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For 1990-2009 cars only

Exhaust Muffler Replacement 1500 - LMG/LY2/LY5

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure


    Object Number: 1709051  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  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.

  6. Object Number: 1709061  Size: SH

    Important: 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.

  7. Remove the right rear wheel speed sensor wiring harness clips from the frame and the control arm bracket.
  8. Important: Do not attempt to pry the rear suspension sensor link rod from the rear position sensor ball stud.

  9. Disconnect the right rear automatic level control sensor link rod from the sensor. Perform the following:
  10. 7.1. Support the sensor lever with your hand.
    7.2. Twist the link rod ball in order to separate it from the ball stud.
  11. Install a suitable adjustable jack under the rear axle.
  12. Remove the right axle tie rod bolt (2) and nut (1).

  13. Object Number: 692548  Size: SH
  14. Remove the rear axle vent hose from the rear axle, if necessary.
  15. Remove the vent hose swivel clip from the rear brake crossover pipe, if necessary.
  16. Remove the right rear stabilizer shaft link to frame bolt and nut.
  17. Remove the right rear stabilizer shaft link from the frame.
  18. Remove the right rear shock absorber lower bolt and nut.
  19. Lower the right side of the rear axle using the adjustable jack in order to remove the muffler.

  20. Object Number: 1708705  Size: SH
  21. Remove the catalytic converter to muffler nuts.

  22. Object Number: 1708981  Size: SH
  23. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
  24. With the aid of an assistant, remove the insulators from the exhaust system hangers (2 and 3).

  25. Object Number: 1708983  Size: SH
  26. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
  27. Important: During removal, do not over extend the flex coupler as internal damage may occur.

  28. Remove the muffler assembly.

Installation Procedure


    Object Number: 1708981  Size: SH
  1. Lubricate the insulators where the muffler assembly hangers are inserted for ease of installation.
  2. Notice: To prevent internal damage to the flexible coupling of the catalytic converter assembly, the converter must be supported. The vertical movement at the rear of the catalytic converter assembly must not exceed 6 degrees up or down.

  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 (2 and 3).

  5. Object Number: 1708983  Size: SH
  6. Install the insulator to the exhaust system hanger near the resonator.
  7. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1708705  Size: SH
  8. Install the catalytic converter to muffler nuts.
  9. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  10. Raise the right side of the rear axle into position using the adjustable jack.

  11. Object Number: 1709061  Size: SH
  12. Install the right rear shock absorber lower bolt and nut.
  13. Tighten
    Tighten the bolt/nut to 95 N·m (70 lb ft).

  14. Install the right rear stabilizer shaft link to the frame.
  15. Install the right rear stabilizer shaft link to frame bolt and nut.
  16. Tighten
    Tighten the bolt/nut to 65 N·m (48 lb ft).

  17. Install the right rear axle tie rod bolt (2) and nut (1).
  18. Tighten
    Tighten the bolt/nut to 105 N·m (77 lb ft).


    Object Number: 692548  Size: SH
  19. Install the rear axle vent hose to the rear axle, if necessary.
  20. Install the vent hose swivel clip to the rear brake crossover pipe, if necessary.
  21. Using the J 38185 install the right rear link rod to the ball studs on the sensors.
  22. Important: 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.

  23. Install the right rear wheel speed sensor wiring harness clips to the frame and the control arm bracket.
  24. Install the right rear wheel speed sensor wiring harness electrical connector clip to the frame.

  25. Object Number: 1709051  Size: SH
  26. If the vehicle is equipped with RPO Z55, connect the right rear air line to the shock absorber.
  27. If the vehicle is equipped with RPO Z55, connect the chassis wiring harness electrical connector (3) to the right rear shock absorber.
  28. Connect the chassis wiring harness electrical connector (1) to the right rear wheel speed sensor wiring harness electrical connector (2).
  29. Lower the vehicle.

Exhaust Muffler Replacement 1500 - L92

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure


    Object Number: 1709051  Size: SH
  1. Remove the right rear wheel and tire. Refer to Tire and Wheel Removal and Installation .
  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.

  6. Object Number: 1709061  Size: SH

    Important: 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.

  7. Remove the right rear wheel speed sensor wiring harness clips from the frame and the control arm bracket.
  8. Important: Do not attempt to pry the rear suspension sensor link rod from the rear position sensor ball stud.

  9. Disconnect the right rear automatic level control sensor link rod from the sensor. Perform the following:
  10. 7.1. Support the sensor lever with your hand.
    7.2. Twist the link rod ball in order to separate it from the ball stud.
  11. Install a suitable adjustable jack under the rear axle.
  12. Remove the right axle tie rod bolt (2) and nut (1).

