GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 Sierra - 4WD 🢒 Engine 🢒 Engine Exhaust 🢒 Exhaust Manifold Pipe Replacement

Removal Procedure

    Object Number: 647997 Size: SH
  1. Remove the heated oxygen sensor (HO2S). Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1.
  2. Support the transmission with a suitable transmission jack.
  3. Remove the transmission mount to transmission support nuts.
  4. Using the transmission jack, raise the transmission up off of the transmission support.

    5. Object Number: 1856226 Size: SH
  5. Remove the transmission support crossmember bolts.
  6. Remove the transmission support crossmember.

    7. Object Number: 1856230 Size: SH
  7. Remove the exhaust muffler to exhaust manifold pipe nuts (1).

    8. Object Number: 1856228 Size: SH
  8. Remove the exhaust manifold pipe to exhaust manifold nuts.
  9. Using the transmission jack, lower the transmission slightly.
  10. Separate any necessary exhaust muffler insulators so that the pipe may be separated from the muffler.

    11. Object Number: 1856232 Size: SH
  11. Remove the exhaust manifold pipe.
  12. Discard the exhaust manifold pipe gasket.

Installation Procedure

    Object Number: 1856232 Size: SH
  1. Install a NEW exhaust manifold pipe gasket onto the muffler studs.
  2. Install the exhaust manifold pipe.

    3. Object Number: 1856228 Size: SH
  3. Install any necessary exhaust muffler insulators that were separated from the muffler.
  4. Using the transmission jack, raise the transmission slightly.

    5. Caution: Refer to Fastener Caution in the Preface section.

  5. Install the exhaust manifold pipe to exhaust manifold nuts and tighten to 50 N·m (37 lb ft).

    6. Object Number: 1856230 Size: SH
  6. Install the exhaust muffler to exhaust manifold pipe nuts (1) and tighten to 45 N·m (33 lb ft).

    7. Object Number: 1856226 Size: SH
  7. Position the transmission support crossmember.
  8. Install the transmission support crossmember bolts and tighten to 95 N·m (70 lb ft).

    9. Object Number: 647997 Size: SH
  9. Using the transmission jack, lower the transmission onto the transmission support.
  10. Install the transmission mount to transmission support nuts and tighten to 40 N·m (30 lb ft).
  11. Remove the support from the transmission.
  12. Install the HO2S. Refer to Heated Oxygen Sensor Replacement - Bank 2 Sensor 1.