This procedure covers removal and replacement of the rear strut mount assembly on a 2021-2024 Ford F-150 with 3.5L EcoBoost engine, including safe suspension disassembly and reassembly with proper torque specifications.

Warnings

Tools required

Parts

• Rear strut mount assembly × 1 — Use OEM Ford specification
• Strut mount bearing (if not included) × 1 — Use OEM Ford specification

Preparation

1. Park vehicle on level, solid ground and engage parking brake
2. Chock the front wheels securely
3. Spray penetrating oil on rear strut mounting hardware and allow to soak
4. Loosen rear wheel lug nuts while vehicle is on ground (do not remove)
5. Raise rear of vehicle with floor jack at rear differential or frame rail
6. Support vehicle securely on jack stands placed at manufacturer-designated frame points
7. Remove rear wheel completely
8. Visually inspect the rear suspension for additional worn or damaged components

Procedure

1. 1

   Support the rear knuckle assembly
   Position a floor jack under the rear knuckle/control arm assembly with a block of wood to distribute load. Raise jack just enough to take slight tension off the strut but not to lift the vehicle. This maintains suspension geometry and prevents components from dropping when strut is disconnected.
   ⚠The jack must remain in place throughout strut removal to prevent sudden dropping of suspension components.
2. 2

   Access the upper strut mount from inside the vehicle
   For rear struts, access the upper mount nuts from inside the vehicle bed or cargo area. You may need to remove interior trim panels, carpet, or bed liner sections depending on your specific F-150 configuration. Locate the strut tower assembly - there will typically be 2-3 nuts visible at the top of the strut tower.
3. 3

   Remove upper strut mount nuts
   While supporting the strut from below with the floor jack, remove the upper strut tower nuts. On most F-150 configurations, there are three nuts securing the strut mount to the body. Hold the strut shaft from spinning if necessary (there should be a flat or hex feature at the top). Do not allow the strut assembly to drop.
   ⚠Ensure the floor jack is securely supporting the lower suspension before removing upper nuts.
4. 4

   Disconnect sway bar link if equipped
   If the sway bar link interferes with strut removal, disconnect it from the strut assembly. Hold the internal shaft with an Allen key to prevent spinning while loosening the nut. Remove the upper nut connecting the link to the strut.
   Torque spec

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

   Remove lower strut-to-knuckle bolts
   Locate the two bolts securing the bottom of the strut to the rear knuckle assembly. These are typically large bolts passing through the knuckle. Support the strut by hand or with an assistant while removing these bolts. The strut may be tight in the knuckle - use a brass drift or careful prying to separate if needed.
   ⚠Do not damage the knuckle bore or strut bracket during separation. Avoid using excessive force on aluminum components.
   Torque spec

   Strut-to-Knuckle Bolts140 Nm (104 lb-ft)
6. 6

   Remove strut assembly from vehicle
   Carefully lower the floor jack slightly to compress the suspension while pulling the bottom of the strut out of the knuckle. Once clear of the knuckle, maneuver the strut assembly down and out from the wheel well. You may need to angle the strut to clear brake lines and other components.
7. 7

   Inspect and replace strut mount
   With the strut removed, inspect the entire assembly. If only replacing the mount, you will need to disassemble the strut using spring compressors according to manufacturer safety procedures. Compress the spring evenly, remove the top nut, and replace the mount and bearing. If installing a complete strut assembly, proceed to reinstallation. Clean the strut tower mounting surface in the vehicle body with a wire brush.
   ⚠️Spring disassembly requires proper spring compressors and careful technique. Uncontrolled spring release can cause severe injury. If unfamiliar with this process, have a professional perform the work or purchase a complete strut assembly.
8. 8

   Install strut assembly into vehicle
   Maneuver the strut assembly (with new mount installed) up through the wheel well and into position. Align the upper mount studs with the holes in the strut tower. Install the upper mount nuts finger-tight but do not torque yet. Ensure the mount is properly seated and oriented correctly.
9. 9

   Connect strut to knuckle
   Raise the floor jack supporting the knuckle to align the strut bracket with the mounting holes in the knuckle. You may need to use a pry bar to align holes perfectly. Insert both strut-to-knuckle bolts and install nuts. Torque both bolts to specification.
   Torque spec

   Strut-to-Knuckle Bolts140 Nm (104 lb-ft)
10. 10

    Torque upper strut mount nuts
    Access the upper strut tower nuts from inside the vehicle. Torque all upper mount nuts to specification in a cross pattern to ensure even seating. Verify the mount is fully seated against the body and there are no gaps.
    Torque spec

    Strut Tower Nuts50 Nm (37 lb-ft)
11. 11

    Reconnect sway bar link if removed
    If the sway bar link was disconnected, reconnect it to the strut assembly. Install the nut and torque to specification while holding the internal shaft with an Allen key to prevent spinning.
    Torque spec

    Sway Bar Link71 Nm (52 lb-ft)
12. 12

    Reinstall wheel and lower vehicle
    Install the rear wheel and thread lug nuts by hand. Lower the vehicle carefully from jack stands until weight is on the wheels but vehicle is still slightly raised. Torque lug nuts to specification in a star pattern. Completely lower vehicle and remove jack.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)

Reassembly

1. Reinstall any interior trim panels, carpet, or bed liner sections that were removed for upper strut access
2. Verify all fasteners have been properly installed and torqued
3. Remove floor jack from under knuckle assembly
4. Double-check that no tools or parts were left in the wheel well or suspension area

Verification

• Bounce the rear corner of the vehicle several times to settle the suspension and verify proper operation with no unusual noises
• Perform a careful test drive at low speed in a safe area, listening for any abnormal sounds from the rear suspension
• Check for proper handling and that the vehicle tracks straight with no pulling
• After 50-100 miles of driving, re-torque the strut-to-knuckle bolts and wheel lug nuts to specification
• Have a front-end alignment performed by a professional shop, as suspension work can affect alignment settings

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