Ring and Pinion

This procedure covers the replacement of the ring and pinion gears in the rear differential of a 2011-2014 Ford F-150 with 5.0L V8 Coyote engine and 4WD, including proper setup of bearing preload and gear pattern verification.

Warnings

Tools required

Parts

• Ring and pinion gear set with setup shims × 1 — Match existing gear ratio or desired ratio
• Pinion bearing kit (front and rear bearings with races) × 1 — Use OEM or quality aftermarket
• Carrier bearing set (side bearings) × 1 — Use OEM specification
• Pinion seal × 1 — Use OEM specification
• Differential cover gasket × 1 — Use OEM or RTV gasket maker
• Crush sleeve or solid pinion spacer × 1 — Verify application - crush sleeve is OEM
• Pinion nut × 1 — Use new fastener
• Ring gear bolts × 10 — Use new Grade 8 or OEM bolts
• Marking compound × 1 — Gear pattern checking compound

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 rails
4. Remove both rear wheels using proper lift points
5. Place drain pan under rear differential
6. Mark driveshaft and pinion flange orientation for reinstallation alignment
7. Take reference photos of differential assembly before disassembly

Procedure

1. 1

   Remove driveshaft and drain differential
   Remove the four driveshaft U-joint strap bolts at the rear pinion flange. Support driveshaft and slide it rearward to separate from pinion yoke. Secure driveshaft out of the way. Remove differential cover bolts and carefully pry cover off. Drain gear oil completely into drain pan. Clean cover and housing mating surfaces thoroughly.
   Torque spec

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

   Differential Cover Bolts35 Nm (26 lb-ft)
2. 2

   Remove axle shafts
   Remove the axle shaft retaining nuts at the wheel hubs (these are the large center nuts). Remove the CV shaft-to-differential bolts on both sides (6 bolts per side). Carefully pull both axle assemblies outward from the differential housing and set aside on clean surface. Cap or plug the differential side openings to prevent contamination.
   ⚠Axle nuts require significant torque to remove. Use breaker bar or impact gun. Do not reuse axle nuts.
   Torque spec

   Axle Nut250 Nm (184 lb-ft)

   CV Bolts76 Nm (56 lb-ft)
3. 3

   Remove pinion flange and measure preload
   Using an inch-pound torque wrench on the pinion nut, measure and record the rotational torque required to turn the pinion (pinion bearing preload). This should be 16-29 inch-pounds for used bearings. Using pinion holding tool, remove pinion nut. Mark the pinion flange position relative to pinion shaft. Use appropriate puller to remove pinion flange. Remove pinion seal and set aside.
   ℹ️Recording original preload helps verify proper reassembly. New bearings will require higher preload than used bearings.
4. 4

   Remove carrier assembly
   Mark the differential bearing caps with identification marks showing their orientation (driver/passenger and forward direction). Remove carrier bearing cap bolts. Install case spreader tool on differential housing following manufacturer instructions. Carefully spread case only enough to remove carrier (maximum 0.020 inch spread). Pry carrier assembly out of housing. Remove case spreader immediately to prevent housing distortion. Remove and keep carrier bearing shims for reference.
   ⚠️Over-spreading the differential case can permanently damage the housing. Never exceed 0.020 inch spread and never leave spreader installed longer than necessary.
5. 5

   Remove pinion from housing
   Tap pinion shaft rearward through the housing and remove from front. Remove pinion rear bearing, crush sleeve (or solid spacer), front bearing, and shim pack. Keep shim pack together for reference. Note and record thickness of original pinion depth shim. Using bearing race driver, remove front and rear pinion bearing races from housing. Measure and record race bore depth for reference.
6. 6

   Disassemble carrier and remove old ring gear
   Using bearing puller, remove carrier side bearings from differential case. Mark ring gear orientation to carrier. Remove ring gear bolts (typically left-hand thread). Use soft mallet to separate ring gear from carrier if needed. Clean carrier thoroughly and inspect for wear or damage. Clean ring gear mounting surface on carrier completely.
   ⚠Ring gear bolts are often left-hand thread. Turn clockwise to loosen. Verify thread direction before applying force.
7. 7

   Install new pinion races and determine pinion depth
   Using bearing race driver, install new front and rear pinion bearing races into housing, ensuring they are fully seated. Using pinion depth gauge tool set, determine correct pinion depth shim thickness. The pinion head is marked with a variance number (typically +1 to -4). Calculate required shim thickness based on gauge reading and pinion variance marking. Install calculated shim on pinion shaft.
   ℹ️Pinion depth is critical for proper gear contact pattern. The variance number on pinion head must be factored into shim calculation. Consult gear manufacturer specifications.
8. 8

