Exhaust Manifold Replacement - Right Side 4.8 L, 5.3 L, and 6.0 L Engines
- Raise and suitably support the vehicle. Refer to
Lifting and Jacking the Vehicle
.
- Remove the exhaust manifold pipe nuts.
- Lower the vehicle.
- Remove the spark plugs. Refer to
Spark Plug Replacement
.
- Remove the bolts (1, 2, 3) attaching the exhaust gas recirculation (EGR) valve pipe to the following:
- Remove the EGR valve pipe and gaskets.
With mild force, pull the EGR valve pipe from the intake manifold.
- Remove the O-ring seal from the EGR valve pipe.
- Discard the gasket and the O-ring seal.
- Remove the secondary air injection (AIR) check valve pipe (crossover) bolt.
- Reposition the AIR check valve pipe (crossover) hose spring clamps.
- Remove the AIR check valve pipe (crossover) (1) from the check valves.
Important: Do not remove the check valve from the AIR pipe unless valve replacement is required.
- Remove the AIR check valve pipe nuts (2), pipe (with check valve) (4) , and gasket (3) from the right exhaust manifold.
- Remove the exhaust manifold bolts, manifold, and gasket.
- Discard the gasket and bolts.
- If necessary, remove the heat shield bolts (1), and shield (2)
from the exhaust manifold (1).
Installation Procedure
- Install the exhaust manifold to the cylinder head. Refer to
Exhaust Manifold Installation - Right Side
.
Notice: Refer to Fastener Notice in the Preface section.
- Install a NEW AIR check valve pipe gasket (3), the nuts (2), and pipe (with check valve) (4) to the right exhaust manifold.
Tighten
Tighten the AIR check valve pipe nuts to 25 N·m (18 lb ft).
- Install the AIR check valve pipe (crossover) (1) to the check valves.
- Position the AIR check valve pipe (crossover) hose spring clamps.
- Install the AIR check valve pipe (crossover) bolt.
Tighten
Tighten the AIR check valve pipe (crossover) bolt to 50 N·m (37 lb ft).
- Apply a light coating of clean engine oil to a NEW O-ring seal and install the seal onto the EGR valve pipe.
- Install the EGR pipe.
- Install the EGR valve pipe bolts until snug.
Tighten
- Tighten the EGR valve pipe to intake manifold bolt (1) to 10 N·m (89 lb in).
- Tighten the EGR valve pipe to cylinder head bolts (2) to 50 N·m (37 lb ft).
- Tighten the EGR valve pipe to exhaust manifold bolts (3) to 30 N·m (22 lb ft).
- Install the spark plugs. Refer to
Spark Plug Replacement
.
- Raise the vehicle.
- Install the exhaust manifold pipe nuts.
Tighten
Tighten the exhaust manifold pipe nuts to 50 N·m (37 lb ft).
- Lower the vehicle.
Exhaust Manifold Replacement - Right Side 4.3 L
Removal Procedure
- Raise the vehicle. Refer
to
Lifting and Jacking the Vehicle
in General Information.
- Remove the right exhaust manifold pipe nuts.
- Lower the vehicle.
- Separate the MAF/IAT sensor
assembly and the air inlet tube by loosening the hose clamp.
- Disconnect the PCV hose from the air cleaner outlet duct.
- Remove the air inlet tube
and resonator retaining wing nut.
- Remove the air inlet tube
and resonator from the throttle body by pivoting the air inlet tube and resonator
upward until the hinge clip releases from the lip on the throttle body.
- Remove the secondary air injection (AIR) pipe assembly, if equipped
from the exhaust manifold.
- Disconnect the spark plug wires from the spark plugs.
- Remove the spark plug wires from the spark plug wire retainers.
- Remove the exhaust manifold bolts.
- Remove the exhaust manifold.
- Remove and discard the
exhaust manifold gaskets.
- Remove the bolts and the
spark plug wire shield, if necessary.
- Clean all gasket surfaces.
Installation Procedure
- Install the spark plug
wire shield to the exhaust manifold, if removed.
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 heat
shield bolts.
