2015–2026 Ford F-150 Rear Lowering Shackles

Installation Guide | Apoc Industries | SKUs: 7-322 (2"), 7-323 (1.75"), 7-324 (1.5") | Drop Range: 1.5"–2" | Bolt-On | Install Time: ~2 Hours | No Welding Required

Pre-Install Checklist

Required Tools

• Floor jack (minimum 2-ton capacity)
• Jack stands — minimum 2-ton rated, set of 4
• Torque wrench
• Socket set — metric and standard, 3/8" and 1/2" drive
• Grease gun compatible with 1/4"-28 zerk fittings
• Pry bar and rubber mallet
• Trim tool or angle grinder (for rear bed support trimming — 2" drop / SKU 7-322 only)
• Safety glasses, gloves, and steel-toed boots (PPE)

Vehicle Preparation

• Park vehicle on a flat, level, hard surface
• Engage parking brake fully
• Chock all four wheels before lifting
• Allow exhaust components to cool completely before working near the rear suspension

Safety Warnings

⚠ ALWAYS use rated jack stands — never work under a vehicle supported only by a floor jack. Wear safety glasses and gloves at all times. Keep bystanders clear of the work area. If installing the 2" drop (SKU 7-322), rear bed support trimming IS required — wear a face shield during this step.

Verify Fitment Before Starting

• Confirm vehicle year is 2015–2026 Ford F-150
• Confirm drivetrain — this kit fits both 2WD and 4WD models
• Confirm your SKU matches your desired drop height per the fitment table below

SKU / Drop Height Fitment Table

Parts Checklist

Verify all items against your packing slip before beginning installation.

• 2x Rear lowering shackles (driver and passenger side) — 1/4" thick steel, satin black powder coat
• Pre-installed PTMEG polyurethane bushings (replaceable)
• 1/4"-28 thread grease fittings (zerk fittings) — pre-installed
• Installation hardware (bolts included)

Step-by-Step Installation Sequence

Step 1 — Safety Setup and Vehicle Lift

• Complete all pre-install checklist items above
• Position floor jack under the vehicle's rear axle jack point
• Raise the rear of the vehicle to a safe working height and place jack stands under rated frame points
• Lower vehicle onto jack stands and confirm stability before proceeding
• Remove rear wheels and tires (optional but recommended for easier access)

Step 2 — Support the Rear Axle

• Place a floor jack under the rear axle to support it — do not allow the axle to hang unsupported once the leaf spring shackles are removed
• Lower the axle slightly to relieve tension on the factory shackles

Step 3 — Remove Factory Rear Shackles

• Locate the factory rear leaf spring shackles at the rear of each leaf spring pack (driver and passenger side)
• Remove the upper shackle bolt connecting the shackle to the leaf spring eye — retain hardware if reusing
• Remove the lower shackle bolt connecting the shackle to the frame mount
• Remove the factory shackle — factory shackles will not be reused
• Inspect the frame mount and leaf spring eye for wear or damage before proceeding

💡 Note on Upper Bolt Removal: Some customers report that cutting the upper shackle bolt is required for removal due to tight clearance at the leaf spring eye. However, this can be avoided without cutting. Two methods that work:

• Method 1 — Articulate the axle: Lower only one side of the rear axle at a time using your floor jack. Dropping one side articulates the axle enough to create clearance and allow the upper bolt to slide free.
• Method 2 — Pry bar: Use a pry bar to pry the rear of the leaf spring away from the frame hanger and downward just enough to create clearance to remove the upper bolt.

Either method eliminates the need to cut the bolt. Take your time and work one side at a time.

Step 4 — Trim Rear Bed Support (Required for 2" Drop / SKU 7-322 Only)

⚠ Note: Rear bed support trimming is only required when installing the 2" drop shackle (SKU 7-322). The 1.5" (SKU 7-324) and 1.75" (SKU 7-323) shackles clear the bed support without modification. If you are installing SKU 7-323 or 7-324, skip this step and proceed to Step 5.

For 2" drop (SKU 7-322) installers:

• With the factory shackle removed, identify the rear bed support that may contact the new lowering shackle at full droop
• Note: contact with the bed support occurs only at full suspension droop (e.g., when the vehicle is lifted for service) — at normal ride height the shackle remains clear
• Mark the area of the bed support that requires trimming for clearance
• Using a trim tool or angle grinder, carefully remove only the material necessary for clearance — do not remove structural material
• Deburr all trimmed edges and clean metal shavings from the area
• Wear a face shield during all trimming operations

Step 5 — Install New Lowering Shackles

• Position the new APOC lowering shackle at the frame mount and leaf spring eye — the longer shackle length provides the drop
• Install the lower shackle bolt through the frame mount and shackle — hand-tighten only at this stage
• Install the upper shackle bolt through the shackle and leaf spring eye — hand-tighten only at this stage
• Repeat on the opposite side
• Confirm both shackles are oriented correctly and seated fully before torquing

Step 6 — Torque All Fasteners

• Using a calibrated torque wrench, torque all shackle bolts to specification with the vehicle at ride height (suspension loaded)
• Mark all torqued fasteners with a torque stripe for visual verification

Torque Specifications:

• Lower shackle bolt (frame mount): 173 ft-lbs
• Upper shackle bolt (leaf spring eye): 173 ft-lbs

Note: If OEM torque specs for your specific year are available in your factory service manual, defer to those values.

Step 7 — Grease All Fittings (1/4"-28 Thread)

• Locate the 1/4"-28 thread grease fittings (zerk fittings) on each shackle
• Using a grease gun, pump silicone grease into each fitting until grease purges from the bushing seal — use silicone grease only; petroleum-based grease will cause premature bushing failure
• Wipe away excess grease
• Confirm all fittings are seated and not cross-threaded

Step 8 — Lower Vehicle and Inspect

• Reinstall rear wheels and tires if removed — torque lug nuts to vehicle manufacturer specification
• Raise vehicle off jack stands, remove stands, and lower vehicle to the ground
• Bounce the rear suspension several times to settle the geometry
• Visually inspect both shackles and all hardware for proper seating
• Check that no components contact the frame, body, bed support, or brake lines through full suspension travel
• Verify the drop height matches your selected SKU

Step 9 — Road Test and Re-Check Torque After 50–100 Miles

• Perform an initial low-speed road test — listen for unusual noises and check for vibration or clunking
• After 50–100 break-in miles, re-torque all shackle fasteners to specification
• Re-grease all fittings after the break-in period — use silicone grease only
• Inspect all hardware for loosening or movement

Re-Torque Specifications (after 50–100 miles):

• Upper and lower shackle bolts: 173 ft-lbs

Post-Install Notes

• Actual drop amount may vary slightly depending on spring wear and vehicle load
• Bushings are replaceable — PTMEG polyurethane, no special tools required for replacement
• Inspect all hardware for loosening at each oil change interval
• Grease interval: Apply a couple pumps of silicone grease at every oil change — use silicone grease only, do not use petroleum-based grease

Safety Disclaimers

This installation guide is provided for reference purposes. Apoc Industries assumes no liability for improper installation, use of incorrect torque values, or failure to follow all safety procedures. Suspension modifications affect vehicle handling characteristics. Always have suspension work inspected by a qualified mechanic and comply with all local laws regarding vehicle modifications and ride height limits.

Apoc Industries | apocindustries.com | SKUs: 7-322, 7-323, 7-324 | Document Version: v1.0