  13. Object Number: 692548  Size: SH
  14. Remove the rear axle vent hose from the rear axle, if necessary.
  15. Remove the vent hose swivel clip from the rear brake crossover pipe, if necessary.
  16. Remove the right rear stabilizer shaft link to frame bolt and nut.
  17. Remove the right rear stabilizer shaft link from the frame.
  18. Remove the right rear shock absorber lower bolt (4) and nut (3).
  19. Lower the right side of the rear axle using the adjustable jack in order to remove the muffler.

  20. Object Number: 1708979  Size: SH
  21. Remove the muffler to catalytic converter nuts.
  22. Separate the hanger.

  23. Object Number: 1708984  Size: SH
  24. If the vehicle is a Yukon Denali or Escalade perform the following steps, otherwise proceed to step 26.
  25. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
  26. With the aid of an assistant, remove the insulators from the exhaust system hangers (4, and 5).

  27. Object Number: 1708985  Size: SH
  28. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
  29. Remove the muffler assembly.

  30. Object Number: 1708986  Size: SH
  31. If the vehicle is a Yukon XL, Yukon Denali XL, Escalade ESV, or Escalade EXT perform the following steps.
  32. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
  33. With the aid of an assistant, remove the insulators from the exhaust system hangers (3, 4, and 5).

  34. Object Number: 1708987  Size: SH
  35. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
  36. Important: During removal, do not over extend the flex coupler as internal damage may occur.

  37. Remove the muffler assembly.

Installation Procedure


    Object Number: 1708986  Size: SH
  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.
  3. Important: During installation, do not over extend the flex coupler as internal damage may occur.

  4. With the aid of an assistant, install the muffler assembly.
  5. With the aid of an assistant, install the insulators to the exhaust system hangers (3, 4, and 5).

  6. Object Number: 1708987  Size: SH
  7. With the aid of an assistant, Install the insulator to the exhaust system hanger near the resonator.

  8. Object Number: 1708981  Size: SH
  9. If the vehicle is a Yukon Denali or Escalade perform the following.
  10. Lubricate the insulators where the muffler assembly hangers are inserted for ease of installation.
  11. With the aid of an assistant, install the muffler assembly.
  12. With the aid of an assistant, install the insulators to the exhaust system hangers (2, and 3).

  13. Object Number: 1708983  Size: SH
  14. Install the insulator to the exhaust system hanger near the resonator.
  15. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1708979  Size: SH
  16. Install the muffler to catalytic converter nuts.
  17. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  18. Install the insulator to the hanger.
  19. Raise the rear axle into position using the adjustable jack.

  20. Object Number: 1709061  Size: SH
  21. Install the right rear shock absorber lower bolt and nut.
  22. Tighten
    Tighten the bolt/nut to 95 N·m (70 lb ft).

  23. Install the right rear stabilizer shaft link to the frame.
  24. Install the right rear stabilizer shaft link to frame bolt and nut.
  25. Tighten
    Tighten the bolt/nut to 65 N·m (48 lb ft).

  26. Install the right rear axle tie rod bolt (2) and nut (1).
  27. Tighten
    Tighten the bolt/nut to 105 N·m (77 lb ft).


    Object Number: 692548  Size: SH
  28. Install the rear axle vent hose to the rear axle, if necessary.
  29. Install the vent hose swivel clip to the rear brake crossover pipe, if necessary.
  30. Using the J 38185 install the right rear link rod to the ball studs on the sensors.
  31. Important: The rear axle wiring harness clip (1) is a one way clip with a D-shape section. The clip can only be installed and/or removed in only one direction.

  32. Install the right rear wheel speed sensor wiring harness clips to the frame and the control arm bracket.
  33. Install the right rear wheel speed sensor wiring harness electrical connector clip to the frame.

  34. Object Number: 1709051  Size: SH
  35. If the vehicle is equipped with RPO Z55, connect the right rear air line to the shock absorber.
  36. If the vehicle is equipped with RPO Z55, connect the chassis wiring harness electrical connector (3) to the right rear shock absorber.
  37. Connect the chassis wiring harness electrical connector (1) to the right rear wheel speed sensor wiring harness electrical connector (2).
  38. Install the right rear wheel and tire. Refer to Tire and Wheel Removal and Installation .

Exhaust Muffler Replacement 2500

Removal Procedure


    Object Number: 1708726  Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle .
  2. Remove the exhaust muffler to right catalytic converter nuts.
  3. Loosen the exhaust pipe clamp at the left catalytic converter.

  4. Object Number: 1708988  Size: SH
  5. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
  6. With the aid of an assistant, remove the insulators from the exhaust system hangers (4, 5, and 6).
  7. Pull the muffler assembly rearward in order to separate the muffler from the catalytic converters. Once the muffler is separated from the converters, move and rotate the muffler towards the front of the vehicle, removing the muffler from the vehicle.

