Exhaust Manifold Replacement - Left Side RPO LS4

1. Remove the engine sight shield. Refer to Upper Intake Manifold Sight Shield Replacement .
2. Remove the exhaust crossover pipe heat shield in order to access the cross pipe to the exhaust manifold nuts.
3. Remove the exhaust crossover pipe nuts from the left exhaust manifold.
4. Remove the left side spark plugs. Refer to Spark Plug Replacement .
5. Remove the oil level indicator tube. Refer to Oil Level Indicator and Tube Replacement .



6. Remove the exhaust manifold heat shield bolts (604).
7. Remove the exhaust manifold heat shield (603).
8. Remove the heater hose retainer bolts in order to be able to remove the manifold.



9. Remove the exhaust manifold bolts.
10. Remove the exhaust manifold.
11. Remove and discard the exhaust manifold gasket.
12. Clean and inspect the left exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection .

Important: 

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 in the Preface section.

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

Tighten

•	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 left cylinder head.



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

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

6. Install the oil level indicator tube. Refer to Oil Level Indicator and Tube Replacement .
7. Install the left side spark plugs. Refer to Spark Plug Replacement .



8. Install the exhaust crossover pipe nuts from the left exhaust manifold.

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

9. Install the exhaust crossover pipe heat shield.
10. Install the heater pipe retainer bolts.

Tighten
Tighten the bolts to 16 N·m (12 lb ft).

11. Install the engine sight shield. Refer to Upper Intake Manifold Sight Shield Replacement .

Exhaust Manifold Replacement - Left Side RPOs LZE/LZ4/LZ8

1. Remove the engine mount strut bracket. Refer to Engine Mount Strut Bracket Replacement - Left Side .
2. Remove the exhaust manifold heat shield bolts.
3. Remove the exhaust manifold heat shield.



4. Remove the exhaust crossover pipe heat shield bolts.
5. Remove the exhaust crossover pipe heat shield.



6. Remove the exhaust crossover pipe to left exhaust manifold nuts.



7. Remove the exhaust manifold bolts.
8. Remove the exhaust manifold bolts.
9. Remove the exhaust manifold.
10. Remove and discard the exhaust manifold gasket.

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

Notice: Refer to Fastener Notice in the Preface section.

3. Install the exhaust manifold bolts.

Tighten
Tighten the bolts to 20 N·m (15 lb ft).




4. Install the exhaust crossover pipe to left exhaust manifold nuts.

Tighten
Tighten the nuts to 20 N·m (15 lb ft).




5. Install the exhaust crossover pipe heat shield.
6. Install the exhaust crossover pipe heat shield bolts.

Tighten
Tighten the bolts to 10 N·m (89 lb in).




7. Install the exhaust manifold heat shield.
8. Install the exhaust manifold heat shield bolts.

Tighten
Tighten the bolts to 10 N·m (89 lb in).

9. Install the engine mount strut bracket. Refer to Engine Mount Strut Bracket Replacement - Left Side .