Installation Procedure

WARNING: This page does not describe the selected car, but rather 6 other vehicles, including the 2004 Oldsmobile Bravada, 2004 GMC Envoy XUV, 2004 GMC Envoy XL, 2004 GMC Envoy, and 2004 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.

IMPORTANT:

Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or On-Board Diagnostics (OBD) II system performance.
The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or thread locking material.

IMPORTANT: Do not apply sealant to the first three threads of the bolt.

Fig 1: Removing/Installing Exhaust Manifold

Courtesy of GENERAL MOTORS CORP.

NOTE: Refer to Fastener Notice in Cautions and Notices.

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.
Install the exhaust manifold, NEW gasket and bolts.
Tighten:
1. Tighten the bolts a first pass to 15 N.m (11 lb ft). Tighten the bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
2. Tighten the bolts a final pass to 25 N.m (18 lb ft). Tighten the bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
Install the heat shield, and bolts to the exhaust manifold.
Tighten: Tighten the bolts to 9 N.m (80 lb in).
Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the left cylinder head.
Install the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 4.8L, 5.3L, and 6.0L.
Raise the vehicle.

Fig 2: View Of Left Catalytic Converter To The Exhaust Manifold Connection

Courtesy of GENERAL MOTORS CORP.

Install the exhaust manifold pipe nuts.
Tighten: Tighten the nuts to 50 N.m (37 lb ft).
Lower the vehicle.