Installation Procedure

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 diagnostics (OBD) II system performance.

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

Important:  Do not apply threadlock to the first three threads of the bolts.

1. Apply a 5 mm (0.2 in) wide band of threadlock GM P/N 12345493 or equivalent to the threads of the exhaust manifold bolts.
2. Install a NEW exhaust manifold gasket and the exhaust manifold.
   NOTE: 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.
   Fig 1: Installing New Exhaust Manifold Gasket And Exhaust Manifold

   Courtesy of GENERAL MOTORS CORP.
3. Install the exhaust manifold bolts.

   Tighten 

   1. 3.1. Tighten the exhaust manifold bolts a first pass to 15 N.m (11 ft lbs). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
   2. 3.2. Tighten the exhaust manifold bolts a final pass to 25 N.m (18 ft lbs). Tighten the exhaust manifold bolts beginning with the center two bolts. Alternate from side-to-side, and work toward the outside bolts.
4. Using a flat punch, bend over the exposed edge of the exhaust manifold gasket at the rear of the cylinder head.
5. Install the heat shield (2) and heat shield bolts (3) to the manifold (1), if required.

   Tighten 

   Tighten the heat shield bolts (3) to 9 N.m (80 Inch lbs).

6. Install the right catalytic converter. Refer to CATALYTIC CONVERTER REPLACEMENT - RIGHT (5.7L) .
7. Lower the vehicle.
8. Install the spark plugs.
9. Install the right valve rocker arm cover. Refer to VALVE COVERS .
   Fig 2: Installing Heat Shield And Heat Shield Bolts

   Courtesy of GENERAL MOTORS CORP.