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For 1990-2009 cars only

Air Brake Automatic Slack Adjuster Replacement Rockwell

Removal Procedure

    Important: For unit repair information on the Rockwell air brake automatic slack adjuster contact the Rockwell Field Support Center at 1-800-535-5560.

  1. Block the wheels.
  2. Cage the rear air brake chambers. Refer to Caging the Rear Air Brake Chamber .
  3. Drain all of the air reservoirs. Refer to Draining Reservoirs in Air Brakes.
  4. Raise the vehicle and support the vehicle with safety stands. Refer to Lifting and Jacking the Vehicle in General Information.

  5. Object Number: 201804  Size: SH
  6. Mark the position of the slack adjuster to the camshaft by drawing a straight line on both components.

  7. Object Number: 201809  Size: SH
  8. Remove the retainers.
  9. Remove the air brake chamber clevis pins.

  10. Object Number: 201765  Size: SH
  11. In order to fully release the air brake automatic slack adjuster, adhere to the following steps:
  12. 8.1. Disengage the pawl with a screwdriver.
    8.2. Turn the slack adjuster adjusting nut until the air brake automatic slack adjuster is free from the air brake chamber clevis.
    8.3. Release the pawl so that the pawl snaps into engagement.

    Object Number: 201813  Size: SH
  13. Remove the camshaft snap ring.

  14. Object Number: 261832  Size: MH
  15. Remove the camshaft washer(s) (5).
  16. Remove the slack adjuster (4).

  17. Object Number: 201816  Size: SH
  18. In order to check the slack adjuster adjusting nut torque, adhere to the following steps:
  19. 12.1. Use a pound inch torque wrench in order to rotate the air brake automatic slack adjuster adjusting nut counterclockwise.
    12.2. Turn the air brake automatic slack adjuster gear 360 degrees (22 rotations of the air brake automatic slack adjuster adjusting nut). The torque must remain less than 4.51 N·m (40 lb in). Overhaul or replace the air brake automatic slack adjuster if the torque specification is exceeded.

    Object Number: 201809  Size: SH
  20. Inspect the air brake chamber clevis pins for wear or damage.
  21. Replace the air brake chamber clevis pins if necessary.


    Object Number: 261832  Size: MH
  22. Measure the bushing in the arm of the slack adjuster (4).
  23. Replace the bushings if the diameter exceeds 13.5 mm (0.531 in).

Installation Procedure


    Object Number: 261832  Size: MH
  1. Install the slack adjuster (4) to the camshaft.
  2. Install the camshaft washer(s) (5).

  3. Object Number: 201813  Size: SH
  4. Install the camshaft snap ring.

  5. Object Number: 201765  Size: SH
  6. Disengage the pawl assembly with a screwdriver.

  7. Object Number: 201817  Size: SH
  8. Turn the slack adjuster adjusting nut until the air brake automatic slack adjuster arm is properly aligned with the holes in the air brake chamber clevis.
  9. Release the pawl so that the pawl snaps into engagement.

  10. Object Number: 201804  Size: SH
  11. Align the marks made on the slack adjuster and the camshaft.
  12. Fully release the slack adjuster.

  13. Object Number: 201809  Size: SH
  14. Install the air brake chamber clevis pins.
  15. 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.

  16. Install the new retainers.
  17. Adjust the brakes. Refer to Air Drum Brake Adjustment .
  18. Remove the safety stands and lower the vehicle.
  19. Uncage the rear air brake chambers. Refer to Caging the Rear Air Brake Chamber .
  20. Check for proper brake operation.
  21. Set the parking brake.
  22. Remove the wheel blocks.

Air Brake Automatic Slack Adjuster Replacement Eaton

Removal Procedure

    Important: The Eaton® air brake automatic slack adjuster is not serviceable. Replace any damaged Eaton air brake automatic slack adjusters.

  1. Block the wheels.
  2. Cage the rear air brake chambers. Refer to Caging the Rear Air Brake Chamber .
  3. Drain all air reservoirs. Refer to Draining Reservoirs in Air Brakes.

