This procedure covers the removal and replacement of the rear upper control arm on a 2021-2024 Ford F-150 with 3.5L EcoBoost engine, including ball joint separation and proper torque sequencing.

Warnings

Tools required

Parts

• Rear upper control arm × 1 — Use OEM specification
• Cotter pin for ball joint nut × 1 — Use OEM specification

Preparation

1. Park vehicle on level surface and engage parking brake
2. Place wheel chocks in front of front wheels
3. Loosen rear wheel lug nuts while vehicle is on ground (do not remove)
4. Raise rear of vehicle with floor jack at frame rail
5. Support vehicle with jack stands under frame rails on both sides
6. Remove rear wheel completely

Procedure

1. 1

   Inspect and document suspension position
   Before disassembly, photograph or note the orientation of the upper control arm and suspension geometry for reference during installation. Check for any additional damage to surrounding components.
2. 2

   Remove ball joint cotter pin
   Locate the ball joint nut where the upper control arm connects to the knuckle. Using needle nose pliers, straighten and remove the cotter pin from the ball joint nut castellations. Discard the old cotter pin.
3. 3

   Loosen ball joint nut
   Using a 15mm socket, loosen the ball joint nut but do not remove it completely. Leave the nut threaded on a few turns to protect the ball joint stud threads and prevent sudden separation when using the separator tool.
   ⚠Do not fully remove the nut before separating the joint to prevent sudden drop of suspension components.
4. 4

   Separate ball joint from knuckle
   Position the ball joint separator tool between the upper control arm and the knuckle. Apply steady pressure to separate the ball joint taper from the knuckle. Once the joint pops free, fully remove the ball joint nut and lift the control arm away from the knuckle.
5. 5

   Support suspension components
   Use a floor jack or suitable support under the lower control arm or axle to prevent excessive droop of the suspension once the upper control arm is removed. This prevents stress on brake lines and other components.
6. 6

   Remove front control arm mounting bolt
   Locate the front mounting bolt that secures the control arm to the frame bracket. Using an 18mm socket and breaker bar, remove the front control arm bolt completely. Note the orientation of any washers or spacers.
7. 7

   Remove rear control arm mounting bolt
   Using an 18mm socket and breaker bar, remove the rear control arm mounting bolt. The control arm can now be removed from the vehicle. Inspect the mounting points and bushings on the frame for wear or damage.
8. 8

   Clean mounting surfaces
   Use a wire brush to clean the ball joint taper seat in the knuckle and the control arm mounting points on the frame. Remove any corrosion, dirt, or old thread locker from bolt threads. Apply light penetrating oil if needed.
9. 9

   Install new upper control arm to frame
   Position the new upper control arm into the frame mounting brackets. Install both front and rear mounting bolts finger-tight only. Ensure any washers or spacers are in their correct positions. Do NOT torque these bolts yet.
   ⚠Control arm bolts must not be torqued until vehicle weight is on the wheels or bushing damage will occur.
10. 10

    Connect ball joint to knuckle
    Lift the control arm ball joint stud into the knuckle taper hole. Ensure the taper is seated properly and the stud protrudes through the knuckle sufficiently for the nut to thread on. Install the ball joint nut and torque to specification.
    Torque spec

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

    Install new cotter pin
    Install a new cotter pin through the ball joint nut castellations and the stud hole. If the cotter pin holes do not align, tighten the nut slightly (never loosen) until the next castellation aligns. Bend the cotter pin ends to secure.
12. 12

    Install wheel and lower vehicle
    Install the wheel and thread all lug nuts on by hand. Lower the vehicle slowly until the wheels just contact the ground but the vehicle weight is still partially on the jack stands. Torque lug nuts to specification in a star pattern.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)
13. 13

    Torque control arm bolts with vehicle weight loaded
    With the vehicle weight now on the wheels and suspension at normal ride height, torque both the front and rear upper control arm mounting bolts to specification. This ensures the bushings are in their neutral position.
    ℹ️Torquing control arm bolts at ride height is critical for bushing longevity. Do not skip this step.
    Torque spec

    Control Arm Bolts165 Nm (122 lb-ft)
14. 14

    Final lowering and verification
    Fully lower the vehicle to the ground and remove jack stands and floor jack. Bounce the rear suspension several times to settle all components. Perform a final verification of all fastener torque values.

Reassembly

1. Ensure cotter pin is properly installed and secured in ball joint nut
2. Verify all control arm mounting bolts were torqued at ride height, not with suspension hanging
3. Double-check wheel lug nut torque after first 50 miles of driving

Verification

• Visually inspect that the ball joint nut has a new cotter pin properly installed
• Verify there is no excessive play in the ball joint by attempting to move the top of the wheel in and out
• Test drive the vehicle at low speed and verify no unusual noises or handling issues from the rear suspension
• Perform a complete alignment check as suspension geometry has been altered; alignment is required after this repair

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