Installation Procedure
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2011 GMC Yukon XL, 2011 GMC Yukon, 2011 Chevrolet Tahoe, 2011 Chevrolet Suburban, and 2011 Chevrolet Avalanche. However, it is still accessible from the selected car via links, so may be relevant.
NOTE:
- 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 threadlocking material.
- Do not apply sealant to the first 3 threads of the bolt.
- If the exhaust manifold was replaced, position and install the exhaust manifold heat shield, and bolts to the exhaust manifold.
Tighten
Tighten the bolts to 9 N.m (80 lb in).
- Clean the threads of the exhaust manifold bolts.
- 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 a NEW catalytic converter seal to the exhaust manifold.
- Position the NEW exhaust manifold gasket and exhaust manifold to the cylinder head.
- Ensure that the catalytic converter seal is seated to the catalytic converter.
- Install the exhaust manifold bolts.
Tighten
- Tighten the bolts a first pass to 15 N.m (11 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
- Tighten the bolts a final pass to 20 N.m (15 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
- Using a flat punch, bend the gasket tab at the rear of the gasket around the cylinder head edge.
- Install the oil level indicator tube to the engine block. Refer to Oil Level Indicator Tube Replacement .
- Install the spark plug wires (1) to the spark plugs.
- Install the spark plug wires to the ignition coils.
- Inspect the spark plug wires for proper installation.
- Push sideways on each boot in order to inspect the seating.
- Reinstall any loose boot.
- Fully raise and support the vehicle.
- Install the catalytic converter to exhaust manifold nuts. (1500 series shown, 2500 series similar).
Tighten
Tighten the nuts to 50 N.m (37 lb ft).
- Partially lower the vehicle in order to work through the wheel opening.
- Install the front wheel house liner - right front. Refer to Front Wheelhouse Liner Replacement - Right Side .
- Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (1500 Series) , Heated Oxygen Sensor Replacement - Bank 2 Sensor 1 (2500 Series) .
- Inspect the exhaust system for leaks.
CAUTION:
Refer to Fastener Caution .