Tighten
Tighten the heat shield bolts to 9 N·m (80 lb in).
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.
- Install the NEW exhaust manifold 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.
- If reusing the fasteners, apply threadlock GM P/N 12345493
or equivalent to the threads of the exhaust manifold bolts.
- 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 AIR pipe assembly, if equipped to the exhaust manifold.
- Install the spark plug wires to the spark plug wire retainers.
- Connect the spark plug wires to the spark plugs.
- Raise the vehicle. Refer to
Lifting and Jacking the Vehicle
in General Information.
- Install NEW exhaust manifold
pipe seals to the exhaust manifolds.
- Install the right exhaust manifold pipe nuts until sung.
- Tighten the exhaust manifold pipe nuts.
Tighten
Tighten the exhaust manifold pipe nuts to 50 N·m (37 lb ft).
- Lower the vehicle.
- Align the hinge clip with
the lip on the throttle body.
Install the air inlet tube and resonator to the throttle body by pivoting
the air inlet tube and resonator downward until the mounting stud is through
the hole in the air inlet tube.
- Install the resonator
retaining wing nut.
- Connect the PCV hose to the air cleaner outlet duct.
- Connect the MAF/IAT sensor
assembly harness connector.
Exhaust Manifold Replacement - Right Side 6.6 L
Removal Procedure
- Raise the vehicle in order to work through the front fender wheelhouse opening. Refer to
Lifting and Jacking the Vehicle
in General Information.
- Remove the right front fender wheelhouse inner panel (1).
- Remove the right front tire and wheel assembly if necessary. Refer to
Tire and Wheel Removal and Installation
in Tires and Wheels.
- Remove the bolts for the exhaust manifold heat shield.
- Remove the exhaust manifold heat shield.
- Remove the bolts (1) retaining the right exhaust pipe to the exhaust manifold.
- Remove the 2 nuts and 6 bolts with plain washer and bell view washer from the
right exhaust manifold.
- Remove the exhaust manifold.
- Remove the bolt for the oil level indicator tube bracket in order to remove the exhaust manifold gasket.
- Remove the exhaust manifold gasket and discard.
Inspection and Repair
- Clean the exhaust manifold.
- Clean the exhaust manifold mating surfaces.
- Inspect the exhaust manifold for cracks.
- Inspect the exhaust manifold mating surfaces for damage.
- Replace the exhaust manifold if any damage is found.
- Measure the exhaust manifold flange for warpage with feeler gauge and a straightedge. Replace the exhaust
manifold if the warpage is more than 0.3 mm (0.0118 in).
- Replace the exhaust manifold if warpage is more than the limits.
Installation Procedure
- Install the exhaust manifold gasket to the cylinder head.
Notice: Refer to Fastener Notice in the Preface section.
- Install the bolt for the oil level indicator tube bracket.
Tighten
Tighten the bracket bolt to 21 N·m (15 lb ft).
- Install the exhaust manifold to the cylinder head.
- Install the exhaust manifold bolts and nuts with the bell view washers and the plain washers.
- Use the sequence shown to properly tighten the exhaust manifold bolts.
Tighten
- Tighten the exhaust manifold nuts and bolts to 34 N·m (25 lb ft) in the proper sequence.
- Tighten the exhaust manifold nuts and bolts again to 34 N·m (25 lb ft) in the proper sequence.
- Install the exhaust manifold heat shield.
- Install the exhaust manifold heat shield bolts.
Tighten
Tighten the exhaust manifold heat shield bolts to 8 N·m (71 lb in).
- Install the exhaust pipe gasket. Align the tab on the gasket to face outward as shown.
- Install the exhaust pipe and the bolts (1) to the exhaust manifold.
Tighten
Tighten the exhaust pipe to manifold bolts to 53 N·m (39 lb ft).
- Install the right front fender wheelhouse inner panel (1).
- Install the right front tire and wheel, if removed. Refer to
Tire and Wheel Removal and Installation
in Tires and Wheels.
- Lower the vehicle.
Exhaust Manifold Replacement - Right Side 8.1 L Engine
Removal Procedure
- Remove the wheelhouse
panel. Refer to
Wheelhouse Panel Replacement
in Body Front End.
