This procedure covers the removal and replacement of the upper ball joint on the front suspension of a 2015-2020 Ford F-150 with 3.5L EcoBoost engine.

Warnings

Tools required

Parts

• Upper ball joint assembly × 1 — Motorcraft or equivalent for F-150 4WD/RWD
• Ball joint cotter pin × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Loosen wheel lug nuts while vehicle is on ground
3. Raise front of vehicle and support with jack stands under frame rails
4. Remove wheel and tire assembly completely
5. Spray ball joint nut, taper, and any corroded fasteners with penetrating oil and allow to soak

Procedure

1. 1

   Access upper ball joint
   Locate the upper ball joint at the top of the steering knuckle where it connects to the upper control arm. Inspect the area for any additional components that may interfere with access. On some configurations, the brake line bracket may need to be temporarily repositioned.
2. 2

   Remove ball joint cotter pin
   Straighten the cotter pin legs using pliers or a punch. Pull the cotter pin out through the castle nut slot. If the pin is corroded and breaks, use a small punch to drive out the remaining pieces. Discard the old cotter pin.
3. 3

   Remove ball joint castle nut
   Using the appropriate socket, remove the castle nut from the upper ball joint stud. Do not remove completely if using a ball joint separator that requires load on the taper. Keep the nut backed off but threaded on a few turns to prevent the knuckle from dropping suddenly when the taper breaks free.
4. 4

   Separate ball joint from knuckle
   Position the ball joint separator between the upper control arm and the steering knuckle. Apply pressure to the separator tool while striking the knuckle boss area with a hammer to shock the taper loose. Alternatively, use a pickle fork driven between the joints. Once the taper breaks free, remove the castle nut completely and lower the knuckle away from the upper control arm.
   ⚠The steering knuckle will drop when the ball joint separates. Support it with a jack or wire to prevent damage to brake lines and ABS wiring.
5. 5

   Support steering knuckle assembly
   Use a floor jack under the lower control arm or wire/bungee cord from the frame to support the steering knuckle and prevent strain on the brake hose and ABS sensor wiring. Ensure the assembly is stable before proceeding.
6. 6

   Remove ball joint from control arm
   If the ball joint is riveted to the upper control arm (original equipment), drill out the rivets using progressively larger drill bits, then chisel off the rivet heads. If the ball joint is bolted (previous replacement), remove the retaining bolts. Remove the old ball joint from the control arm. Clean the mounting surface thoroughly with a wire brush.
7. 7

   Install new ball joint to control arm
   Position the new ball joint in the upper control arm mounting location. Install the supplied bolts and nuts (replacement ball joints come with bolt-in hardware). Hand-tighten all fasteners first to ensure proper alignment, then torque to the ball joint manufacturer's specification (typically included with the part). Ensure the ball joint boot is not twisted or damaged during installation.
8. 8

   Connect ball joint to knuckle
   Raise the steering knuckle assembly to align the upper ball joint stud with the hole in the top of the knuckle. Insert the stud through the knuckle. Clean the threads of the ball joint stud with a wire brush before installing the nut.
9. 9

   Torque ball joint nut and install cotter pin
   Thread the new castle nut onto the ball joint stud. Torque the nut to 117 Nm (86 lb-ft). The castle nut slots must align with the cotter pin hole in the stud. If slots do not align, tighten the nut further (never loosen) until the next slot aligns with the hole. Insert a new cotter pin through the castle nut and stud hole, then bend the legs to secure.
   ⚠Never back off the castle nut to align the cotter pin hole. Only tighten to the next alignment position.
   Torque spec

   Ball Joint Nut101 Nm (75 lb-ft)
10. 10

    Remove knuckle support and verify installation
    Remove the jack or support wire from the steering knuckle assembly. Verify the ball joint stud moves freely in its socket with normal suspension articulation. Check that all fasteners are tight and the cotter pin is properly installed and bent.
11. 11

    Reinstall wheel and lower vehicle
    Reinstall the wheel and tire assembly. Thread lug nuts by hand to prevent cross-threading. Torque lug nuts in a star pattern to 156 Nm (115 lb-ft). Lower the vehicle to the ground. With the vehicle weight on the wheels, recheck lug nut torque.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)

Reassembly

1. Ensure all suspension components are properly seated before lowering vehicle completely
2. Test drive the vehicle at low speed in a safe area to verify proper suspension operation
3. Listen for any unusual noises from the front suspension during turns and over bumps

Verification

• Verify the steering knuckle moves smoothly through its full range of motion without binding
• Check that there is no excessive play in the upper ball joint by attempting to move the wheel top-to-bottom with the wheel off the ground
• Confirm the cotter pin is properly installed and secured
• Perform a visual inspection of the ball joint boot for tears or improper seating
• Test drive and verify normal steering feel and no clunking noises from the front suspension
• Schedule a professional alignment within 50 miles of completing this repair

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