Power Steering Hose - High Pressure

This procedure covers the replacement of the high-pressure power steering hose on a 2007 Ram 3500 with the 5.9L Cummins diesel engine and 4WD.

Warnings

Tools required

Parts

• Power steering high-pressure hose × 1 — Use OEM specification
• High-pressure line O-rings (if not included with hose) × 2 — Use OEM specification

Fluids

• ATF+4 — 2.5 qt

Preparation

1. Park vehicle on level ground and engage parking brake
2. Place wheel chocks behind rear wheels
3. Allow engine to cool completely if recently operated
4. Remove power steering fluid reservoir cap to relieve any residual pressure
5. Use fluid pump or turkey baster to remove as much fluid as possible from the power steering reservoir
6. Raise front of vehicle with floor jack and support securely on jack stands under the frame rails
7. Remove driver side front wheel for improved access (optional but recommended)

Procedure

1. 1

   Locate and inspect high-pressure hose routing
   The high-pressure hose runs from the power steering pump (mounted on the driver side of the engine) to the steering gear (mounted on the frame rail). Trace the entire hose path to identify the routing and any potential obstacles. Note the position of any clips or brackets securing the hose.
2. 2

   Position drain pan
   Place a large drain pan beneath the power steering pump and steering gear connections. Power steering fluid will drain from both the hose and the pump/gear when disconnected. Have shop rags ready to catch initial spray.
3. 3

   Apply penetrating oil to fittings
   Spray penetrating oil on both the pump-end fitting and the steering gear-end fitting. Allow 5-10 minutes for penetration. These fittings can corrode and seize, especially the steering gear connection which is exposed to road spray.
4. 4

   Disconnect hose at power steering pump
   Using a line wrench to prevent rounding, loosen the high-pressure hose fitting at the power steering pump. Confirm the correct fitting size on the vehicle before applying a wrench. Once loose, unthread by hand and allow fluid to drain into the pan. Immediately cap or plug the pump port with a clean rag to prevent contamination.
5. 5

   Remove hose mounting clips
   Locate and remove any clips or brackets securing the hose to the frame, engine, or body. There is typically at least one clip along the frame rail. These may be push-pin style or bolt-on brackets. Keep track of all hardware for reinstallation.
6. 6

   Disconnect hose at steering gear
   Using a line wrench, loosen the high-pressure hose fitting at the steering gear input port. This connection is usually tighter due to heat cycling and exposure. Once loose, unthread by hand and allow remaining fluid to drain. The fitting may spray initially, so position rags to catch fluid. Cap or plug the steering gear port.
7. 7

   Remove old hose from vehicle
   Carefully maneuver the old hose out of the engine bay, noting the exact routing path. Take photos if necessary to reference during installation. Inspect the hose for signs of failure such as cracks, abrasion, or bulging to confirm replacement was necessary.
8. 8

   Clean connection points
   Remove rags from the pump and steering gear ports. Use a wire brush to clean the threaded fittings on both the pump and steering gear. Inspect for damage or excessive wear. Clean any spilled fluid from surrounding components to prevent contamination of the new hose.
9. 9

   Prepare new hose for installation
   Unpack the new high-pressure hose and verify it matches the old hose configuration. Inspect new O-rings at each fitting and replace if damaged or if new O-rings were supplied separately. Lightly lubricate O-rings with clean ATF+4 to ease installation and prevent tearing.
10. 10

    Route new hose into position
    Following the exact path of the old hose, route the new high-pressure hose from the steering gear area to the power steering pump. Ensure the hose does not contact hot exhaust components, sharp edges, or moving parts. The hose should have a gentle curve without kinks or excessive bending.
11. 11

    Connect hose to steering gear
    Thread the fitting onto the steering gear port by hand to ensure proper alignment and prevent cross-threading. Once hand-tight, use a line wrench to snug the fitting. Do not over-tighten as this can damage the O-ring seal. The fitting should be firmly seated with moderate resistance.
12. 12

    Connect hose to power steering pump
    Thread the fitting onto the power steering pump port by hand to ensure proper alignment. Once hand-tight, use a line wrench to snug the fitting. Apply the same moderate tightening force used at the steering gear connection.
13. 13

    Reinstall mounting clips and brackets
    Secure the hose using all original clips and brackets. Ensure the hose is properly positioned in each clip to prevent vibration and maintain clearance from other components. The hose should be supported but not over-constrained.
14. 14

    Fill power steering system
    Fill the power steering reservoir with fresh ATF+4 to the cold fill mark. Do not overfill. The system capacity is modest, and much of the fluid remains in the pump, lines, and steering gear during hose replacement; verify total capacity against factory specifications.
15. 15

    Bleed air from system
    With the engine off, turn the steering wheel fully left and right several times to work fluid through the system and displace air. Check reservoir level frequently and add fluid as needed. Continue until fluid level stabilizes and no air bubbles are visible in the reservoir. Start the engine and repeat the lock-to-lock steering procedure at idle. Check for leaks at both hose connections while turning the wheel.

Reassembly

1. Reinstall driver side front wheel if removed and torque lug nuts to specification
2. Lower vehicle from jack stands
3. Install power steering reservoir cap securely
4. Check fluid level after vehicle has been driven and add if necessary to bring to hot full mark

Verification

• With engine running, check both hose connections for leaks while turning steering wheel lock-to-lock
• Verify no drips or seepage at fittings after 5 minutes of operation
• Check power steering fluid level and confirm it is at the appropriate mark (hot or cold)
• Test drive vehicle and verify normal power steering operation with no unusual noises
• Re-check connections and fluid level after test drive
• Inspect ground beneath vehicle after overnight parking to confirm no leaks

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