- Remove the oil level indicator. Refer to
Oil Level Indicator and Tube Replacement
in Engine Mechanical
- 8.1 L.
- Remove the secondary air injection (AIR) pipe nut from the fuel
rail stud, if equipped.
- Remove the AIR pipe bolts from the exhaust manifold, if equipped.
- Disconnect the AIR pipe from the AIR pump pipe, if equipped.
- Remove the AIR pipe, if equipped.
- Remove and discard the AIR pipe gasket, if equipped.
- Remove the AIR pump pipe
bolt from the cylinder head, if equipped.
- Disconnect the AIR pump pipe from the left AIR pipe, if equipped.
- Remove the AIR pump pipe, if equipped.
Important: 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 or the wire
could be damaged.
- Remove the spark plug wires from the spark plugs and ignition coils.
- Remove the spark plugs. Refer to
Spark Plug Replacement
in Engine Controls - 8.1 L.
- Remove the exhaust gas
recirculation (EGR) pipe nuts from the exhaust manifold.
- Remove the EGR pipe bracket bolt.
- Remove and discard the EGR pipe gasket.
- Reposition the EGR pipe.
- Raise and suitably support the vehicle with safety stands. Refer
to
Lifting and Jacking the Vehicle
in General Information.
- Remove the exhaust manifold
heat shield bolts and nuts.
- Remove the exhaust manifold heat shield.
- Lower the vehicle.
- Remove the exhaust manifold bolt and nuts.
- Remove the exhaust manifold.
- Remove and discard the exhaust manifold gasket.
- Clean and inspect the exhaust manifold. Refer to
Exhaust Manifold Cleaning and Inspection
in Engine Mechanical
- 8.1 L Unit Repair.
Installation Procedure
- Install the a NEW exhaust manifold gasket.
- Install the exhaust manifold.
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 bolt and nuts.
Tighten
• | Tighten the exhaust manifold bolt to 35 N·m (26 lb ft). |
• | Tighten the exhaust manifold nuts to 16 N·m (12 lb ft). |
- Raise and suitably support the vehicle with safety stands.
- install the exhaust manifold
heat shield.
- Install the exhaust manifold heat shield bolts and nuts.
Tighten
Tighten the exhaust manifold heat shield bolts/nuts to 25 N·m
(18 lb ft).
- Lower the vehicle.
- Position the EGR pipe.
- Install a NEW EGR pipe gasket.
- Install the EGR pipe bracket bolt.
Tighten
Tighten the EGR pipe bracket bolt to 50 N·m (37 lb ft).
- Install the EGR pipe nuts to the exhaust manifold.
Tighten
Tighten the EGR pipe nuts to 30 N·m (22 lb ft).
- Install the spark plugs. Refer to
Spark Plug Replacement
in Engine Controls - 8.1 L.
Important: Fully install the spark plug wires by pushing on the exposed end of
the spark plug boot. Do not push the spark plug wire on to the spark plug
by using the metal heat shield.
- Install the spark plug wires to the spark plugs and ignition coils.
- Install the AIR pump pipe,
if equipped.
- Connect the AIR pump pipe to the left AIR pipe, if equipped.
- Install the AIR pump pipe bolt to the cylinder head, if equipped.
Tighten
Tighten the AIR pump pipe bolt to 50 N·m (37 lb ft).
- Install a NEW AIR pipe
gasket, if equipped.
- Install the AIR pipe, if equipped.
- Connect the AIR pipe to the AIR pump pipe, if equipped.
- Install the AIR pipe bolts to the exhaust manifold, if equipped.
Tighten
Tighten the AIR pipe bolt to 25 N·m (18 lb ft).
- Install the AIR pipe nut to the fuel rail stud, if equipped.
Tighten
Tighten the AIR pipe nut to 12 N·m (106 lb in).
- Install the oil level indicator. Refer to
Oil Level Indicator and Tube Replacement
in Engine Mechanical
- 8.1 L.
- Install the wheelhouse panel. Refer to
Wheelhouse Panel Replacement
in Body Front End.