Torsion Bar

This procedure covers the removal and replacement of the front torsion bar adjustment bolt and key assembly on a 2011-2014 Ford F-150 3.5L EcoBoost 4WD, including proper ride height adjustment.

Warnings

Tools required

Parts

• Torsion bar adjustment bolt × 1 — Use OEM specification
• Torsion bar adjustment key × 1 — Use OEM specification
• Torsion bar adjustment nut × 1 — Use OEM specification

Preparation

1. Park vehicle on level, solid ground and set parking brake firmly
2. Chock rear wheels securely on both sides
3. Measure and record current front ride height from center of wheel hub to bottom of fender lip for reference
4. Mark the current position of the torsion bar adjustment bolt relative to the adjustment key with paint or marker
5. Count and record the number of threads visible on the adjustment bolt above the adjustment nut

Procedure

1. 1

   Raise and support vehicle
   Loosen front wheel lug nuts. Raise the front of the vehicle using a floor jack at the designated front jacking point. Support the vehicle on jack stands placed at the frame rails behind the front wheels. Remove the front wheel on the side being serviced. Allow the front suspension to hang freely without load.
2. 2

   Locate torsion bar adjustment components
   Locate the torsion bar adjustment bolt assembly at the rear of the lower control arm, just forward of the crossmember. The assembly consists of the adjustment bolt, adjustment key, and adjustment nut. Spray penetrating oil on the threads and allow to soak for 10-15 minutes if components appear corroded.
3. 3

   Relieve torsion bar tension
   Install the torsion bar unloading tool over the adjustment key and crossmember per tool manufacturer instructions. Carefully turn the tool to apply upward pressure on the adjustment key, relieving tension from the adjustment bolt. You will feel the load transfer to the tool. Apply only enough pressure to unload the bolt, approximately 1/4 to 1/2 inch of lift on the adjustment key.
   ⚠️Ensure the unloading tool is properly seated and secure before proceeding. The torsion bar is under extreme tension.
4. 4

   Remove adjustment bolt and key
   With tension relieved by the unloading tool, remove the adjustment nut from the adjustment bolt. Remove the adjustment bolt by turning it counterclockwise and withdrawing it from the adjustment key. Carefully release tension on the unloading tool gradually and evenly. Remove the unloading tool once tension is fully released. Slide the adjustment key off the torsion bar.
5. 5

   Inspect components
   Inspect the torsion bar splines, adjustment key, adjustment bolt threads, and adjustment nut for damage, excessive wear, or corrosion. The torsion bar itself should not be damaged, scored, or cracked. Clean all components with a wire brush, removing rust and debris from threads and mating surfaces.
6. 6

   Install new or cleaned adjustment key
   Slide the adjustment key (new or cleaned original) onto the torsion bar with the flat side facing toward the crossmember. Ensure the key is fully seated on the torsion bar splines and positioned in the crossmember slot.
7. 7

   Install unloading tool
   Reinstall the torsion bar unloading tool over the adjustment key and crossmember. Apply upward pressure to lift the adjustment key approximately 1/4 to 1/2 inch, creating clearance for the adjustment bolt installation.
8. 8

   Install adjustment bolt and nut
   Insert the new or cleaned adjustment bolt through the crossmember and into the adjustment key from the rear. Thread the adjustment nut onto the bolt finger-tight. Adjust the bolt to approximately the same position as marked during removal, matching the thread count recorded earlier.
9. 9

   Transfer suspension load
   Carefully and gradually release the unloading tool, transferring the torsion bar load back onto the adjustment bolt and key assembly. Ensure the adjustment key remains properly seated in the crossmember slot as tension is applied. Remove the unloading tool once load is fully transferred.
10. 10

    Reinstall wheel and lower vehicle
    Reinstall the front wheel and thread lug nuts on by hand. Lower the vehicle from jack stands using the floor jack until the tire just touches the ground but vehicle weight is still supported by jack stands. Torque wheel lug nuts to specification in a star pattern. Fully lower vehicle to the ground and remove jack and jack stands.
    Torque spec

    Wheel Lug Nuts156 Nm (115 lb-ft)
11. 11

    Adjust ride height
    With vehicle on level ground and at normal ride height, measure from center of wheel hub to bottom of fender lip. Compare to measurement recorded during preparation. Turn the adjustment bolt clockwise to increase ride height or counterclockwise to decrease ride height. Each full turn of the bolt changes ride height approximately 1/8 inch. Bounce the front suspension several times after each adjustment to settle the suspension before measuring.
12. 12

    Final adjustment verification
    Once desired ride height is achieved, ensure the adjustment nut is tightened securely against the crossmember. Verify both left and right side measurements are equal (within 1/4 inch). Road test the vehicle and recheck ride height measurements after 24 hours of normal driving, readjusting if necessary.

Reassembly

1. Ensure adjustment key remains fully seated on torsion bar splines throughout installation
2. Adjustment bolt should have equal thread engagement on both sides of the vehicle for balanced ride height
3. After final adjustment, verify suspension articulates freely without binding

Verification

• Measure ride height on both sides - should be within 1/4 inch of each other and match manufacturer specifications
• Drive vehicle over moderate bumps and verify normal suspension operation without clunking or binding
• Recheck ride height after 50-100 miles of driving and adjust if settled
• Inspect adjustment bolt area for proper seating and no signs of movement or loosening

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