Exhaust Manifold Replacement - Right Side

Exhaust Manifold Replacement - Right Side (RPO LS4) (5.3L)

Removal Procedure





1. Remove the engine sight shield. Refer to Upper Intake Manifold Sight Shield Replacement (Service and Repair) .
2. Remove the spark plugs. Refer to Spark Plug Replacement .
3. Remove the exhaust crossover pipe nuts from the right exhaust manifold.
4. Disconnect the catalytic converter from the exhaust manifold. Refer to Catalytic Converter Replacement (LS4) (Service and Repair)Catalytic Converter Replacement (RPOs LZE/LZ4/LZ8) (Service and Repair) .
5. Support the catalytic convertor and exhaust system with the mechanics wire.
6. Lower the vehicle.
7. Remove the ignition coil. Refer to Ignition Coil Replacement .
8. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 1 .




9. Remove the exhaust manifold heat shield bolts (604).
10. Remove the exhaust manifold heat shield (603).




11. Remove the exhaust manifold bolts.
12. Remove the exhaust manifold.
13. Remove and discard the exhaust manifold gasket.



Installation Procedure

Important:
* Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets my affect vehicle emissions and/or On Board Diagnostic (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 threadlock to the first three thread of the bolts.








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.

Notice: Refer to Fastener Notice .

2. Install a NEW exhaust manifold gasket, the exhaust manifold and bolts.

* Tighten the bolts a first pass to 15 N.m (11 lb ft). Tighten the bolts beginning with the center 2 bolts. Alternate from side to side, and work toward the outside.
* Tighten the bolts a final pass to 20 N.m (15 lb ft). Tighten the bolts beginning with the center 2 bolts. Alternate from side to side, and work toward the outside.


3. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the right cylinder head.




4. Install the exhaust manifold heat shield (603).
5. Install the exhaust manifold heat shield bolts (604).

Tighten the bolts to 9 N.m (80 lb in).

6. Install the O2 sensor. Refer to Spark Plug Replacement .
7. Raise the vehicle.
8. Remove the mechanics wire from the exhaust system and connect the catalytic converter. Refer to Catalytic Converter Replacement (LS4) (Service and Repair)Catalytic Converter Replacement (RPOs LZE/LZ4/LZ8) (Service and Repair) .




9. Install the exhaust crossover pipe nuts to the right exhaust manifold.

Tighten the nuts to 25 N.m (18 lb ft).

10. Install the ignition coil. Refer to Ignition Coil Replacement .
11. Install the spark plugs. Refer to Spark Plug Replacement .
12. Install the fuel injector sight shield. Refer to Upper Intake Manifold Sight Shield Replacement (Service and Repair) .