GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2002 🢒 Avalanche - 4WD 🢒 Engine 🢒 Engine Exhaust 🢒 Exhaust Seal Replacement

Removal Procedure

    Object Number: 349061 Size: SH
  1. Raise and suitably support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  2. Remove the engine shield bolts and shield, if necessary.

    3. Object Number: 339429 Size: SH
  3. Remove the oil pan skid plate bolts and plate, if necessary.

    4. Object Number: 665040 Size: SH
  4. Disconnect the CPA retainer.
  5. Disconnect the oxygen sensor electrical connector (1).
  6. Support the catalytic converter or exhaust manifold pipe with adjustable jackstands.

    7. Object Number: 664826 Size: SH
  7. Remove the right exhaust manifold pipe nuts.

    8. Object Number: 309165 Size: SH
  8. Remove the left exhaust manifold pipe nuts.
  9. Remove the exhaust hanger mounting bracket bolts.
  10. Lower the catalytic converter or exhaust manifold pipe using the adjustable jackstands.
  11. Remove the exhaust manifold pipe seal(s).

Installation Procedure

    Object Number: 309165 Size: SH
  1. Install the exhaust manifold pipe seal(s).
  2. Raise the catalytic converter or exhaust manifold pipe using the adjustable jackstands.
  3. Install the exhaust hanger mounting bracket bolts.

    4. 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.

  4. Install the left exhaust manifold pipe nuts.

    5. Tighten

        • Tighten the transmission bolts to 100 N·m (74 lb ft).
        • Tighten the exhaust pipe hanger bracket bolts to 12 N·m (106 lb in).
        • Tighten the exhaust manifold pipe nuts to 50 N·m (39 lb ft).

    Object Number: 664826 Size: SH
  5. Install the right exhaust manifold pipe nuts.

    6. Tighten
    Tighten the nuts to 50 N·m (39 lb ft).


    Object Number: 665040 Size: SH
  6. Connect the oxygen sensor electrical connector (1).
  7. Connect the CPA retainer.
  8. Remove the adjustable jackstands from catalytic converter or exhaust manifold pipe.

    9. Object Number: 339429 Size: SH
  9. Install the oil pan skid plate and bolts, if necessary.

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


    Object Number: 349061 Size: SH
  10. Install the engine shield and bolts, if necessary.

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

  11. Lower the vehicle.