Knuckle/Spindle - Front

This procedure covers removal and replacement of the front spindle (steering knuckle) on a 1972 Ford F-100 with twin I-beam front suspension, including removal of hub, bearings, brake components, and ball joint separation.

Warnings

Tools required

Parts

• Front spindle/steering knuckle × 1 — Use OEM specification
• Inner wheel bearing cone and cup set × 1 — Timken SET2 or equivalent
• Outer wheel bearing cone and cup set × 1 — Timken SET1 or equivalent
• Grease seal (inner) × 1 — National 472271 or equivalent
• Cotter pin (spindle nut) × 1 — 1/8" x 1.5"
• Cotter pin (upper ball joint) × 1 — Use OEM specification
• Cotter pin (lower ball joint) × 1 — Use OEM specification
• Cotter pin (tie rod end) × 1 — Use OEM specification
• High-temperature wheel bearing grease × 1 — NLGI Grade 2
• Brake cleaner × 1 — Aerosol can

Fluids

• DOT 3 brake fluid — 0.25 qt

Preparation

1. Park vehicle on level surface and apply parking brake firmly.
2. Place wheel chocks behind rear wheels.
3. Loosen front wheel lug nuts 1/2 turn while vehicle is still on the ground.
4. Raise front of vehicle with floor jack at frame rail or designated lift point.
5. Support vehicle with jack stands under the frame rails behind the front suspension.
6. Remove wheel and tire assembly completely.
7. Inspect spindle and surrounding components for visible damage or cause of failure.

Procedure

1. 1

   Remove brake caliper
   Use a C-clamp or brake caliper compression tool to push the caliper piston back into the bore slightly to relieve pressure. Remove the 2 caliper mounting bolts from the rear of the caliper anchor plate. Lift the caliper off the rotor and support it with wire or a bungee cord from the frame or I-beam. Do not let the caliper hang by the brake hose.
2. 2

   Remove brake rotor and dust cap
   Remove the dust cap from the center of the hub using pliers or by tapping around the edge with a screwdriver and hammer. Remove the cotter pin from the spindle nut and discard. Remove the spindle nut and washer. Pull the rotor/hub assembly straight off the spindle, being careful to catch the outer wheel bearing as it comes free. Set the rotor aside on a clean surface.
3. 3

   Remove grease seal and inner bearing
   With the rotor removed, use a seal puller or large screwdriver to pry out the inner grease seal from the back of the hub. This will expose the inner wheel bearing cone. Remove the inner bearing cone and set aside. If bearings are being reused, keep them with their respective races and mark them as left or right side.
4. 4

   Disconnect tie rod end
   Locate the tie rod end attached to the spindle steering arm. Remove the cotter pin and discard. Loosen the castle nut but do not remove it completely (leave it flush with the end of the stud). Use a ball joint separator or pickle fork to break the taper loose from the spindle. Once free, remove the castle nut and separate the tie rod end from the spindle arm.
5. 5

   Disconnect upper ball joint
   Locate the upper ball joint stud where it passes through the top of the spindle. Remove the cotter pin and discard. Loosen the castle nut approximately 2-3 turns but leave it threaded on the stud to prevent sudden separation. Strike the side of the spindle boss near the upper ball joint stud sharply with a hammer to shock the taper loose. Alternatively, use a ball joint separator tool. Once the taper breaks free, remove the castle nut completely.
   ⚠The spindle may drop suddenly when the upper ball joint releases. Support the spindle with one hand or position a floor jack under it.
6. 6

   Disconnect lower ball joint and remove spindle
   Locate the lower ball joint stud where it passes through the bottom of the spindle. Remove the cotter pin and discard. Loosen the castle nut approximately 2-3 turns but leave it threaded on. Use a ball joint separator to break the taper free, then remove the castle nut completely. Carefully lower and remove the spindle from the I-beam assembly. Note the orientation of the spindle for reassembly.
   ℹ️The spindle is heavy and awkward. Be prepared to support its weight as the lower ball joint releases.
7. 7

