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For 1990-2009 cars only

Exhaust Manifold Replacement - Left Side 8.1L

Removal Procedure


    Object Number: 742280  Size: SH
  1. Remove the oil level indicator tube. Refer to Oil Level Indicator and Tube Replacement in Engine Mechanical - 8.1L.
  2. Raise and suitably support the vehicle with safety stands. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the exhaust manifold pipe nuts.
  4. Remove the exhaust pipe seal.
  5. Allow the muffler pipe to hang.
  6. Lower the vehicle.

  7. Object Number: 470666  Size: SH

    Important: Twist the spark plug boot ½ turn in order to release the boot. Pull on the spark plug boot only. Do not pull on the spark plug wire or the wire could be damaged.

  8. Remove the spark plug wires from the spark plugs and ignition coils.
  9. Remove the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 8.1L.

  10. Object Number: 470678  Size: SH
  11. Remove the exhaust manifold heat shield nuts.
  12. Remove the heat shield.

  13. Object Number: 470686  Size: SH
  14. Remove the exhaust manifold bolt and nuts.
  15. Remove the exhaust manifold and gasket. Discard the gasket.
  16. Clean and inspect the exhaust manifold. Refer to Exhaust Manifold Cleaning and Inspection in Engine Mechanical - 8.1L Unit Repair.

Installation Procedure


    Object Number: 470686  Size: SH
  1. Install a NEW gasket.
  2. Install the exhaust manifold.
  3. 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.

  4. Install the exhaust manifold bolt and nuts.
  5. Tighten

        • Tighten the exhaust manifold bolt to 35 N·m (26 lb ft).
        • Tighten the exhaust manifold nuts to 16 N·m (12 lb ft).

    Object Number: 470678  Size: SH
  6. Install the exhaust manifold heat shield.
  7. Install the exhaust manifold heat shield nuts.
  8. Tighten
    Tighten the exhaust manifold heat shield nuts to 25 N·m (18 lb ft).

  9. Install the spark plugs. Refer to Spark Plug Replacement in Engine Controls - 8.1L.

  10. Object Number: 470666  Size: SH

    Important: Fully install the spark plug wire by pushing on the exposed end of the spark plug boot. Do not push the spark plug wire on the spark plug by using the metal heat shield.

  11. Install the spark plug wires to the spark plugs and ignition coils.

  12. Object Number: 742280  Size: SH
  13. Raise and suitably support the vehicle with safety stands.
  14. Raise the muffler pipe up to the manifold.
  15. Install the exhaust pipe seal.
  16. Install the exhaust manifold pipe nuts.
  17. Tighten
    Tighten the exhaust manifold pipe nuts to 50 N·m (37 lb ft).

  18. Lower the vehicle.

Exhaust Manifold Replacement - Left Side 6.6L

Removal Procedure

  1. Remove the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  2. Remove the air cleaner. Refer to Air Cleaner Replacement in Engine Controls - 6.6L (LLY).
  3. Remove the charged air cooler outlet duct. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  4. Remove the bolt for the oil level indicator tube bracket in order to remove the exhaust manifold gasket.

  5. Object Number: 785649  Size: SH
  6. Remove the exhaust pipe to exhaust manifold bolts (2).

  7. Object Number: 660370  Size: SH
  8. Remove the exhaust manifold bolts/nuts.
  9. Remove the exhaust manifold.
  10. 7.1. Remove the manifold from the rear stud.
    7.2. Remove the manifold from the front stud.
    7.3. Slide the manifold out the bottom, past the oil filter.
  11. Remove and discard the exhaust manifold gasket.

Installation Procedure

  1. Install the exhaust manifold with gasket.
  2. Install the exhaust manifold bolts/nuts.
  3. Notice: Refer to Fastener Notice in the Preface section.


    Object Number: 1872600  Size: SH
  4. Use the sequence shown, to properly tighten the exhaust manifold bolts.
  5. Tighten

    1. Tighten the exhaust manifold bolts/nut a first pass to 34 N·m (25 lb ft).
    2. Tighten the exhaust manifold bolts/nuts a final pass to 34 N·m (25 lb ft).
  6. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.
  7. Install the bolt for the oil level indicator tube bracket.
  8. Tighten
    Tighten the oil level indicator tube bracket bolt to 21 N·m (15 lb ft).


    Object Number: 654524  Size: SH
  9. Install the exhaust pipe gasket. Align the tab on the gasket to face outward.
  10. Install the exhaust pipe and the bolts (2) to the exhaust manifold.
  11. Tighten
    Tighten the exhaust pipe to exhaust manifold bolts to 53 N·m (39 lb ft).

  12. Install the charged air cooler outlet duct. Refer to Charged Air Cooler Hoses/Pipes Replacement in Engine Mechanical - 6.6L (LLY).
  13. Install the air cleaner. Refer to Air Cleaner Replacement in Engine Controls - 6.6L (LLY).
  14. Install the engine cover. Refer to Engine Cover Replacement in Interior Trim.