1. Remove the powertrain. Refer to Powertrain Removal and Installation .



2. Remove the bolt (1) securing the catalytic converter pipe to the bell housing.
3. Remove the oxygen sensors. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 and Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 .



4. Remove the right exhaust manifold heat shield bolts (2).
5. Remove the right exhaust manifold heat shield (1).



6. Remove the exhaust manifold bolts and nuts (2).
7. Remove the exhaust manifold, and old gasket. Discard the gasket.

Important: Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may effect vehicle emissions and/or On-Board Diagnostics (OBD) II system performance.

1. Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads of the exhaust manifold bolts and studs.



2. Position the exhaust manifold and a NEW gasket into place.

Notice: Refer to Fastener Notice in the Preface section.




3. Install the exhaust manifold bolts and nuts.

Tighten
Tighten the exhaust manifold bolts and nuts to 25 N·m (18 lb ft). Tighten the exhaust manifold bolts and nuts beginning with the center two nuts. Alternate from side-to-side, working toward the outside bolts and nuts.




4. Install the exhaust manifold and catalytic converter bolt (1) securing the pipe to the bell housing.

Tighten
Tighten the exhaust hanger bolt to 50 N·m (37 lb ft).

5. Install the oxygen sensors. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 and Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 .



6. Install the right exhaust manifold heat shield and bolts.

Tighten
Tighten the exhaust manifold heat shield bolts to 10 N·m (89 lb in).

7. Install the powertrain. Refer to Powertrain Removal and Installation .