This procedure covers the removal and replacement of the front steering knuckle/spindle assembly on a 2021-2024 Ford F-150 with 3.5L EcoBoost engine, including disconnection of brake components, wheel bearings, and suspension components.

Warnings

Tools required

Parts

• Front steering knuckle assembly × 1 — Use OEM specification
• Ball joint cotter pin × 1 — Use OEM specification
• Brake caliper mounting bolts (if damaged) × 2 — Use OEM specification
• Thread locker (medium strength) × 1 — Loctite 243 or equivalent
• Anti-seize compound × 1 — Use OEM specification

Fluids

• Motorcraft DOT 4 LV Brake Fluid — 0.5 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Loosen front wheel lug nuts while vehicle is on ground
3. Raise front of vehicle and secure with jack stands under frame rails
4. Remove front wheel completely
5. Mark or photograph routing of ABS sensor wire for reassembly reference
6. Spray all fasteners with penetrating oil and allow to soak for 15 minutes

Procedure

1. 1

   Remove brake caliper
   Remove the two brake caliper mounting bolts from the rear of the caliper bracket. Carefully lift the caliper off the rotor without letting it hang by the brake hose. Suspend the caliper from the frame using a wire hanger or bungee cord to prevent stress on the brake line.
   Torque spec

   Mounting Bolts31 Nm (23 lb-ft)
2. 2

   Remove brake rotor and ABS sensor
   Remove the brake rotor by pulling it straight off the hub. If stuck, use penetrating oil and light taps with a dead blow hammer. Disconnect the ABS wheel speed sensor electrical connector. Remove the ABS sensor mounting bolt and carefully extract the sensor from the knuckle. Keep sensor away from magnetic debris.
3. 3

   Disconnect tie rod end
   Remove the cotter pin from the tie rod end castle nut. Loosen but do not fully remove the castle nut. Use a ball joint separator tool to break the taper between the tie rod end and the knuckle. Once separated, remove the nut completely and separate the tie rod end from the knuckle.
4. 4

   Disconnect sway bar link
   Locate the sway bar link connection at the lower control arm or knuckle. Hold the ball stud with an Allen key to prevent rotation. Remove the sway bar link nut and disconnect the link from the knuckle assembly.
   Torque spec

   Sway Bar Link71 Nm (52 lb-ft)
5. 5

   Disconnect lower ball joint
   Remove the cotter pin from the lower ball joint castle nut. Loosen the ball joint nut but leave it threaded on a few turns for safety. Use a ball joint separator to break the taper. Once the joint separates, remove the nut completely and separate the lower control arm from the knuckle.
   ⚠The knuckle assembly will become loose once the ball joint is separated. Support the assembly to prevent it from falling.
   Torque spec

   Ball Joint Nut102 Nm (75 lb-ft)
6. 6

   Remove strut-to-knuckle bolts
   Support the knuckle assembly with one hand or a jack. Locate the two large bolts securing the knuckle to the strut assembly. Remove both strut-to-knuckle bolts completely. The knuckle should now be free from the strut.
   Torque spec

   Strut Bolts133 Nm (98 lb-ft)
7. 7

   Remove knuckle assembly
   Carefully maneuver the knuckle assembly away from the strut and lower control arm. If a hub and bearing assembly is integrated, the entire assembly will come off together. If the CV axle stub shaft is preventing removal, you may need to tap the hub from behind to separate it from the axle splines. Remove the knuckle from the vehicle.
8. 8

   Transfer components to new knuckle
   If replacing only the knuckle, transfer the wheel hub and bearing assembly to the new knuckle if they are separate components. Clean all mating surfaces with a wire brush and brake cleaner. Apply a thin coat of anti-seize to hub mounting surfaces. Install the ABS sensor into the new knuckle and secure with its mounting bolt.
9. 9

   Install knuckle to strut
   Position the new knuckle onto the strut assembly, aligning the bolt holes. Insert both strut-to-knuckle bolts and thread them in by hand first. Torque both bolts to specification using a torque wrench.
   Torque spec

   Strut Bolts133 Nm (98 lb-ft)
10. 10

    Connect lower ball joint
    Align the lower ball joint stud with the hole in the knuckle. Insert the stud through the knuckle and thread on the castle nut. Torque the ball joint nut to specification. Install a new cotter pin through the castle nut and ball joint stud, bending the ends to secure.
    Torque spec

    Ball Joint Nut102 Nm (75 lb-ft)
11. 11

    Reconnect tie rod end
    Insert the tie rod end ball stud into the knuckle. Thread on the castle nut and torque to specification per the service manual (not listed in provided torque specs). Install a new cotter pin and bend to secure. Ensure the tie rod end boot is not damaged.
12. 12

    Reconnect sway bar link
    Connect the sway bar link to the knuckle or lower control arm mounting point. Thread on the nut while holding the ball stud with an Allen key. Torque the nut to specification.
    Torque spec

    Sway Bar Link71 Nm (52 lb-ft)
13. 13

    Reinstall brake components
    Install the brake rotor onto the hub. Position the brake caliper over the rotor and align the mounting bolt holes. Install the caliper mounting bolts and torque to specification. Reconnect the ABS sensor electrical connector. Verify the brake line is not twisted or strained.
    Torque spec

    Mounting Bolts31 Nm (23 lb-ft)
14. 14

    Reinstall wheel and lower vehicle
    Install the wheel onto the hub and thread on all lug nuts by hand. Lower the vehicle until the tire just touches the ground but the suspension is not fully loaded. Torque the lug nuts to specification in a star pattern. Fully lower the vehicle to the ground.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)
15. 15

    Final torque and brake bleeding
    With the vehicle weight on the wheels, verify all fasteners are properly torqued. Pump the brake pedal several times until firm. Check brake fluid level and top off with Motorcraft DOT 4 LV brake fluid if needed. If brake lines were opened, bleed the brake system starting with the wheel furthest from the master cylinder.

Reassembly

1. All torque specifications must be verified with a calibrated torque wrench
2. New cotter pins must be used on all castle nuts - never reuse old cotter pins
3. Ensure ABS sensor wiring is routed away from rotating components and heat sources
4. Verify brake caliper slides freely and brake pads are properly seated

Verification

• Start the engine and verify no ABS warning lights are illuminated on the dashboard
• Test brake pedal feel - it should be firm with no excessive travel
• Perform a steering lock-to-lock test while stationary to check for binding or interference
• Test drive at low speed in a safe area, checking for proper steering response and brake function
• Inspect for any fluid leaks around the brake caliper and ABS sensor area
• Listen for any unusual noises from the suspension during driving and turning
• Have alignment checked and adjusted at a qualified shop - knuckle replacement will affect toe and camber settings

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