GM Service Manual Online
For 1990-2009 cars only

    Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1401959  Size: SH

    Note: 

       â€¢ Tighten the exhaust manifold bolts as specified in the service procedure. Improperly installed and/or leaking exhaust manifold gaskets may affect vehicle emissions and/or on-board diagnostic (OBD) II system performance.
       â€¢ The cylinder head exhaust manifold bolt hole threads must be clean and free of debris or threadlocking material.
       â€¢ Do not apply sealant to the first 3 threads of the bolt.

  1. Install the heat shield (603) and bolts (604). Tighten the heat shield bolts to 9 N·m (80 lb in).
  2. Install the exhaust pipe studs (605) and tighten to 20 N·m (15 lb ft).

  3. Object Number: 1401957  Size: SH
  4. Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 (Canadian P/N 10953488), or equivalent, to the threads of the exhaust manifold bolts. Refer to Adhesives, Fluids, Lubricants, and Sealers.
  5. Install the exhaust manifold, NEW gasket, and bolts.
  6. 4.1. Tighten the exhaust manifold bolts a first pass to 15 N·m (11 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 bolts. Alternate from side-to-side, and work toward the outside bolts.
    4.2. Tighten the exhaust manifold bolts a final pass to 20 N·m (15 lb ft). Tighten the exhaust manifold bolts beginning with the center 2 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 rear of the left cylinder head.