Complete removal and replacement of the power steering gear box (recirculating ball type) on a 1966 Corvette with 327ci V8, including pitman arm separation and fluid system refill.

Warnings

Tools required

Parts

• Power steering gear box (recirculating ball type) × 1 — Use OEM specification or Saginaw 605 replacement
• Pitman arm nut × 1 — Use OEM specification
• Steering gear mounting bolt kit × 1 — Use OEM specification
• Power steering pressure line sealing washer set × 1 — Use OEM specification
• Power steering return line O-ring × 1 — Use OEM specification

Fluids

• GM Power Steering Fluid — 1 qt

Preparation

1. Park vehicle on level surface and apply parking brake firmly.
2. Place wheel chocks behind rear wheels.
3. Disconnect negative battery cable to prevent accidental starter engagement while working near steering components.
4. Allow engine to cool completely if recently operated - power steering fluid retains heat.
5. Clean the steering gear box area with degreaser to improve visibility and prevent contamination during line disconnection.
6. Turn steering wheel to center position and lock steering column if possible.
7. Place drain pan under steering gear box area to catch fluid spillage.

Procedure

1. 1

   Raise and support vehicle
   Raise the front of the vehicle using a floor jack at the front crossmember. Support securely on jack stands positioned under the frame rails behind the front wheels. Ensure vehicle is stable before working underneath. The vehicle should be high enough to provide comfortable access to the steering gear box area from below.
2. 2

   Mark pitman arm alignment
   Locate the pitman arm where it connects to the steering gear sector shaft on the driver's side of the frame. Using a scribe, punch, or paint marker, make alignment marks across both the pitman arm and the sector shaft splines. These marks must align during reassembly to maintain proper steering wheel centering. Take a reference photo if possible.
3. 3

   Remove pitman arm retaining nut
   Using a 1-1/16" socket or wrench, remove the castellated nut securing the pitman arm to the sector shaft. There should be a cotter pin through the castellated nut - remove this first by straightening the legs and pulling it out. Keep the nut for reference but plan to replace with new hardware.
4. 4

   Separate pitman arm from sector shaft
   Install a pitman arm puller onto the pitman arm according to the tool manufacturer's instructions. The puller should press against the end of the sector shaft while pulling the pitman arm body. Tighten the puller gradually and evenly. The taper joint will separate with a loud pop - maintain control of the arm. Do not strike the arm or use heat, as this can damage the taper or sector shaft splines.
5. 5

   Disconnect center link from pitman arm
   With the pitman arm separated from the sector shaft, disconnect the center link ball joint from the pitman arm if necessary for clearance. This typically requires removing the cotter pin and castle nut, then using a pickle fork or ball joint separator. Support the center link with wire to prevent strain on other steering components.
6. 6

   Disconnect power steering pressure line
   Using a flare nut wrench (typically 5/8" or 3/4"), carefully loosen the pressure line fitting at the steering gear box inlet port. The fitting is located on the driver's side of the gear box. Expect power steering fluid to drain from this connection - position drain pan accordingly. Once loose, unthread the fitting by hand and remove the pressure line. Immediately plug or cap the line and gear box port to prevent contamination and further fluid loss.
7. 7

   Disconnect power steering return line
   The return line typically connects to the steering gear box via a lower port using either a threaded fitting or a clamp-style connection. If threaded, use a flare nut wrench to disconnect. If clamped, use pliers to release the spring clamp and slide it back on the hose, then twist and pull the hose from the fitting. Allow fluid to drain into the pan. Cap or plug the port to prevent debris entry.
8. 8

   Remove steering gear mounting bolts
   Locate the three mounting bolts securing the steering gear box to the driver's side frame rail. These are typically 9/16" or 5/8" head bolts arranged in a triangular pattern. Support the weight of the gear box with one hand or have an assistant hold it. Remove all three mounting bolts, keeping track of any washers or spacers. Note the position of any mounting brackets that may be attached.
9. 9

