GM Service Manual Online
For 1990-2009 cars only

Removal Procedure


    Object Number: 715660  Size: SH
  1. Remove the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement .
  2. Remove the front propeller shaft. Refer to Front Propeller Shaft Replacement in Propeller Shaft.
  3. Disconnect the encoder motor electrical connector.

  4. Object Number: 857301  Size: SH
  5. Remove the encoder motor bolts.
  6. Remove the encoder motor.
  7. Remove the actuator insulator gasket.
  8. If replacing the encoder motor, remove the locating pins from the old motor.

Installation Procedure

Important: 

   • If the encoder motor is being replaced because it is defective, ensure that the transfer case is in the neutral position. Manually shift the unit at the shift shaft. Use a crescent wrench, if necessary.
   • If the encoder motor is being replaced, a new gasket will come with the encoder motor. DO NOT reuse the old gasket.
   • A NEW encoder motor does NOT come with locating pins.


    Object Number: 857328  Size: SH
  1. Install the locating pins to the NEW encoder motor.
  2. Position a NEW actuator insulator gasket to the transfer case.
  3. Install the encoder motor.
  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 encoder motor bolts.
  6. Tighten
    Tighten the bolts, in the sequence shown, to 20 N·m (15 lb ft).


    Object Number: 715660  Size: SH
  7. Connect the encoder motor electrical connector. Ensure that the retention clips activate.
  8. Install the front propeller shaft. Refer to Front Propeller Shaft Replacement in Propeller Shaft.
  9. Install the transfer case shield, if equipped. Refer to Transfer Case Shield Replacement .