Power Steering Gear Box

This procedure covers the removal and replacement of the power steering gear box on a 2007 Ram 3500 with the 5.9L Cummins diesel engine and 4WD.

Warnings

Tools required

Parts

• Power steering gear box × 1 — Use OEM specification
• Pitman arm nut × 1 — Use OEM specification
• Power steering pressure line O-ring × 1 — Use OEM specification
• Power steering return line O-ring × 1 — Use OEM specification
• Gear box mounting bolts × 3 — Use OEM specification (optional, inspect condition)

Fluids

• ATF+4 power steering fluid — 2.5 qt

Preparation

1. Park vehicle on level surface and set parking brake firmly
2. Place wheel chocks behind rear wheels
3. Center the steering wheel and lock in place with steering wheel holder if available, or mark position
4. Raise front of vehicle with floor jack and support securely on jack stands under frame rails
5. Remove both front wheels to improve access
6. Place drain pan under power steering gear box area
7. Use turkey baster or fluid pump to remove as much power steering fluid as possible from reservoir

Procedure

1. 1

   Disconnect intermediate steering shaft
   Locate the intermediate steering shaft coupler at the gear box input shaft. Mark the orientation of the shaft to the gear box with paint or a scribe for proper reassembly alignment. Remove the pinch bolt securing the intermediate shaft to the gear box input shaft. Slide the intermediate shaft coupler off the input shaft splines, working it free of the master spline; you may need to reposition the shaft to clear it. You may need to turn the steering wheel slightly to access the pinch bolt.
2. 2

   Remove Pitman arm nut
   Locate the Pitman arm where it connects to the gear box sector shaft on the driver's side. Mark the relationship between the Pitman arm and sector shaft with paint or a scribe. Note that the sector shaft has a master (wide) spline that indexes the Pitman arm to the correct orientation, but marking aids reassembly. Remove the castle nut or lock nut securing the Pitman arm to the sector shaft. If equipped with a cotter pin, remove it first.
3. 3

   Separate Pitman arm from gear box
   Install the Pitman arm puller onto the Pitman arm. Ensure the puller is properly seated and centered. Tighten the puller forcing screw to apply pressure to the sector shaft while supporting the Pitman arm. The arm should release with a loud pop. Do not strike the Pitman arm with a hammer as this can damage the gear box. Once separated, remove the Pitman arm completely and set aside.
   ⚠The Pitman arm will release suddenly under tension. Keep hands clear of the puller and ensure proper tool engagement before applying force.
4. 4

   Disconnect hydraulic lines
   Position drain pan directly under the gear box hydraulic connections. Using line wrenches to prevent rounding, disconnect the power steering pressure line from the gear box input fitting. Immediately cap or plug the line to minimize fluid loss. Disconnect the power steering return line from the gear box. Allow all fluid to drain from the gear box and lines into the drain pan. Cap or plug all open fittings to prevent contamination.
   ⚠Power steering fluid will spill when lines are disconnected. Wear eye protection and have rags ready to contain spillage.
5. 5

   Remove gear box mounting bolts
   Locate the three gear box mounting bolts that secure the gear box to the driver-side frame rail. These are accessed from the frame rail area and may require removal from both the inboard and outboard sides. Support the gear box with one hand or have an assistant hold it. Remove all three mounting bolts while supporting the gear box weight. The gear box is heavy (approximately 20-30 lbs) and awkward to handle.
6. 6

   Remove gear box from vehicle
   Carefully maneuver the gear box down and out of the frame mounting area. You may need to rotate it to clear the frame rail and other components. The input shaft will need to clear the steering shaft opening in the frame. Remove the gear box from under the vehicle. Inspect the frame mounting area for damage or excessive wear.
7. 7

   Prepare new gear box for installation
   Unbox the new or remanufactured gear box and verify it matches the original unit. Install new O-rings on the pressure and return line fittings, lightly lubricating them with clean ATF+4. Check that the input shaft is centered and can rotate freely. Compare the mounting bolt pattern and shaft lengths to the original unit. If the new gear box is not pre-filled with fluid, add ATF+4 per manufacturer instructions.
8. 8

   Install gear box into frame
   Maneuver the new gear box up into position from under the vehicle. Align the mounting holes with the frame rail mounting points. The input shaft should extend through the frame opening toward the steering column. Support the gear box and start all three mounting bolts by hand to ensure proper thread engagement before tightening any of them.
9. 9

   Tighten gear box mounting bolts
   Tighten the three gear box mounting bolts in a progressive pattern, alternating between bolts to pull the gear box evenly against the frame. These fasteners are critical to steering safety. Torque the gear box mounting bolts to the Mopar FSM specification for this vehicle (verify in service manual; approximately 150 ft-lbs) using a torque wrench. Verify the gear box is seated flush against the frame with no gaps.
10. 10

    Connect hydraulic lines
    Remove the protective caps from the gear box fittings and hydraulic lines. Inspect the line fittings for damage or debris and clean if necessary. Connect the power steering pressure line to the gear box pressure fitting and tighten with a line wrench. Connect the return line to the return fitting and tighten. Ensure both connections are snug but do not overtighten as this can damage the fittings or O-rings.
11. 11

    Install Pitman arm to sector shaft
    Clean the sector shaft splines and Pitman arm taper thoroughly with brake cleaner. Align the marks made during disassembly to ensure the Pitman arm is installed in the exact same orientation. Slide the Pitman arm onto the sector shaft, aligning the splines and index marks. Install the Pitman arm nut and torque to the Mopar FSM specification for this vehicle (verify in service manual; approximately 185 ft-lbs) using a torque wrench. Install new cotter pin if equipped. Install new cotter pin if equipped.
12. 12

    Connect intermediate steering shaft
    Align the intermediate steering shaft with the gear box input shaft, matching the marks made during disassembly. Ensure the shaft coupling engages fully onto the input shaft splines. The flat on the shaft should align with the flat in the coupling. Install the pinch bolt and tighten securely. Verify the connection is solid with no play.
13. 13

    Fill and bleed power steering system
    Fill the power steering reservoir with fresh ATF+4 to the cold fill line. Start the engine and turn the steering wheel slowly from lock to lock several times while keeping the engine at idle. Check the reservoir level frequently and add fluid as needed. Continue this process until no air bubbles appear in the reservoir and the fluid level stabilizes. Check all connections for leaks while the system is running.

Reassembly

1. Reinstall front wheels and tighten lug nuts in star pattern
2. Lower vehicle to ground and torque lug nuts to specification
3. Remove steering wheel lock or holder
4. Top off power steering reservoir to proper cold level
5. Clean any spilled power steering fluid from components and frame

Verification

• Start engine and verify no leaks from gear box or hydraulic line connections
• With engine running, turn steering wheel fully left and right to verify smooth operation with no binding or unusual noises
• Check power steering fluid level and top off if necessary
• Test drive vehicle at low speed to verify proper steering function and no wandering or pulling
• Verify steering wheel is still centered when driving straight
• Recheck all mounting bolts and hydraulic connections for tightness after test drive
• Inspect underneath vehicle for any power steering fluid leaks after test drive
• Schedule front end alignment if steering wheel is not centered or vehicle pulls to one side

Related trouble codes on this vehicle

Codes that commonly send this job to the bay — tap one for symptoms, causes, and diagnostic steps.

Chasing one of these codes and not sure which part is guilty? Ask a master mechanic about YOUR car →

More procedures for this vehicle