This procedure covers the complete removal and replacement of the rear differential assembly on a 2021-2024 Ford F-150 with 3.5L EcoBoost engine and rear-wheel drive configuration.

Warnings

Tools required

Parts

• Differential cover gasket × 1 — Use OEM specification
• Differential fill plug washer × 1 — Use OEM specification
• Driveshaft u-joint strap bolts (if reusing straps) × 4 — Use OEM specification
• Shop towels × 1 — Generic

Fluids

• Motorcraft 75W-140 Synthetic Gear Oil — 2.5 qt

Preparation

1. Park vehicle on level surface and engage parking brake
2. Chock front wheels securely
3. Raise rear of vehicle and support on jack stands at frame contact points
4. Remove both rear wheels
5. Place drain pan under differential
6. Allow differential to cool if vehicle was recently driven

Procedure

1. 1

   Drain differential fluid
   Remove the differential cover bolts in a crisscross pattern, loosening gradually to control fluid drainage. Once all bolts are loose, carefully pry the cover away and allow fluid to drain completely into the drain pan. Remove and inspect the cover gasket.
2. 2

   Mark driveshaft alignment
   Using marking paint or chalk, mark the relationship between the driveshaft and the differential pinion yoke. This ensures proper driveshaft phasing upon reassembly and prevents vibration issues.
3. 3

   Disconnect driveshaft
   Remove the four driveshaft bolts or u-joint strap bolts connecting the driveshaft to the rear differential pinion yoke. Support the driveshaft and carefully slide it rearward to separate it from the yoke. Secure the driveshaft out of the way using wire or a strap to prevent it from hanging.
   Torque spec

   Driveshaft Bolts85 Nm (63 lb-ft)

   Driveshaft U-Joint Straps20 Nm (15 lb-ft)
4. 4

   Disconnect axle shafts
   If equipped with independent rear suspension, remove the CV joint bolts connecting the axle shafts to the differential stub shafts. If equipped with solid axle, the axle shafts will remain with the differential assembly. Support the axle shafts to prevent damage to CV boots or joints.
   Torque spec

   CV Bolts70 Nm (52 lb-ft)

   CV Joint Bolts71 Nm (52 lb-ft)
5. 5

   Disconnect brake components and ABS wiring
   Disconnect the rear brake hoses from their mounting points on the differential housing or axle tubes. Disconnect any ABS wheel speed sensor wiring attached to the differential or axle assembly. Label connections for proper reassembly.
6. 6

   Position transmission jack
   Position a transmission jack or differential jack under the center of the differential housing. Adjust the jack to make light contact with the housing and secure with a chain or strap. The differential should be supported but not lifted at this point.
7. 7

   Remove differential mounting bolts
   Locate and remove all differential mounting bolts connecting the differential housing to the subframe or suspension components. On RWD F-150s, there are typically front and rear mounting bolts. Remove these bolts while supporting the differential with the transmission jack.
   Torque spec

   Mounting Bolts31 Nm (23 lb-ft)
8. 8

   Lower and remove differential
   Carefully lower the transmission jack while guiding the differential assembly away from the vehicle. Watch for any remaining electrical connections, brake lines, or vent hoses. The assembly is heavy and may require slight tilting or rotation to clear the frame and suspension components. Have an assistant help guide the unit out.
9. 9

   Inspect and prepare replacement differential
   If installing a replacement or rebuilt differential, transfer any necessary components such as mounting brackets, ABS tone rings, or axle stub shafts. Verify the gear ratio matches the original unit. Clean all mounting surfaces on the vehicle frame and suspension where the differential mounts.
10. 10

    Install differential assembly
    Using the transmission jack, carefully lift the differential into position. Align all mounting points with the frame and suspension brackets. Guide any wiring, vent hoses, and brake line mounting points into their proper positions. Install all mounting bolts finger-tight initially.
    Torque spec

    Mounting Bolts31 Nm (23 lb-ft)
11. 11

    Reconnect axle shafts
    Reconnect the axle shafts to the differential. For IRS-equipped vehicles, align the CV joint bolt holes and install new bolts if recommended. Ensure the CV joints are fully seated before tightening bolts in a crisscross pattern.
    Torque spec

    CV Bolts70 Nm (52 lb-ft)

    CV Joint Bolts71 Nm (52 lb-ft)
12. 12

    Reconnect driveshaft
    Align the driveshaft with the differential pinion yoke using the alignment marks made during disassembly. Install the driveshaft bolts or u-joint strap bolts. Tighten u-joint straps evenly to prevent binding. Rotate the driveshaft by hand to verify smooth rotation.
    Torque spec

    Driveshaft Bolts85 Nm (63 lb-ft)

    Driveshaft U-Joint Straps20 Nm (15 lb-ft)
13. 13

    Reconnect brake and ABS components
    Reconnect all brake hoses to their mounting points on the differential or axle tubes. Reconnect ABS wheel speed sensor wiring. Ensure all clips and retainers are properly secured and no wires are pinched or stretched.
14. 14

    Install differential cover
    Clean the differential cover and housing mating surfaces thoroughly with a gasket scraper and wire brush. Install a new differential cover gasket. Position the cover and install all cover bolts, tightening in a crisscross pattern to ensure even gasket compression and prevent leaks.
    Torque spec

    Differential Cover Bolts35 Nm (26 lb-ft)
15. 15

    Fill differential with gear oil
    Locate the differential fill plug on the side or front of the housing. Remove the fill plug and washer. Using a fluid pump or fill bottle, add Motorcraft 75W-140 Synthetic Gear Oil until it begins to drip from the fill hole. Install a new fill plug washer and reinstall the plug. The capacity is approximately 2.0 quarts but fill to the proper level.

Reassembly

1. Reinstall rear wheels and torque lug nuts in a star pattern to specification
2. Lower vehicle from jack stands
3. If brake lines were disconnected, bleed the brake system and verify proper pedal feel
4. Check for any fluid leaks around the differential cover and fill plug

Verification

• Test drive the vehicle at low speed and verify smooth operation with no unusual noises, vibrations, or binding
• Check for leaks around differential cover, fill plug, and axle seals after test drive
• Re-check differential fluid level after test drive and top off if necessary
• Verify proper operation of ABS system if wheel speed sensors were disturbed
• Check that parking brake functions correctly
• After 50-100 miles of driving, re-inspect all fasteners and fluid level

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