Installation Procedure


    Object Number: 1708988  Size: SH
  1. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease installation.
  2. With the aid of an assistant, install the muffler assembly. Rotate the muffler into position over the rear axle, move the muffler rearward, then forward installing the muffler to the catalytic converters.
  3. Install the insulators to the exhaust system hangers (4, 5, and 6).
  4. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1708726  Size: SH
  5. Tighten the exhaust pipe clamp at the left catalytic converter.
  6. Tighten
    Tighten the clamp to 44 N·m (32 lb ft).

  7. Install the exhaust muffler to right catalytic converter nuts.
  8. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  9. Lower the vehicle.

Exhaust Muffler Replacement 1500 - LC9/LMG/LY5/L76

Tools Required

J 38185 Hose Clamp Pliers

Removal Procedure


    Object Number: 1709051  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle .
  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.

  6. Object Number: 1709061  Size: SH

    Important: 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.

  7. Remove the right rear wheel speed sensor wiring harness clips from the frame and the control arm bracket.
  8. Important: Do not attempt to pry the rear suspension sensor link rod from the rear position sensor ball stud.

  9. Disconnect the right rear automatic level control sensor link rod from the sensor. Perform the following:
  10. 7.1. Support the sensor lever with your hand.
    7.2. Twist the link rod ball in order to separate it from the ball stud.
  11. Install a suitable adjustable jack under the rear axle.
  12. Remove the right axle tie rod bolt (2) and nut (1).

  13. Object Number: 692548  Size: SH
  14. Remove the rear axle vent hose from the rear axle, if necessary.
  15. Remove the vent hose swivel clip from the rear brake crossover pipe, if necessary.
  16. Remove the right rear stabilizer shaft link to frame bolt and nut.
  17. Remove the right rear stabilizer shaft link from the frame.
  18. Remove the right rear shock absorber lower bolt (4) and nut (3).
  19. Lower the right side of the rear axle using the adjustable jack in order to remove the muffler.

  20. Object Number: 1708705  Size: SH
  21. Remove the catalytic converter to muffler nuts.

  22. Object Number: 1709380  Size: SH
  23. Lubricate the insulators where the muffler assembly hangers are inserted in order to ease in removal.
  24. With the aid of an assistant, remove the insulators from the exhaust system hangers (1, 2, and 3).

  25. Object Number: 1709383  Size: SH
  26. With the aid of an assistant, remove the insulator from the exhaust system hanger near the resonator.
  27. Important: During removal, do not over extend the flex coupler as internal damage may occur.

  28. Remove the muffler assembly.

Installation Procedure


    Object Number: 1709380  Size: SH
  1. Lubricate the insulators where the muffler assembly hangers are inserted for ease of installation.
  2. Important: 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 (1, 2, and 3).

  5. Object Number: 1709383  Size: SH
  6. Install the insulator to the exhaust system hanger near the resonator.
  7. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1708705  Size: SH
  8. Install the catalytic converter to muffler nuts.
  9. Tighten
    Tighten the nuts to 45 N·m (33 lb ft).

  10. Raise the rear axle into position using the adjustable jack.

  11. Object Number: 1709061  Size: SH
  12. Install the right rear shock absorber lower bolt and nut.
  13. Tighten
    Tighten the bolt/nut to 95 N·m (70 lb ft).

  14. Install the right rear stabilizer shaft link to the frame.
  15. Install the right rear stabilizer shaft link to frame bolt and nut.
  16. Tighten
    Tighten the bolt/nut to 65 N·m (48 lb ft).

  17. Install the right rear axle tie rod bolt (2) and nut (1).
  18. Tighten
    Tighten the bolt/nut to 105 N·m (77 lb ft).


    Object Number: 692548  Size: SH
  19. Install the rear axle vent hose to the rear axle, if necessary.
  20. Install the vent hose swivel clip to the rear brake crossover pipe, if necessary.
  21. Using the J 38185 install the right rear link rod to the ball studs on the sensors.
  22. Important: 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.

  23. Install the right rear wheel speed sensor wiring harness clips to the frame and the control arm bracket.
  24. Install the right rear wheel speed sensor wiring harness electrical connector clip to the frame.

  25. Object Number: 1709051  Size: SH
  26. If the vehicle is equipped with RPO Z55, connect the right rear air line to the shock absorber.
  27. If the vehicle is equipped with RPO Z55, connect the chassis wiring harness electrical connector (3) to the right rear shock absorber.
  28. Connect the chassis wiring harness electrical connector (1) to the right rear wheel speed sensor wiring harness electrical connector (2).
  29. Lower the vehicle.