Exhaust Manifold Replacement - Right Side

Exhaust Manifold Replacement - Right Side (LZE-3.5L Flex Fuel/LZ4-3.5L Gas/LZ8-3.9L Flex Fuel)

Special Tools

J 39194-B Heated Oxygen Sensor Socket

Removal Procedure




1. Remove the generator. Refer to Generator Replacement (LS4) (Service and Repair)Generator Replacement (RPOs LZE/LZ4/LZ8) (Service and Repair).
2. Remove the connector position assurance (CPA) retainer (3).
3. Disconnect the heated oxygen sensor (HO2S) electrical connector (2).
4. Remove the HO2S clip (1) from the ignition coil bracket.





Note: The HO2S uses a permanently attached pigtail and connector. This pigtail should not be removed from the sensor. Damage or removal of the pigtail or connector will affect proper operation of the sensor.

5. Remove the HO2S using the J 39194-B .




6. Remove the exhaust manifold shield bolts.
7. Remove the exhaust manifold shield.




8. Remove the exhaust crossover pipe heat shield bolts.
9. Remove the exhaust crossover pipe heat shield.




10. Remove the exhaust crossover pipe to right exhaust manifold nuts.




11. Remove the upper exhaust manifold bolts.
12. Remove the catalytic converter. Refer to Catalytic Converter Replacement (With LZE, NU6 and PZEV) (Service and Repair).
13. Remove the lower exhaust manifold bolts.
14. Remove the exhaust manifold.
15. Remove and discard the exhaust manifold gasket.

Installation Procedure




1. Install a NEW exhaust manifold gasket onto the cylinder head studs.
2. Install the exhaust manifold.

Caution: Refer to Fastener Caution (Fastener Caution).

3. Install the lower exhaust manifold bolts.

Tighten the bolts to 20 Nm (15 lb ft).

4. Install the catalytic converter. Refer to Catalytic Converter Replacement (With LZE, NU6 and PZEV) (Service and Repair).
5. Lower the vehicle.
6. Install the upper exhaust manifold bolts.

Tighten the bolts to 20 Nm (15 lb ft).




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




8. Install the exhaust crossover pipe heat shield.
9. Install the exhaust crossover pipe heat shield bolts.




10. Install the exhaust manifold shield.
11. Install the exhaust manifold shield bolts.

Tighten the bolts to 10 Nm (89 lb in).





Note: Whenever the oxygen sensor is removed, coat the threads with nickel-based anti-seize compound such as GM P/N 5613695 (or equivalent).

12. Install the HO2S using J 39194-B .

Tighten the sensor to 42 Nm (31 lb ft).




13. Connect the HO2S electrical connector (2).
14. Install the CPA retainer (3).
15. Install the HO2S clip (1) to the ignition coil bracket.
16. Install the generator. Refer to Generator Replacement (LS4) (Service and Repair)Generator Replacement (RPOs LZE/LZ4/LZ8) (Service and Repair).