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Steering Gear Pitman Shaft Over-Center Preload Adjustment - Off Vehicle 708 Model

  1. Turn the pitman shaft adjuster screw counterclockwise until the pitman shaft adjuster screw extends fully. Then turn the pitman shaft adjuster screw back 1/2 turn clockwise.
  2. Rotate the stub shaft from stop to stop. Count the number of turns.
  3. Starting at either stop, turn the stub shaft back 1/2 the total number of turns. This is the center of the gear.
  4. The flat on the stub shaft should face upward when the gear is in the center. The flat on the stub shaft should be parallel with the side cover.


    Object Number: 314006  Size: SH
  5. Align the master spine on the pitman shaft (2) with the adjuster screw (1).

  6. Object Number: 666  Size: SH
  7. Place the torque wrench, with the handle in the vertical position, on the stub shaft. Rotate the torque wrench 45 degrees to each side of the center. Record the highest drag torque measure on or near the center.
  8. 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.

  9. Use the following procedure in order to adjust the over-center drag torque:
  10. 6.1. Loosen the adjuster screw jamb nut.
    6.2. Turn the pitman shaft adjuster screw clockwise until the correct drag torque is obtained.
  11. On new steering gears (under 400 miles), add 0.6-1.2 N·m (6-10 lb in) torque to the worm bearing preload torque. Do not exceed a total steering gear preload of 2 N·m (18 lb in).
  12. On used steering gears (400 miles or more), add 0.5-0.6 N·m (4.5 lb in) torque to the worm bearing preload torque. Do not exceed a total steering gear preload of 1.5 N·m (14 lb in).
  13. Tighten
    Tighten the adjuster screw jamb nut to 47 N·m (35 lb ft).

  14. Install the steering gear. Refer to Steering Gear Replacement
  15. Fill the pump reservoir with the power steering fluid.
  16. Bleed the system. Refer to Power Steering System Bleeding .

Steering Gear Pitman Shaft Over-Center Preload Adjustment - Off Vehicle 710 Model

Tools Required

J 7754-01 Torque Wrench


    Object Number: 218934  Size: SH
  1. Always check the worm shaft bearing preload adjustment. Adjust the worm shaft bearing preload, if needed, before performing the pitman shaft over-center preload adjustment.
  2. Turn the over-center adjusting screw all the way out clockwise. Then turn the over-center adjusting screw in 1/2 turn.
  3. Place the J 7754-01 with a 3/4 inch 12-point socket (3) onto the stub shaft.
  4. Rotate the stub shaft from one stop to the other. Count the turns. Turn the stub shaft back to center.
  5. Check the over-center preload by rotating the torque wrench through a 180 degree arc on each side of the center. Note the highest readings. The readings must be 0.8-1.9 N·m (7-17 lb in).
  6. 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.

  7. Turn the over-center adjusting screw counterclockwise until the torque wrench shows a reading of 0.7-1.1 N·m (6-10 lb in) higher than the previous reading. The total reading must not exceed 3 N·m (27 lb in).
  8. Tighten
    Tighten the adjustment lock nut (1) to 89 N·m (66 lb in).

  9. Check the adjustment. Adjust again if necessary.
  10. Connect the hydraulic hoses following the tag locations.
  11. Tighten
    Tighten the high pressure connections to 38 N·m (28 lb ft).

  12. Connect the cardan clamp.
  13. Install the cardan clamp bolt. Adjust the cardan clamp. Refer to Steering Wheel and Column.
  14. Connect the pitman arm. Refer to Pitman Arm Replacement in Steering Linkage.

Steering Gear Pitman Shaft Over-Center Preload Adjustment - Off Vehicle Saginaw - 708 Model

Steering Gear Adjustments

Important: Any steering gear adjustment is made only as a correction and not as a periodic adjustment.

Remove the gear from the vehicle prior to any adjustments.

