GM Service Manual Online
For 1990-2009 cars only

Muffler 4.3L w/ Intermediate Pipe

Removal Procedure

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

  2. Object Number: 74162  Size: SH
  3. Remove the exhaust muffler clamp.
  4. Remove the resonator rods from the insulators.

  5. Object Number: 72928  Size: SH
  6. Remove the resonator from the muffler.
  7. Important: Ensure that the resonator pipe does not hang on the axle. Otherwise, the brake line on the axle may be damaged.

  8. Support the resonator.

  9. Object Number: 72925  Size: SH
  10. Remove the exhaust muffler bolts.

  11. Object Number: 72932  Size: SH
  12. Remove the muffler rods from the insulators.

  13. Object Number: 73005  Size: SH
  14. Remove the muffler with the intermediate pipe.

Installation Procedure


    Object Number: 73005  Size: SH
  1. Install the muffler with the intermediate pipe.

  2. Object Number: 72932  Size: SH
  3. Install the muffler rods into the insulators.
  4. Loosely install the exhaust muffler bolts.

  5. Object Number: 72928  Size: SH
  6. Install the resonator into the muffler.
  7. Slide the resonator pipe into the muffler outlet, until the tab on the resonator contacts the bottom of the slot, located on top of the muffler outlet.
  8. Install the resonator rods into the insulators.

  9. Object Number: 74162  Size: SH
  10. Install the clamp.
  11. • Assemble the clamp around the resonator pipe.
    • Loosely install the nuts.
    • Tap the clamp toward the rear of the vehicle, in order to contact the tab on the resonator.

    Tighten

       • 

    Tighten the exhaust muffler bolts to 20 N·m (15 lb ft).

       • 

    Tighten the clamp nuts to 35 N·m (26 lb ft).

    •  Refer to

    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.

    in General Information.
  12. Lower the vehicle.

Muffler 5.7L w/ Intermediate Pipe

Removal Procedure

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

  2. Object Number: 72946  Size: SH
  3. Remove the exhaust muffler clamps.
  4. Remove the resonator rods from the insulators.

  5. Object Number: 72928  Size: SH
  6. Remove the resonators from the mufflers.
  7. Important: Ensure that the resonator pipes do not hang on the axle. Otherwise, the brake line on the axle may be damaged.


    Object Number: 72925  Size: SH
  8. Support the exhaust resonators.
  9. Remove the exhaust muffler bolts.

  10. Object Number: 72932  Size: SH
  11. Remove the muffler rods from the insulators.

  12. Object Number: 72949  Size: SH
  13. Remove the mufflers, with the intermediate pipes.

Installation Procedure


    Object Number: 72949  Size: SH
  1. Install the mufflers with the intermediate pipes.

  2. Object Number: 72932  Size: SH
  3. Install the muffler rods into the insulators.

  4. Object Number: 72928  Size: SH
  5. Loosely install the exhaust muffler bolts.
  6. Install the resonators into the mufflers.
  7. Slide the resonator pipes into the muffler outlets, until the tabs on the resonators contact the bottom slots, located on top of the muffler outlets.

  8. Object Number: 72947  Size: SH
  9. Install the resonator rods into the insulators.

  10. Object Number: 72946  Size: SH
  11. Install the clamps.
  12. • Assemble the clamps around the resonator pipes and loosely install the nuts.
    • Tap the clamps toward the rear of the vehicle, in order to contact the tabs on the resonators.

    Tighten

       • 

    Tighten the exhaust muffler bolts to 20 N·m (15 lb ft).

       • 

    Tighten the clamp nuts to 35 N·m (26  lb ft).

    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.

  13. Lower the vehicle.