GM Service Manual Online
For 1990-2009 cars only

Exhaust Manifold Replacement LL8

Removal Procedure


    Object Number: 750208  Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the catalytic converter to exhaust manifold nuts (2).
  3. Lower the vehicle.
  4. Remove the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement .

  5. Object Number: 1906287  Size: SH
  6. Remove the exhaust manifold bolts.
  7. Remove the exhaust manifold.

  8. Object Number: 637622  Size: SH
  9. Remove the exhaust manifold gasket.

Installation Procedure


    Object Number: 637622  Size: SH
  1. Position a NEW exhaust manifold gasket to the cylinder head.

  2. Object Number: 1906287  Size: SH
  3. Position the exhaust manifold to the cylinder head and install the studs to the catalytic converter.
  4. Apply threadlock GM P/N 12345493 (Canadian P/N 10953488) to the exhaust manifold bolt threads.
  5. Install the exhaust manifold bolts.
  6. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1906301  Size: SH
  7. Tighten the exhaust manifold bolts in the sequence shown.
  8. Tighten

    1. Tighten the bolts first pass in sequence to 20 N·m (15 lb ft).
    2. Tighten the bolts second pass in sequence to 20 N·m (15 lb ft).
    3. Tighten the bolts final pass in sequence to 20 N·m (15 lb ft).

    Object Number: 1922943  Size: SH
  9. Install the exhaust manifold heat shield. Refer to Exhaust Manifold Heat Shield Replacement .
  10. Raise the suitably support the vehicle.
  11. Install the catalytic converter to exhaust manifold nuts (2).
  12. Tighten
    Tighten the nuts to 50 N·m (37 lb ft).

  13. Lower the vehicle.