  1. Drain the power steering fluid from the gear.
  2. Mount the gear in a vise.
  3. Important: 

       • Adjust the worm thrust bearing preload first, then adjust the pitman shaft over-center preload.
       • The worm thrust bearing preload is controlled by the amount of compression force exerted by the adjuster nut assembly on the flat races.
       • The pitman shaft over-center preload is controlled by the pitman shaft adjuster screw, which determines the clearance between the rack piston and the pitman shaft sector teeth.

  4. Adjust the following:
  5. 3.1. The worm thrust bearing preload
    3.2. The pitman shaft over-center preload adjustment

Worm Thrust Bearing Preload Adjustment

Tools Required

J 42882 Adjuster Nut Socket


    Object Number: 321974  Size: SH
  1. Rotate the stub shaft (3) back and forth in order to drain the power steering fluid.
  2. Remove the coupling shield retainer and the lock nut (2) from the steering gear housing (1) using a drift and a hammer.

  3. Object Number: 321992  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.

  4. Turn the adjuster nut assembly (1) clockwise using J 42882 until the adjuster nut assembly (1) and the thrust support assembly (2) are firmly bottomed in the steering gear housing (3).
  5. Tighten
    Tighten the adjuster nut assembly (1) to 28-31 N·m (20-23 lb ft).


    Object Number: 321996  Size: SH
  6. Place an index mark (1) on the steering gear housing (4) parallel with one of the holes (3) in the adjuster nut assembly (2).

  7. Object Number: 321997  Size: SH
  8. Measure back counterclockwise 13 mm (½ inch).
  9. Place a second mark (2) on the steering gear housing (1).

  10. Object Number: 322000  Size: SH
  11. Using J 42882 and a torque wrench, turn the adjuster nut assembly (1) counterclockwise 15-25 degrees in order to align the hole (2) in the adjuster nut assembly (1) with the second mark (4) on the steering gear housing (3).

  12. Object Number: 321974  Size: SH
  13. Install the coupling shield retainer and the lock nut (2).
  14. Hold the adjuster nut assembly in position in order to maintain alignment of the marks.
  15. Tighten the coupling shield retainer and the lock nut (2) using a drift in a notch.

Pitman Shaft Over-Center Preload Adjustment


    Object Number: 322005  Size: SH
  1. Rotate the stub shaft (3) back and forth in order to drain the power steering fluid.
  2. Loosen the adjuster lock nut (4).
  3. Turn the pitman shaft adjuster screw (1) counterclockwise until the screw is fully extended.
  4. Turn the pitman shaft adjuster screw (1) clockwise 1 full turn.
  5. Rotate the stub shaft (3) from stop to stop, using a 12-point socket while counting the number of turns.
  6. Starting at either stop, turn the stub shaft (3) back half of the total number of turns. This is the center of the gear.

  7. Object Number: 322006  Size: SH
  8. Ensure that the gear is centered by verifying the following items:
  9. • The flat on the stub shaft (3) faces upward.
    • The flat on the stub shaft (3) is parallel with the side cover (2).
  10. Align the master spline (5) on the pitman shaft (4) with the adjuster screw (1).

  11. Object Number: 322007  Size: SH
  12. Place a torque wrench on the stub shaft (2) with the handle in the vertical position.
  13. Rotate the stub shaft (2) 45 degrees from each side of the center of the stub shaft. The stub shaft (2) must rotate smoothly.
  14. Record the worm bearing preload measured on or near the center (1). The recorded bearing preload must be 0.7-1.7 N·m (6-15 lb in) with the worm and the ballnut installed. If the torque is outside of this range, readjust or repair the steering gear assembly as required.
  15. In order to obtain the correct preload torque, adjust the over-center torque by turning the pitman shaft adjuster screw clockwise.
  16. Add 0.7-1.1 N·m (6-10 lb in) torque to the previously measured worm bearing preload torque.
  17. Tighten
    Tighten the adjuster lock nut to 49 N·m (36 lb ft). Prevent the adjuster screw from turning while tightening the adjuster lock nut.