GM Service Manual Online
For 1990-2009 cars only

Removal Procedure

Caution: In order to avoid being burned, do not service the exhaust system while it is still hot. Service the system when it is cool.

Caution: Always wear protective goggles and gloves when removing exhaust parts as falling rust and sharp edges from worn exhaust components could result in serious personal injury.

  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.

  2. Object Number: 71703  Size: SH
  3. Remove the 4 nuts securing the catalytic converter to the exhaust manifold rear pipe.
  4. Notice: Do not over-flex or damage the flex joint when moving the flex joint from the normal mounting position.

  5. Position the exhaust system rearward, enough to allow the studs located in the front of the catalytic converter to clear the exhaust manifold rear pipe.
  6. Remove the catalytic converter gasket. Do not reuse the gasket.

  7. Object Number: 691444  Size: SH
  8. Remove the 2 bolts (2) attaching the exhaust manifold rear pipe to the right exhaust manifold.
  9. Remove the 2 bolts (3) securing the exhaust manifold rear pipe to the exhaust manifold front pipe.
  10. Remove the exhaust manifold rear pipe and the gasket (1). Do not reuse the gasket.
  11. Remove the exhaust manifold pipe seal (4) from the exhaust manifold front pipe. Do not reuse the seal.
  12. Remove the exhaust manifold flange seal retainer (5).

Installation Procedure


    Object Number: 691444  Size: SH

    Notice: When inspecting or replacing exhaust system components, make sure there is adequate clearance from all points on the underbody to prevent overheating of the floor pan and possible damage to the passenger compartment insulation and trim materials.

  1. Install the following components to the exhaust manifold rear pipe:
  2. 1.1. Position a NEW exhaust manifold pipe seal (4) and the exhaust manifold flange seal retainer (5) to the exhaust manifold rear pipe flange.
    1.2. Insert the 2 retaining bolts (3) through the exhaust manifold rear pipe flange and into the exhaust manifold flange seal retainer (5).
    1.3. Finger tighten the 2 retaining bolts (3) in order to retain the pipe seal (4) and retainer (5).
    1.4. Position a NEW gasket (1) to the exhaust manifold rear pipe flange.
    1.5. Insert the 2 retaining bolts (2) through the exhaust manifold rear pipe flange and into the gasket (1).
  3. Insert the exhaust manifold rear pipe around the exhaust manifold front pipe and up to the right 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 2 bolts (2) attaching the exhaust manifold rear pipe to the right exhaust manifold.
  6. Tighten

    1. Tighten the 2 right exhaust manifold rear pipe to right exhaust manifold bolts to 40 N·m (30 lb ft).
    2. Tighten the 2 left exhaust manifold rear pipe to exhaust manifold flange seal retainer bolts to 25 N·m (18 lb ft).

    Object Number: 71703  Size: SH
  7. Place a NEW catalytic converter gasket over the catalytic converter studs.
  8. Notice: Do not over-flex or damage the flex joint when moving the flex joint from the normal mounting position.

  9. Position the catalytic converter to the exhaust manifold rear pipe.
  10. Install the 4 nuts in order to secure the catalytic converter to the exhaust manifold rear pipe.
  11. Tighten
    Tighten the catalytic converter nuts to 25 N·m (18 lb ft).

  12. Lower the vehicle.