GM Service Manual Online
For 1990-2009 cars only

    Object Number: 309719  Size: SH

    Important: Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may effect vehicle emissions and/or On-Board Diagnostic (OBD) II system performance.

    The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.

  1. Apply a 5 mm (0.20 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488) or equivalent to the threads of the exhaust manifold bolts.
  2. Refer to Sealers, Adhesives, and Lubricants .

  3. Install the exhaust manifold gasket and exhaust manifold.
  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.

  5. Install the exhaust manifold bolts.
  6. Tighten

    1. Tighten the exhaust manifold bolts first pass to 15 N·m (12 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
    2. Tighten the exhaust manifold bolts final pass to 25 N·m (18 lb ft). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
  7. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the front of the right cylinder head.

  8. Object Number: 1424494  Size: SH
  9. Install the heat shield (603) and bolts (604).
  10. Tighten
    Tighten the heat shield bolts to 9 N·m (80 lb in).