Muffler: Service and Repair
Exhaust Muffler Replacement (L96)
Special Tools
J 38185 - Hose Clamp Pliers
Removal Procedure
Warning: Refer to Exhaust Service Warning Service Precautions.
1. Remove the right rear wheel and tire. Refer to Tire and Wheel Removal and Installation Removal and Replacement.
2. Disconnect the chassis wiring harness electrical connector (1) from the right rear wheel speed sensor wiring harness electrical connector (2).
3. If the vehicle is equipped with regular production option (RPO) Z55, disconnect the chassis wiring harness electrical connector (3) from the right rear shock absorber.
4. If the vehicle is equipped with RPO Z55, disconnect the right rear air line from the shock absorber.
5. Remove the right rear wheel speed sensor wiring harness electrical connector clip from the frame.
Note: The rear axle wiring harness clip is a one way clip with a D-shape section. The clip can only be installed and/or removed in only one direction.
6. Remove the right rear wheel speed sensor wiring harness clips from the frame and the control arm bracket.
Note: Do not attempt to pry the rear suspension sensor link rod from the rear position sensor ball stud.
7. Disconnect the right rear automatic level control sensor link rod from the sensor. Perform the following:
1. Support the sensor lever with your hand.
2. Twist the link rod ball in order to separate it from the ball stud.
8. Install a suitable adjustable jack under the rear axle.
9. Remove the right axle tie rod bolt (2) and nut (1).
10. Remove the rear axle vent hose from the rear axle, if necessary.
11. Remove the vent hose swivel clip from the rear brake crossover pipe, if necessary.
12. Remove the right rear stabilizer shaft link to frame bolt and nut.
13. Remove the right rear stabilizer shaft link from the frame.
14. Remove the right rear shock absorber lower bolt (4) and nut (3).
15. Lower the right side of the rear axle using the adjustable jack in order to remove the muffler.
16. Loosen the catalytic converter to muffler clamp nut (1).
17. Separate the hanger.
18. If the vehicle is a Yukon Denali or Escalade, perform the following steps, otherwise proceed to step 23.
19. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
20. With the aid of an assistant, remove the insulators from the exhaust system hangers (4 and 5).
21. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
22. Remove the muffler assembly.
23. If the vehicle is a Yukon XL, Yukon Denali XL, Escalade ESV, or Escalade EXT perform the following steps:
* Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
* With the aid of an assistant, remove the insulators from the exhaust system hangers (3, 4, and 5).
24. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
Note: During removal, do not over extend the flex coupler as internal damage may occur.
25. Remove the muffler assembly.
Installation Procedure
1. If the vehicle is a Yukon XL, Yukon Denali XL, Escalade ESV, or Escalade EXT perform the following steps, otherwise proceed to step 6.
2. Lubricate the insulators where the muffler assembly hangers are inserted for ease of installation.
Note: During installation, do not over extend the flex coupler as internal damage may occur.
3. With the aid of an assistant, install the muffler assembly.
4. With the aid of an assistant, install the insulators to the exhaust system hangers (3, 4, and 5).
5. With the aid of an assistant, Install the insulator to the exhaust system hanger near the resonator.
6. If the vehicle is a Yukon Denali or Escalade perform the following:
* Lubricate the insulators where the muffler assembly hangers are inserted for ease of installation.
* With the aid of an assistant, install the muffler assembly.
* With the aid of an assistant, install the insulators to the exhaust system hangers (2, and 3).
7. Install the insulator to the exhaust system hanger near the resonator.
Caution: Refer to Fastener Caution Fastener Caution.
8. Position the muffler assembly to the three-way catalytic converter and tighten the norma clamp bolt (1) to 28 Nm (21 lb ft).
9. Install the insulator to the hanger.
10. Raise the rear axle into position using the adjustable jack.
11. Install the right rear shock absorber lower bolt and nut and tighten to 95 Nm (70 lb ft).
12. Install the right rear stabilizer shaft link to the frame.
13. Install the right rear stabilizer shaft link to frame bolt and nut and tighten to 65 Nm (48 lb ft).
14. Install the right rear axle tie rod bolt (2) and nut (1) and tighten to 105 Nm (77 lb ft).
15. Install the rear axle vent hose to the rear axle, if necessary.
16. Install the vent hose swivel clip to the rear brake crossover pipe, if necessary.
17. Using the J 38185 - hose clamp pliers install the right rear link rod to the ball studs on the sensors.
Note: The rear axle wiring harness clip is a one way clip with a D-shape section. The clip can only be installed and/or removed in only one direction.
18. Install the right rear wheel speed sensor wiring harness clips to the frame and the control arm bracket.
19. Install the right rear wheel speed sensor wiring harness electrical connector clip to the frame.
20. If the vehicle is equipped with RPO Z55, connect the right rear air line to the shock absorber.
21. If the vehicle is equipped with RPO Z55, connect the chassis wiring harness electrical connector (3) to the right rear shock absorber.
22. Connect the chassis wiring harness electrical connector (1) to the right rear wheel speed sensor wiring harness electrical connector (2).
23. Install the right rear wheel and tire. Refer to Tire and Wheel Removal and Installation Removal and Replacement.