GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1998 🢒 DeVille 🢒 Engine 🢒 Engine Exhaust 🢒 Exhaust Manifold Replacement

Removal Procedure
  1. Remove the torque struts.
  2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
  3. Remove the pinch bolt from the steering racket. Refer to Steering Gear Replacement in Steering.
  4. Remove the level control. Refer to Automatic Level Control Sensor and Bracket Replacement in Suspension.

    5. Object Number: 72022 Size: SH
  5. Remove the four nuts from the converter flange.
  6. Lower the frame.

    7. Notice: Lower the frame approximately 1 inch. Lowering the cradle too far may cause damage to the engine electrical connections and wiring.


    Object Number: 72023 Size: SH
  7. Remove the four 15 mm bolts from the catalytic converter.
  8. Remove the two 15 mm bolts from the exhaust manifold.
  9. Remove the two 10 mm bolts from the crossover pipe.
  10. Remove the exhaust manifold rear pipe from the vehicle.

Installation Procedure

    Object Number: 72022 Size: SH
  1. Install the two 15 mm bolts from the exhaust manifold.

    2. Tighten
    Tighten the exhaust manifold flange bolts to 40 N·m (30 lb ft).

    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.

  2. Install the two 10 mm bolts from the crossover pipe.

    3. Tighten
    Tighten the crossover pipe bolts to 40 N·m (30 lb ft).


    Object Number: 71698 Size: SH
  3. Raise the engine frame.

    4. Tighten
    Tighten the cradle bolts to 192 N·m (142 lb ft).

  4. Install the converter seal.
  5. Install the converter nuts.

    6. Tighten
    Tighten the converter nuts to 24 N·m (18 lb ft).

  6. Install the level control. Refer to Automatic Level Control Sensor and Bracket Replacement in Suspension.
  7. Install the pinch bolt. Refer to Steering Gear Replacement in Steering.
  8. Lower the vehicle.
  9. Install the torque struts.