Exhaust System Replacement 3.4L

1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Disconnect the heated oxygen sensor (HO2S) wiring harness connector and retainers. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.4L.

Notice: Refer to Catalytic Converter Movement Notice in the Preface section.

3. Suitably support the exhaust system.
4. Disconnect the exhaust system hangers from the exhaust system.



5. Remove the catalytic converter bolts from the catalytic converter pipe flange.



6. Remove the exhaust system.



7. Remove the exhaust manifold pipe stud nuts from the exhaust manifold pipe studs.
8. Remove the three-way catalytic converter.
9. Remove the exhaust manifold pipe gasket.



10. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.4 L.

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.

1. Install the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.4 L.



2. Install the exhaust manifold pipe gasket.

Notice: Refer to Catalytic Converter Movement Notice in the Preface section.

3. Install the three-way catalytic converter.
4. Install the exhaust manifold pipe stud nuts to the exhaust manifold pipe studs.

Tighten
Tighten the exhaust manifold pipe stud nuts to 32 N·m (24 lb ft).




5. Install the exhaust system.
6. Connect the exhaust system hangers to the exhaust system.



7. Install the catalytic converter gasket and the catalytic converter bolts.

Tighten
Tighten the catalytic converter bolts to 45 N·m (33 lb ft).

8. Remove the support from the exhaust system.
9. Connect the heated oxygen sensor (HO2S) wiring harness connector and retainers. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.4L.
10. Inspect the exhaust system for leaks and underbody contact.
11. Lower the vehicle.

Exhaust System Replacement 3.8L

1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Disconnect the heated oxygen sensor (HO2S) wiring harness connector and retainers. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.

Notice: Refer to Catalytic Converter Movement Notice in the Preface section.

3. Suitably support the exhaust system.
4. Disconnect the exhaust system hangers from the exhaust system.
5. Remove the catalytic converter bolts from the catalytic converter pipe flange.



6. Remove the exhaust system.



7. Remove the exhaust manifold pipe stud nuts from the exhaust manifold pipe studs.
8. Remove the catalytic converter.
9. Remove the exhaust manifold pipe gasket.



10. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.

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.

1. Install the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.



2. Install the exhaust manifold pipe gasket.
3. Install the three-way catalytic converter.
4. Install the exhaust manifold pipe stud nuts to the exhaust manifold pipe studs.

Tighten
Tighten the exhaust manifold pipe stud nuts to 35 N·m (26 lb ft).

Notice: Refer to Catalytic Converter Movement Notice in the Preface section.




5. Install the exhaust system.
6. Connect the exhaust system hangers to the exhaust system.



7. Install the catalytic converter gasket and the catalytic converter bolts.

Tighten
Tighten the catalytic converter bolts to 45 N·m (33 lb ft).

8. Remove the support from the exhaust system.
9. Connect the HO2S wiring harness connector and retainers. Refer to Heated Oxygen Sensor Replacement in Engine Controls - 3.8L.
10. Inspect the exhaust system for leaks and underbody contact.
11. Lower the vehicle.