Removal Procedure
- Raise the vehicle. Refer to
Lifting and Jacking the Vehicle
in General Information.
- Disconnect the exhaust pipe from the exhaust manifold. Refer to
Exhaust Manifold Pipe Replacement
.
- Lower the vehicle.
- Remove the bolt for the oil level indicator tube.
Notice: Twist the spark plug boot one-half turn in order to release the boot.
Pull on the spark plug boot only. Do not pull on the spark plug wire or the
wire could be damaged.
- Remove the spark plug wires from the spark plugs.
5.1. | Rotate the spark plug wire boot ½ turn. |
5.2. | Pull outward on the spark plug wire boot to release from the spark
plug. |
- Remove the spark plug wires from the spark plug wire retainers.
- Remove the exhaust manifold bolts.
- Remove the spark plug wire shields and the exhaust manifold.
- Remove and discard the
exhaust manifold gaskets.
- Clean all gasket surfaces. Refer to
Exhaust Manifold Cleaning and Inspection
in Engine Mechanical
- 4.3L Unit Repair.
Installation Procedure
Important: To assist in installing the exhaust manifold to the engine, the tabs
at the bolt holes on a NEW exhaust manifold gasket will hold the bolts and
the gaskets in place.
- Sub-assemble the bolts, spark plug wire shields, and NEW gaskets to
the exhaust manifold.
- Ensure that the exhaust manifold bolts are held in place by the
tabs on the exhaust manifold gaskets.
- Install the exhaust manifold.
- Install the spark plug wire shields.
- If reusing the fasteners, apply threadlock GM P/N 12345493 (Canadian P/N 10953488)
or equivalent to the threads of the exhaust manifold bolts.
Notice: Use the correct fastener in the correct location. Replacement fasteners
must be the correct part number for that application. Fasteners requiring
replacement or fasteners requiring the use of thread locking compound or sealant
are identified in the service procedure. Do not use paints, lubricants, or
corrosion inhibitors on fasteners or fastener joint surfaces unless specified.
These coatings affect fastener torque and joint clamping force and may damage
the fastener. Use the correct tightening sequence and specifications when
installing fasteners in order to avoid damage to parts and systems.
- Install the exhaust manifold bolts.
Tighten
- Tighten the exhaust manifold bolts on the first pass to 15 N·m
(11 lb ft).
- Tighten the exhaust manifold bolts on the final pass to 30 N·m
(22 lb ft).
- Install the spark plug wires to the spark plug wire retainers.
- Install the spark plug wires onto the spark plugs.
- Raise the vehicle. Refer to
Lifting and Jacking the Vehicle
in General Information.
- Connect the exhaust pipe to the exhaust manifold. Refer to
Exhaust Manifold Pipe Replacement
.
- Lower the vehicle.
- Install the bolt for the oil level indicator tube.
Tighten
Tighten the oil level indicator tube bolt to 12 N·m (106 lb in).