GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 1856626  Size: SH
  1. If equipped with a 6.0L engine, remove the exhaust manifold pipe. Refer to Exhaust Manifold Pipe Replacement.
  2. If equipped with a 6.0L engine, remove the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side.
  3. If equipped with a 6.6L engine, remove the catalytic converter. Refer to Catalytic Converter Replacement.
  4. If equipped with a 4L80-E automatic transmission, regular production option (RPO) MT1, remove the exhaust pipe hanger bracket bolts and bracket.

  5. Object Number: 1856623  Size: SH
  6. If equipped with a Allison® automatic transmission, RPO MW7, remove the exhaust pipe hanger bracket bolt/stud and bracket.

  7. Object Number: 1856629  Size: SH
  8. If equipped with a 6L90-E automatic transmission, RPO MYD, remove the exhaust pipe hanger bracket bolts and bracket.

Installation Procedure

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1856629  Size: SH
  1. If equipped with a 6L90-E automatic transmission, RPO MYD, install the exhaust pipe hanger bracket and bolts and tighten to 25 N·m (18 lb ft).

  2. Object Number: 1856623  Size: SH
  3. If equipped with a Allison® automatic transmission, RPO MW7, install the exhaust pipe hanger bracket and bolt/stud and tighten to 25 N·m (18 lb ft).

  4. Object Number: 1856626  Size: SH
  5. If equipped with a 4L80-E automatic transmission, RPO MT1, install the exhaust pipe hanger bracket and bolts and tighten to 25 N·m (18 lb ft).
  6. If equipped with a 6.6L engine, install the catalytic converter. Refer to Catalytic Converter Replacement.
  7. If equipped with a 6.0L engine, install the left catalytic converter. Refer to Catalytic Converter Replacement - Left Side.
  8. If equipped with a 6.0L engine, install the exhaust manifold pipe. Refer to Exhaust Manifold Pipe Replacement.