  4. Object Number: 201820  Size: SH
  5. Remove the retainer.
  6. Remove the air brake chamber clevis pin cotter pin.
  7. Remove the air brake chamber clevis pin.
  8. Fully release the slack adjuster by turning the slack adjuster counterclockwise until the slack adjuster arm is free from the air brake chamber clevis.

  9. Object Number: 201833  Size: SH
  10. Remove the slack adjuster control arm nut and the washer.

  11. Object Number: 201813  Size: SH
  12. Remove the camshaft snap ring.

  13. Object Number: 261832  Size: MH
  14. Remove the camshaft washer(s) (5).
  15. Remove the slack adjuster (4).
  16. Inspect the slack adjuster (4) for damage or excessive wear.
  17. Replace the slack adjuster (4) if damage or excessive wear is present.

Installation Procedure


    Object Number: 261832  Size: MH
  1. Lubricate the camshaft splines with anti-seize lubricant.
  2. Install the slack adjuster (4) to the camshaft.
  3. Install the camshaft washer(s) (5).

  4. Object Number: 201813  Size: SH
  5. Install the camshaft snap ring.

  6. Object Number: 201833  Size: SH
  7. Install the slack adjuster control arm washer.
  8. Loosely install the slack adjuster control arm nut.

  9. Object Number: 201826  Size: SH
  10. Rotate the slack adjuster adjusting hex clockwise until the slack adjuster arm hole aligns with the air brake chamber clevis hole.

  11. Object Number: 201820  Size: SH
  12. Install the air brake chamber clevis pin.
  13. Do not install the retainer at this time.
  14. It may be necessary to remove the air brake chamber clevis pin later in order to check installation.


    Object Number: 201829  Size: SH

    Notice: Excessive positioning force may damage the air brake automatic slack adjuster control arm. Most adjusters will be equipped with an installation indicator. The indicator must fall within the slot for proper installation. Incorrect air brake automatic slack adjuster control arm position can cause tight or dragging brakes.

  15. Adjust the slack adjuster control arm. Rotate the control arm counterclockwise away from the slack adjuster adjusting hex. Continue the rotation towards the air brake chamber until the slack adjuster control arm comes to a definite internal stop.
  16. Use a plastic mallet in order to tap the slack adjuster control arm into position if necessary.


    Object Number: 201833  Size: SH

    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.

    Important: Ensure that the slack adjuster control arm does not move from the correct position while tightening the slack adjuster control arm nut.

  17. Install the slack adjuster control nut.
  18. Tighten
    Tighten the slack adjuster control arm nut to 17 N·m (13 lb ft).

  19. Adjust the brakes. Refer to Air Drum Brake Adjustment .
  20. Start the engine.
  21. Charge the system to the air compressor governor valve cut-out point.
  22. Stop the engine.
  23. Inspect the air brake automatic slack adjuster for proper installation.
  24. Verify that the installation indicator is within the slot.

  25. Object Number: 201820  Size: SH
  26. Remove the air brake chamber clevis pin.
  27. Align the air brake chamber clevis hole and the slack adjuster arm hole.
  28. Repeat steps 7-15 if the air brake chamber clevis retracts towards the air brake chamber when you remove the air brake chamber clevis pin.
  29. Install the air brake chamber clevis pin.
  30. Install the air brake chamber clevis pin cotter pin.

  31. Object Number: 201843  Size: SH
  32. Check the slack adjuster adjusting hex torque.
  33. Use a pound inch torque wrench in order to rotate the slack adjuster adjusting hex counterclockwise.
  34. The slack adjuster clutch should not slip at a torque less than 18 N·m (13 lb ft).
  35. A racheting sound occurs when the clutch slips. Replace the slack adjuster if the clutch slips at a lesser torque.

  36. Start the engine.
  37. Charge the system to the air compressor governor valve cut-out point.
  38. Stop the engine.
  39. Uncage the air brake chambers. Refer to Caging the Rear Air Brake Chamber .
  40. Check for proper brake operation.
  41. Set the parking brake.
  42. Remove the wheel blocks.