Exhaust System Replacement LA3, LY9

Servicing of the muffler, resonator or pipe requires the replacement of the exhaust system as a complete one-piece unit.

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.



2. Remove the 2 bolts securing the floor panel tunnel brace to the floor panel.
3. Remove the floor panel tunnel brace from the floor panel.



4. Remove the nuts securing the exhaust pipe to the left catalytic converter.



5. Remove the nuts securing the exhaust pipe to the right catalytic converter.
6. Suitably support the exhaust system.



7. Pry the front exhaust hanger (1) free from the rear suspension hanger rod.



8. Apply a suitable lubricant to the tail pipe hanger rods in order to ease the removal of the tail pipe hangers (1).
9. Pry the tail pipe hangers (1) free from the tail pipe hanger rods.



10. With the aid of an assistant, lower the exhaust system.
11. Remove the left side catalytic converter seal. Do not reuse the seal.
12. Remove the right side catalytic converter gasket. Do not reuse the gasket.



13. While the exhaust system is on the floor complete the following:
14. Apply a suitable lubricant to the exhaust pipe hanger rod (3) in order to ease the removal of the front exhaust hanger (2).
15. Pull the front exhaust hanger (2) from the exhaust pipe hanger rod.

1. While the exhaust system is on the floor complete the following:

1.1.	Apply a soapy solution to the following in order to ease the installation of the hangers:

•	The inner diameter of the front exhaust hanger (2)

•	The exhaust pipe hanger rod (3)

•	The inner diameter of the tail pipe hangers

•	The tail pipe hanger rods (1)

1.2.	Press the front exhaust hanger (2) over the exhaust pipe hanger rod (3).

2. Place a NEW seal on the left catalytic converter flange.
3. Place a NEW gasket over the right catalytic converter studs.

Notice: Refer to Exhaust System Inspection Notice in the Preface section.

Notice: Refer to Flex Decoupler Notice in the Preface section.




4. With the aid of an assistant, raise the exhaust system into position, aligning the exhaust pipe flanges with the studs located in the rear of the catalytic converters.
5. Finger tighten the 4 nuts to the catalytic converter studs.



6. Press the tail pipe hangers (1) over the tail pipe hanger rods.



7. Press the front exhaust hanger (1) over the rear suspension hanger rod.

Notice: Refer to Fastener Notice in the Preface section.




8. Tighten the 2 left catalytic converter nuts previously installed in step 5.

Tighten
Tighten the catalytic converter nuts to 15 N·m (11 lb ft).




9. Tighten the 2 right catalytic converter nuts previously installed in step 5.

Tighten
Tighten the catalytic converter nuts to 15 N·m (11 lb ft).




10. Position the floor panel tunnel brace to the floor panel.
11. Install the 2 bolts securing the floor panel tunnel brace to the floor panel.

Tighten
Tighten the floor panel tunnel brace bolts to 25 N·m (18 lb ft).

12. Lower the vehicle.

Exhaust System Replacement LY7

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.



2. Disconnect the left and right bank #2 HO2S electrical connectors (bank 1 shown, bank 2 similar).
3. Remove the HO2S wiring harnesses from the transmission case.



4. Remove the muffler nuts and separate the exhaust system from the catalytic converters.



5. Remove the muffler front hanger (1) from the muffler hanger rod.



6. Pry the tail pipe hangers (1) from the muffler rods.



7. Remove the floor panel tunnel brace bolts.
8. Remove the floor panel tunnel brace from the floor panel.



9. With the aid of an assistant, lower the exhaust system.
10. Inspect and replace the exhaust system to catalytic converter seals if excessive wear or damage is noticed.



11. Remove the muffler rear hangers (2) from the muffler(s).
12. Remove the oxygen sensors (HO2S) from the exhaust system. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 and Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 in Engine Controls - 3.6L (LY7).

1. Install the oxygen sensors (HO2S) to the exhaust system. Refer to Heated Oxygen Sensor Replacement - Bank 1 Sensor 2 and Heated Oxygen Sensor Replacement - Bank 2 Sensor 2 in Engine Controls - 3.6L (LY7).



2. Install the muffler rear hangers (2) to the muffler(s).

Notice: Refer to Exhaust System Inspection Notice in the Preface section.

Notice: Refer to Flex Decoupler Notice in the Preface section.




3. With the aid of an assistant, raise the exhaust system into position.
4. Install the exhaust system (muffler) nuts.



5. Install the muffler (1) to the muffler rear hangers.



6. Install the muffler rear hanger (1) to the hanger rod.

Notice: Refer to Fastener Notice in the Preface section.




7. Install the catalytic converter nuts.

Tighten
Tighten the catalytic converter nuts to 15 N·m (11 lb ft).




8. Install the floor panel tunnel brace to the floor panel.
9. Install the floor panel tunnel brace bolts.

Tighten
Tighten the floor panel tunnel brace bolts to 25 N·m (18 lb ft).




10. Connect the left and right bank #2 HO2S electrical connectors (bank 1 shown, bank 2 similar).
11. Install the HO2S wiring harnesses to the transmission case.
12. Lower the vehicle.

Exhaust System Replacement LS6

Servicing of the muffler, resonator or pipe requires the replacement of the exhaust system as a complete one-piece unit.

Caution: Refer to Exhaust Service Caution in the Preface section.

Caution: Refer to Protective Goggles and Glove Caution in the Preface section.

1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
2. Remove the 2 bolts securing the floor panel tunnel brace to the floor panel.
3. Remove the floor panel tunnel brace from the floor panel.
4. Suitably support the exhaust system.
5. Remove the nuts securing the exhaust pipes to the catalytic converters.



6. Pry the front exhaust hangers (1) free from the rear suspension hanger rods.



7. Apply a suitable lubricant to the tail pipe hanger rods in order to ease the removal of the tail pipe hangers (1).
8. Pry the tail pipe hangers (1) free from the tail pipe hanger rods.



9. With the aid of an assistant, lower the exhaust system.
10. Remove the catalytic converter seals. Do not reuse the seals.



11. While the exhaust system is on the floor complete the following:

11.1.

Apply a suitable lubricant to the exhaust pipe hanger rods (3) in order to ease the removal of the front exhaust hangers (2).

11.2.

Pull the front exhaust hangers (2) from the exhaust pipe hanger rods.

1. While the exhaust system is on the floor complete the following:

1.1.	Apply a soapy solution to the following in order to ease the installation of the hangers:

•	The inner diameter of the front exhaust hangers (2)

•	The exhaust pipe hanger rods (3)

•	The inner diameter of the tail pipe hangers

•	The tail pipe hanger rods (1)

1.2.	Press the front exhaust hangers (2) over the exhaust pipe hanger rods (3).

2. Place NEW seals on the catalytic converter flanges.

Notice: Refer to Exhaust System Inspection Notice in the Preface section.

3. With the aid of an assistant, raise the exhaust system into position, aligning the exhaust pipe flanges with the studs located in the rear of the catalytic converters.
4. Finger tighten the nuts to the catalytic converter studs.



5. Press the tail pipe hangers (1) over the tail pipe hanger rods.



6. Press the front exhaust hangers (1) over the rear suspension hanger rods.

Notice: Refer to Fastener Notice in the Preface section.

7. Tighten the exhaust pipes to catalytic converter nuts.

Tighten
Tighten the catalytic converter nuts to 30 N·m (22 lb ft).




8. Position the floor panel tunnel brace to the floor panel.
9. Install the 2 bolts securing the floor panel tunnel brace to the floor panel.

Tighten
Tighten the floor panel tunnel brace bolts to 25 N·m (18 lb ft).

10. Lower the vehicle.