Replacement of the front lower control arm on a 2015-2020 Ford F-150 3.5L EcoBoost, including ball joint separation and proper torque procedure at ride height.

Warnings

Tools required

Parts

• Front lower control arm assembly × 1 — Use OEM specification
• Ball joint castle nut (if not reusable) × 1 — Use OEM specification

Preparation

1. Park vehicle on level, solid ground and engage parking brake
2. Chock rear wheels securely
3. Loosen front wheel lug nuts 1/4 turn while vehicle is on ground
4. Raise front of vehicle with floor jack at designated jacking point
5. Support vehicle with jack stands under frame rails rated for vehicle weight
6. Remove front wheel completely
7. Spray all fasteners with penetrating oil and allow to soak for 15-30 minutes if corrosion is present
8. Inspect control arm, ball joint, and bushings for wear to confirm replacement is necessary

Procedure

1. 1

   Support the knuckle assembly
   Place a transmission jack or adjustable jack stand under the steering knuckle/brake assembly to support its weight once the control arm is disconnected. Adjust height so the suspension is at or near normal ride height position. This will relieve tension on the ball joint.
2. 2

   Remove the ball joint castle nut
   Remove the cotter pin from the ball joint castle nut if equipped. Using an 18mm socket, remove the castle nut from the lower ball joint stud. Keep the nut if it is in good condition and will be reused, otherwise discard.
3. 3

   Separate the ball joint from the knuckle
   Install a ball joint separator tool between the lower control arm and the steering knuckle. Tighten the separator to apply pressure, then strike the knuckle mounting area sharply with a hammer to shock the taper loose. Alternatively, use a pickle fork by driving it between the control arm and knuckle. The ball joint stud will pop free from the knuckle taper. Lower the jack slightly to allow clearance.
   ⚠Do not damage the ball joint boot or knuckle surface if reusing components. Pickle forks typically damage boots and should only be used when replacing the control arm.
4. 4

   Mark control arm position
   Before removing the control arm mounting bolts, mark the position of any alignment cams or shims if present. Take a photo for reference. On 2015-2020 F-150 models, the lower control arm uses fixed mounting points, but verify your specific configuration.
5. 5

   Remove rear control arm bolt
   Using a 21mm socket and breaker bar, remove the rear control arm-to-frame bolt. This bolt passes through the rear bushing. Support the control arm with your hand as you remove the bolt to prevent it from dropping. The bolt may be tight due to the bushing compression.
6. 6

   Remove front control arm bolt
   Using a 21mm socket and breaker bar, remove the front control arm-to-frame bolt. This bolt passes through the front bushing. Control the lower control arm as you remove the last bolt, as it may shift position once free.
   ⚠The control arm will be free to move once this bolt is removed. Maintain control to prevent it from falling or swinging.
7. 7

   Remove the lower control arm
   Maneuver the lower control arm out of the frame mounting points and remove it from the vehicle. Inspect the ball joint boot, bushings, and control arm for the source of wear. Clean the frame mounting points with a wire brush to remove any rust or debris.
8. 8

   Prepare the new control arm
   Unpack the new lower control arm and verify it matches the original. Inspect the ball joint boot for damage and ensure bushings are properly seated. Apply a thin film of anti-seize to the bolt threads (not the clamping surfaces). Position the new control arm into the frame mounts.
9. 9

   Install control arm bolts finger-tight
   Insert the front and rear control arm-to-frame bolts through the bushings and frame mounts. Thread the nuts onto the bolts by hand and tighten them finger-tight only. DO NOT torque these bolts yet - they must be torqued at ride height in a later step.
   ⚠️Do NOT torque the control arm-to-frame bolts at this time. These must be torqued at ride height to prevent bushing bind and premature failure.
10. 10

    Connect ball joint to knuckle
    Raise the transmission jack to lift the steering knuckle and align the ball joint stud with the hole in the knuckle. Insert the ball joint stud into the knuckle taper. Install the castle nut and tighten to the specified torque using an 18mm socket and torque wrench. Install a new cotter pin if equipped, ensuring it is properly secured.
    Torque spec

    Ball Joint Nut150 Nm (111 lb-ft)
11. 11

    Set suspension to ride height
    Using the transmission jack under the lower control arm or knuckle, carefully raise the suspension until it is at normal ride height position. This simulates the vehicle weight on the suspension. The suspension should be compressed to the same position as when the vehicle is resting on the ground. You may need to reference the opposite side for comparison if it has not been disassembled.
    ℹ️Ride height is critical for proper bushing alignment. The suspension should be loaded as if the vehicle weight is on the wheels.
12. 12

    Torque control arm-to-frame bolts at ride height
    With the suspension at ride height, torque the front and rear control arm-to-frame bolts to 300 Nm (222 lb-ft) using a torque wrench. This extremely high torque requires a quality torque wrench and may require significant effort. Verify both bolts are fully torqued. Lower the transmission jack.
    ⚠️These bolts require 300 Nm (222 lb-ft) and must be torqued at ride height. Use a properly calibrated torque wrench capable of this specification.
    Torque spec

    Control Arm-to-Frame Bolts300 Nm (222 lb-ft)
13. 13

    Reinstall wheel and lower vehicle
    Reinstall the wheel onto the hub, threading lug nuts by hand. Lower the vehicle until the tire just contacts the ground but the vehicle weight is still on jack stands. Torque the lug nuts to specification in a star pattern using a torque wrench. Fully lower the vehicle and remove jack stands. Torque lug nuts again on the ground to verify proper torque.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)

Reassembly

1. Ensure all fasteners are torqued to specification, particularly the control arm-to-frame bolts which were torqued at ride height
2. Verify the ball joint castle nut is properly torqued and cotter pin is installed if equipped
3. Double-check that all tools and parts have been removed from the work area

Verification

• Bounce the front end of the vehicle several times and listen for any unusual noises from the control arm area
• Perform a visual inspection underneath to verify all bolts are tight and properly installed
• Test drive the vehicle at low speed in a safe area, checking for any pulling, vibration, or unusual handling
• Have a professional alignment performed immediately, as control arm replacement affects camber and caster angles
• After 50-100 miles of driving, re-check all fastener torques to ensure nothing has loosened

More procedures for this vehicle