Sierra 1500 2WD V8-5.3L Hybrid (2004)
1. Install the heat shield (2), and bolts (1) to the exhaust manifold (1), if necessary.
Tighten the bolts to 9 Nm (80 inch lbs.).
2. Important:
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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.
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The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.
Important: Do not apply sealant to the first three threads of the bolt.
Apply a 5 mm (0.2 inch) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent to the threads of the exhaust
manifold bolts.
3. Install the exhaust manifold, NEW gasket and bolts.
1. Tighten the bolts a first pass to 15 Nm (11 ft. lbs.). Tighten the bolts beginning with the center 2 bolts. Alternate from side-to-side, and work
toward the outside bolts.
2. Tighten the bolts a final pass to 25 Nm (18 ft. lbs.). Tighten the bolts beginning with the center 2 bolts. Alternate from side-to-side, and work
toward the outside bolts.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the front of the right cylinder head.
5. Install the spark plugs.
6. Raise the vehicle.
7. Install the exhaust manifold pipe nuts.
Tighten the nuts to 50 Nm (37 ft. lbs.).
8. Lower the vehicle.