   Assemble and install pinion
   Press front pinion bearing onto pinion shaft. Install depth shim, then install pinion into housing from front. Install rear pinion bearing onto shaft. Install new crush sleeve (or solid spacer with calculated preload shim if using eliminators). Install pinion flange, aligning reference marks if reusing original flange. Install new pinion nut hand-tight.
9. 9

   Set pinion bearing preload
   Using pinion holding tool and torque wrench, tighten pinion nut gradually while checking rotational torque with inch-pound torque wrench. Target preload is 16-29 inch-pounds for used bearings, or 20-35 inch-pounds for new bearings. Tighten pinion nut in small increments, checking preload frequently. Once preload is achieved, do not loosen nut - if preload is exceeded, crush sleeve must be replaced and process restarted.
   ⚠️Never back off pinion nut to reduce preload when using crush sleeve. This will require complete disassembly and new crush sleeve installation. Always approach target preload slowly.
10. 10

    Install ring gear on carrier
    Clean and inspect new ring gear. Align ring gear on carrier, ensuring proper orientation and alignment of bolt holes. Install new ring gear bolts with thread locker. Tighten ring gear bolts in star pattern to 70-90 lb-ft in three stages: first to 30 lb-ft, then 60 lb-ft, then final torque. Verify ring gear is seated flush against carrier.
11. 11

    Install carrier bearings and determine backlash
    Press new carrier side bearings onto differential case. Install carrier into housing without shims initially. Install case spreader and spread housing slightly. Install carrier bearing caps in original orientation with identifying marks aligned. Using dial indicator on ring gear tooth, measure side-to-side movement. Remove carrier and install shims to achieve 0.006-0.010 inch backlash. Equal shims both sides for initial setup.
12. 12

    Set final backlash and check pattern
    Install case spreader and install carrier with calculated shims. Install bearing caps and torque cap bolts to 55-65 lb-ft. Remove case spreader. Mount dial indicator on housing with plunger against ring gear tooth. Rock ring gear back and forth and measure backlash. Target is 0.006-0.010 inch. Adjust by moving shim thickness from one side to other (adding to one side, subtracting equal amount from other maintains bearing preload while changing backlash). Apply gear marking compound to several ring gear teeth. Rotate pinion through several revolutions in both directions while applying resistance to carrier. Examine contact pattern on ring gear teeth.
    ℹ️Proper gear contact pattern should be centered on tooth face with elongated oval pattern. Pattern adjustments require changing pinion depth shims or backlash shims. Consult gear setup guide for pattern interpretation.
13. 13

    Install pinion seal and final assembly
    Clean pinion flange sealing surface. Install new pinion seal using seal driver, ensuring seal is square and seated to proper depth. Verify pinion preload has not changed during carrier installation. If preload is below specification, pinion nut may need slight additional tightening. Install new differential cover gasket or apply RTV gasket maker in continuous bead. Install differential cover and torque bolts in criss-cross pattern.
    Torque spec

    Differential Cover Bolts35 Nm (26 lb-ft)
14. 14

    Reinstall axles and driveshaft
    Remove plugs from differential side outputs. Carefully insert both CV axle assemblies into differential, ensuring splines engage properly. Install CV bolts and torque to specification in star pattern. Install new axle shaft nuts and torque to specification. Install new cotter pins or stake nuts as applicable. Install driveshaft to pinion flange, aligning reference marks made during disassembly. Install U-joint strap bolts and torque evenly.
    Torque spec

    CV Bolts76 Nm (56 lb-ft)

    Axle Nut250 Nm (184 lb-ft)

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

    Fill differential and test
    Fill differential with Motorcraft 75W-140 Synthetic Gear Oil through fill hole until oil reaches bottom of fill hole (approximately 2.5 quarts). Install fill plug. Install rear wheels and torque lug nuts in star pattern. Lower vehicle. Test drive vehicle at various speeds, listening for abnormal noise. Check for leaks at pinion seal and cover. Re-check gear oil level after test drive and top off if needed.
    ⚠New gears require 500-mile break-in period. Avoid heavy acceleration, towing, or sustained highway speeds during break-in. Change gear oil after break-in period.
    Torque spec

    Wheel Lug Nuts140 Nm (103 lb-ft)

Reassembly

1. Verify all torque specifications are met, particularly axle nuts, CV bolts, and differential cover bolts
2. Ensure driveshaft is aligned properly with reference marks to prevent vibration
3. Double-check differential fluid level after test drive - low fluid will cause immediate gear damage
4. Verify no leaks at pinion seal or differential cover after test drive

Verification

• Test drive vehicle and verify smooth operation with no whining, howling, or clunking noises from rear axle
• Check for vibration at all speeds - vibration may indicate driveshaft misalignment
• Verify no leaks from pinion seal or differential cover gasket
• Confirm proper gear engagement in forward and reverse with no binding or noise
• Re-torque wheel lug nuts after 50-100 miles
• Change differential fluid after 500-mile break-in period and inspect for metal particles on drain plug magnet

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