   Remove steering gear box from vehicle
   With all mounting bolts removed, carefully maneuver the steering gear box away from the frame rail. The sector shaft will need to clear the frame opening. Rotate and angle the gear box as needed - it may be necessary to turn the stub shaft to change the sector shaft angle for clearance. Lower the gear box down and out from under the vehicle. Be mindful of the weight (approximately 15-18 pounds) and awkward shape.
10. 10

    Inspect mounting location and prepare new gear box
    Clean the frame rail mounting surface with a wire brush and brake cleaner. Inspect the mounting bolt holes for damage or stripped threads. Check the condition of the frame rail for cracks or excessive rust. Remove all caps and plugs from the new steering gear box ports. Apply a thin film of thread sealant to the pressure and return port threads if required by the replacement gear box manufacturer's instructions.
11. 11

    Install new steering gear box to frame
    Maneuver the new steering gear box into position, routing the sector shaft through the frame opening. Align the three mounting holes with the frame rail. Thread in all three mounting bolts by hand first to ensure proper alignment. Once all bolts are started, tighten them in a star pattern (alternating positions) to the proper torque specification. Verify the gear box sits flush against the frame rail with no gaps.
12. 12

    Connect power steering return line
    Install a new O-ring onto the return line fitting if applicable (lubricate lightly with power steering fluid). Connect the return line to the steering gear box port, either threading the fitting by hand until snug then tightening with a flare nut wrench, or pushing the hose onto the barbed fitting and securing with a new clamp positioned 1/4" from the hose end.
13. 13

    Connect power steering pressure line
    Install new sealing washers onto the pressure line banjo fitting or flare fitting as applicable. Thread the pressure line fitting into the steering gear box inlet port by hand, ensuring it threads smoothly without cross-threading. Once hand-tight, use a flare nut wrench to tighten to the proper torque specification. Do not overtighten, as this can damage the aluminum gear box housing.
14. 14

    Install pitman arm to sector shaft
    Clean the sector shaft splines and pitman arm splines with brake cleaner. Ensure both are completely dry. Align the marks made during disassembly and slide the pitman arm onto the sector shaft, ensuring the splines engage in the correct position. The arm should slide on relatively easily until it reaches the taper. Install the new castellated nut and tighten to the proper torque specification. The cotter pin holes should align - if not, tighten slightly more (never back off to align). Install a new cotter pin and bend the legs to secure.
15. 15

    Reconnect center link to pitman arm
    If the center link was disconnected, reattach it to the pitman arm ball stud. Install the castle nut and tighten to specification, then install a new cotter pin. Ensure the ball joint moves freely without binding.
16. 16

    Fill and bleed power steering system
    Lower the vehicle to the ground. Locate the power steering reservoir (mounted on the driver's side of the engine). Fill the reservoir to the COLD mark with GM Power Steering Fluid. Start the engine and immediately turn the steering wheel slowly from lock to lock 5-6 times without holding it at either extreme. Check fluid level and add as necessary - expect the level to drop as the system fills. Repeat the lock-to-lock procedure until no more air bubbles appear in the reservoir and the fluid level stabilizes. Check all connections for leaks while the system is pressurized.

Reassembly

1. Ensure all hydraulic fittings are tightened to specification and show no signs of leakage during initial system pressurization.
2. Verify the pitman arm alignment marks are properly aligned - incorrect alignment will result in off-center steering wheel position.
3. Double-check that all mounting bolts are torqued to specification and that the steering gear box is seated flush against the frame.
4. Reconnect the negative battery cable.

Verification

• With engine running, turn steering wheel slowly from lock to lock and verify smooth operation with no binding, unusual noises, or fluid leaks.
• Check power steering fluid level with engine at operating temperature and add if necessary to bring to HOT mark on reservoir.
• Perform a test drive in a safe area, verifying steering responds correctly with proper assist in both directions and returns to center normally.
• Verify steering wheel is centered when driving straight - if not, the pitman arm may be installed one spline off and must be corrected.
• Recheck all hydraulic connections for leaks after test drive and during the first 100 miles of operation.
• Inspect power steering fluid level after 50 miles and 100 miles of operation, topping off as necessary.

More procedures for this vehicle