GM Service Manual Online
For 1990-2009 cars only

Exhaust Pressure Differential Sensor Pipe Replacement Pickup

Removal Procedure

Caution: The exhaust temperature sensor and exhaust pressure differential sensor line fittings may be difficult to remove when the engine exhaust system temperature is below 48°C (120°F). Excessive force may damage the threads in the exhaust manifold or exhaust pipe.


    Object Number: 1873483  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Reposition the exhaust differential pressure sensor pipe assembly hose clamps (3).
  3. Remove the exhaust differential pressure sensor pipe assembly hoses from the sensor.

  4. Object Number: 1873495  Size: SH
  5. Remove the exhaust differential pressure sensor pipe bracket bolt and nut.

  6. Object Number: 1873498  Size: SH
  7. Loosen the exhaust differential pressure sensor pipe assembly fittings (1).

  8. Object Number: 1873499  Size: SH
  9. Remove the exhaust differential pressure sensor pipe assembly.

Installation Procedure

    Note: A special anti-seize compound is used in the sensor or line fittings threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor or line fitting easier to remove. New, or service replacement sensors or line fittings already have the compound applied to the threads. If the sensor or line fittings are removed from an exhaust component and if for any reason the sensor or line fitting are reinstalled, the threads must have anti-seize compound applied before reinstallation.

  1. If reinstalling the old temperature sensor or differential pressor sensor line fittings, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.

  2. Object Number: 1873499  Size: SH

    Note: Ensure to route the pipe assembly over the frame crossmember.

  3. Position and install the exhaust differential pressure sensor pipe assembly to the vehicle.
  4. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1873498  Size: SH
  5. Tighten the exhaust differential pressure sensor pipe assembly fittings (1).
  6. Tighten
    Tighten the fittings to 45 N·m (33 lb ft).


    Object Number: 1873495  Size: SH
  7. Position the exhaust differential pressure sensor pipe bracket to the exhaust hanger and install the bolt and nut.
  8. Tighten
    Tighten the bracket bolt/nut to 9 N·m (80 lb in).


    Object Number: 1873483  Size: SH
  9. Install the exhaust differential pressure sensor pipe assembly hoses to the sensor.
  10. Position the exhaust differential pressure sensor pipe assembly hose clamps (3).
  11. Lower the vehicle.

Exhaust Pressure Differential Sensor Pipe Replacement Cab/Chassis

Removal Procedure

Caution: The exhaust temperature sensor and exhaust pressure differential sensor line fittings may be difficult to remove when the engine exhaust system temperature is below 48°C (120°F). Excessive force may damage the threads in the exhaust manifold or exhaust pipe.


    Object Number: 1873483  Size: SH
  1. Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle.
  2. Reposition the exhaust differential pressure sensor pipe assembly hose clamps (3).
  3. Remove the exhaust differential pressure sensor pipe assembly hoses from the sensor.

  4. Object Number: 1873495  Size: SH
  5. Remove the exhaust differential pressure sensor pipe bracket bolt and nut.

  6. Object Number: 1873498  Size: SH
  7. Loosen the exhaust differential pressure sensor pipe assembly fittings (1).

  8. Object Number: 1873499  Size: SH
  9. Remove the exhaust differential pressure sensor pipe assembly.

Installation Procedure

    Note: A special anti-seize compound is used in the sensor or line fittings threads. The compound consists of liquid graphite and glass beads. The graphite tends to burn away, but the glass beads remain, making the sensor or line fitting easier to remove. New, or service replacement sensors or line fittings already have the compound applied to the threads. If the sensor or line fittings are removed from an exhaust component and if for any reason the sensor or line fitting are reinstalled, the threads must have anti-seize compound applied before reinstallation.

  1. If reinstalling the old temperature sensor or differential pressor sensor line fittings, coat the threads with anti-seize compound GM P/N 12377953, or equivalent.

  2. Object Number: 1873499  Size: SH

    Note: Ensure to route the pipe assembly over the frame crossmember.

  3. Position and install the exhaust differential pressure sensor pipe assembly to the vehicle.
  4. Caution: Refer to Fastener Caution in the Preface section.


    Object Number: 1873498  Size: SH
  5. Tighten the exhaust differential pressure sensor pipe assembly fittings (1).
  6. Tighten
    Tighten the fittings to 45 N·m (33 lb ft).


    Object Number: 1873495  Size: SH
  7. Position the exhaust differential pressure sensor pipe bracket to the exhaust hanger and install the bolt and nut.
  8. Tighten
    Tighten the bracket bolt/nut to 9 N·m (80 lb in).


    Object Number: 1873483  Size: SH
  9. Install the exhaust differential pressure sensor pipe assembly hoses to the sensor.
  10. Position the exhaust differential pressure sensor pipe assembly hose clamps (3).
  11. Lower the vehicle.