GM Service Manual Online
For 1990-2009 cars only

Exhaust Manifold Replacement LAT, LE5

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .

  2. Object Number: 1650757  Size: SH

    Notice: Do not bend the exhaust flex decoupler more than 3 degrees in any direction. Movement of more than 3 degrees will damage the exhaust flex decoupler.

  3. Remove the catalytic converter to exhaust manifold nuts.
  4. Pull down and back on the exhaust pipe in order to separate the catalytic converter from the exhaust manifold.
  5. Remove and discard the catalytic converter gasket.

  6. Object Number: 1887322  Size: SH
  7. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .
  8. Remove the outlet duct retaining bracket.
  9. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement .
  10. Remove the HO2S. Refer to Heated Oxygen Sensor 1 Replacement .

  11. Object Number: 1631764  Size: SH
  12. Remove the exhaust manifold nuts.
  13. Remove the exhaust manifold.
  14. Remove and discard the exhaust manifold gasket.
  15. Clean and inspect all gasket mating surfaces.

Installation Procedure


    Object Number: 1631764  Size: SH
  1. Install a NEW exhaust manifold gasket onto the studs.
  2. Install the exhaust manifold to the cylinder head.
  3. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1340643  Size: SH
  4. Install NEW exhaust manifold nuts.
  5. Tighten
    Tighten the nuts in the sequence shown to 14 N·m (10 lb ft).


    Object Number: 1650757  Size: SH
  6. Install a NEW catalytic converter gasket .
  7. Install the catalytic converter to the exhaust manifold studs.
  8. Install the catalytic converter to exhaust manifold nuts.
  9. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).

  10. Lower the vehicle.
  11. Install the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement .
  12. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement .

Exhaust Manifold Replacement LAT or LE5

Removal Procedure

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.

  2. Object Number: 1650757  Size: SH

    Caution: Do not bend the exhaust flex decoupler more than 3 degrees in any direction. Movement of more than 3 degrees will damage the exhaust flex decoupler.

  3. Remove the catalytic converter to exhaust manifold nuts.
  4. Pull down and back on the exhaust pipe in order to separate the catalytic converter from the exhaust manifold.
  5. Remove and discard the catalytic converter gasket.

  6. Object Number: 1887322  Size: SH
  7. Remove the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement.
  8. Remove the outlet duct retaining bracket.
  9. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement.
  10. Remove the HO2S. Refer to Heated Oxygen Sensor 1 Replacement.

  11. Object Number: 1631764  Size: SH
  12. Remove the exhaust manifold nuts.
  13. Remove the exhaust manifold.
  14. Remove and discard the exhaust manifold gasket.
  15. Clean and inspect all gasket mating surfaces.

Installation Procedure


    Object Number: 1631764  Size: SH
  1. Install a NEW exhaust manifold gasket onto the studs.
  2. Install the exhaust manifold to the cylinder head.
  3. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1340643  Size: SH
  4. Install NEW exhaust manifold nuts and tighten to 14 N·m (10 lb ft).

  5. Object Number: 1650757  Size: SH
  6. Install a NEW catalytic converter gasket.
  7. Install the catalytic converter to the exhaust manifold studs.
  8. Install the catalytic converter to exhaust manifold nuts and tighten to 50 N·m (37 lb ft).
  9. Lower the vehicle.
  10. Install the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement.
  11. Install the air cleaner outlet duct. Refer to Air Cleaner Outlet Duct Replacement.