transmission mount. Refer to Transmission Mount Replacement.
  16. Install the H2OS. Refer to Heated Oxygen Sensor 1 Replacement and Heated Oxygen Sensor 2 Replacement.

Catalytic Converter Replacement LH6/LS2

Removal Procedure


    Object Number: 1922951  Size: SH
  1. Remove the heated oxygen sensors (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 , Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 , Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 , and Heated Oxygen Sensor Replacement - Bank 2 Sensor 2.
  2. Remove the rear propeller shaft. Refer to Rear Propeller Shaft Replacement.
  3. If equipped with four wheel drive (4WD), remove the front propeller shaft. Refer to Front Propeller Shaft Replacement.
  4. Remove the transmission support. Refer to Transmission Support Replacement.
  5. Remove the muffler to catalytic converter nuts (1).

  6. Object Number: 1923248  Size: SH
  7. Remove the front 2 muffler insulators (3 and 4) from the muffler hangers.
  8. Pull back and separate the muffler (2) flange from the catalytic converter flange studs.
  9. Reposition and secure the muffler end out of the way.
  10. Remove and discard the old exhaust gasket.

  11. Object Number: 1922949  Size: SH
  12. Remove the catalytic converter to left exhaust manifold nuts (2).

  13. Object Number: 1922950  Size: SH
  14. Remove the catalytic converter to right exhaust manifold nuts (2).

  15. Object Number: 1923281  Size: SH
  16. Raise the transmission using the transmission jack for additional catalytic converter pipe clearance.
  17. Tilt the catalytic converter in order to lower the left side pipe below the vehicle frame. Rotate the catalytic converter outlet pipe toward the left side of the vehicle to gain the necessary clearance for the right side pipe to clear the vehicle frame. Remove the catalytic converter (1) from the vehicle.
  18. Remove and discard the catalytic converter to exhaust manifold seals.

Installation Procedure


    Object Number: 1923281  Size: SH
  1. Install the catalytic converter in reverse order of removal by starting with the catalytic converter outlet pipe angled toward the left side of the vehicle and positioning the right side pipe above the frame. Rotate the catalytic converter outlet pipe toward the rear of the vehicle and lift the left side pipe up above the frame.
  2. Install a NEW exhaust seal to the right exhaust manifold.
  3. Install a NEW exhaust seal onto the groove on the catalytic converter left side flange.
  4. Install the catalytic converter (1) to the exhaust manifold studs.
  5. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1922950  Size: SH
  6. Install the catalytic converter to right exhaust manifold nuts (2).
  7. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).


    Object Number: 1922949  Size: SH
  8. Install the catalytic converter to left exhaust manifold nuts (2).
  9. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).


    Object Number: 1923248  Size: SH
  10. Unsecure and position the muffler assembly.
  11. Install a NEW exhaust gasket onto the catalytic converter studs.
  12. Pull back and install the muffler (2) flange onto the catalytic converter flange studs.
  13. Install the front 2 muffler insulators (3 and 4) to the muffler hangers.

  14. Object Number: 1922951  Size: SH
  15. Install the muffler to catalytic converter nuts (1).
  16. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  17. Install the transmission support. Refer to Transmission Support Replacement.
  18. If equipped with 4WD, install the front propeller shaft. Refer to Front Propeller Shaft Replacement.
  19. Install the rear propeller shaft. Refer to Rear Propeller Shaft Replacement.
  20. Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 , Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 , Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 , and Heated Oxygen Sensor Replacement - Bank 2 Sensor 2.