   Inspect and clean mating surfaces
   Inspect both ball joint tapers on the I-beam for damage, wear, or debris. Clean the tapers thoroughly with a wire brush and brake cleaner. Inspect the ball joint boots for tears or damage. If ball joints show excessive play or damage, they should be replaced before installing the new spindle. Clean the tie rod end taper as well.
8. 8

   Install new spindle onto ball joints
   Position the new spindle onto the lower ball joint stud first, ensuring the spindle is oriented correctly (brake caliper mounting surface facing forward). Thread the lower castle nut onto the stud but do not tighten fully yet. Lift the spindle and align the upper ball joint stud through the upper spindle bore. Thread the upper castle nut onto the stud. Tighten the upper ball joint castle nut to specification first, then tighten the lower ball joint castle nut to specification. Install new cotter pins through both castle nuts and bend the ends to secure.
9. 9

   Connect tie rod end
   Insert the tie rod end stud through the hole in the spindle steering arm. Thread the castle nut onto the stud and tighten to specification. Align the castle nut slots with the cotter pin hole in the stud (tighten further if necessary to align, never back off). Install a new cotter pin and bend the ends to secure.
10. 10

    Install bearing races in hub
    If new bearings are being installed, drive the old bearing races out of the hub using a brass drift and hammer, working around the circumference evenly. Clean the bearing bores thoroughly with brake cleaner. Install the new inner bearing race first, then the outer bearing race, using a bearing race driver or large socket that contacts only the outer edge of the race. Drive each race in squarely until it seats fully against the shoulder in the hub bore.
11. 11

    Pack and install wheel bearings
    Pack the inner and outer bearing cones thoroughly with high-temperature wheel bearing grease. Work grease into the bearing from the large end, forcing grease through the rollers until it appears on the small end. Apply a thin coating of grease to the bearing races in the hub. Place the inner bearing cone into the inner race. Install a new grease seal by tapping it squarely into the hub bore until flush, using a seal driver or large socket that contacts the outer edge only. Apply a thin coat of grease to the seal lip.
12. 12

    Install hub and rotor assembly
    Carefully slide the hub and rotor assembly onto the spindle, being careful not to damage the grease seal. Insert the outer bearing cone into the outer race. Install the washer and spindle nut. While rotating the rotor forward, tighten the spindle nut to 17-25 ft-lb to seat the bearings. Then back the nut off 1/4 turn. Retighten finger-tight only (or until slight drag is felt when spinning the rotor). The rotor should spin freely with only slight drag, with no perceptible play when pushing/pulling on it. Install a new cotter pin through the spindle nut and bend ends. Install the dust cap by tapping it into place evenly.
13. 13

    Reinstall brake caliper
    Remove the wire or support holding the brake caliper. Position the caliper over the rotor and align the mounting bolt holes. Install the 2 caliper mounting bolts and tighten to specification. Pump the brake pedal several times until firm to reseat the caliper piston against the rotor.
14. 14

    Install wheel and lower vehicle
    Install the wheel and tire assembly onto the hub. Thread all lug nuts on by hand. Lower the vehicle until the tire just contacts the ground but the suspension is not fully loaded. Tighten the lug nuts in a star pattern to 103.0 lb-ft (140.0 Nm). Lower the vehicle completely and remove jack stands. Torque lug nuts again to final 103.0 lb-ft (140.0 Nm) in a star pattern.

Reassembly

1. After installation, check brake fluid level in the master cylinder reservoir and top off with DOT 3 brake fluid if necessary.
2. Test brake pedal feel before moving the vehicle. Pedal should be firm after pumping 2-3 times.
3. After the first 50-100 miles, recheck wheel bearing adjustment by jacking up the front wheel and checking for play. Slight drag with no play is correct.

Verification

• Start the engine and verify power steering operation by turning the wheel lock to lock.
• Perform a low-speed test drive (under 15 mph in a safe area) to verify steering response and brake function.
• Listen for any unusual noises from the wheel bearing area during turning and braking.
• After the test drive, recheck for any looseness at the wheel by grasping the tire at 12 and 6 o'clock and attempting to rock it. No perceptible movement should be felt.
• Inspect for any brake fluid leaks at the caliper and brake line connections.
• Schedule a professional alignment check, as replacing the spindle may have affected toe and camber settings.

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