Complete disassembly, inspection, and rebuild of the front differential assembly on a 2023 Rivian EDV 500, including bearing and seal replacement.

Warnings

Tools required

Parts

• Front differential bearing kit (includes pinion bearings, carrier bearings) × 1 — Use OEM specification
• Front differential seal kit (pinion seal, carrier seals) × 1 — Use OEM specification
• Ring gear bolts × 1 — Use OEM specification
• Pinion nut × 1 — Use OEM specification
• Differential gasket set × 1 — Use OEM specification
• Shim kit for pinion depth and bearing preload × 1 — Use OEM specification
• RTV silicone sealant (OEM approved) × 1 — Use OEM specification
• Thread locker (medium strength) × 1 — Use OEM specification

Fluids

• 75W-90 GL-5 Gear Oil — 2 qt

Preparation

1. Place vehicle on lift and raise to working height, ensuring proper support at manufacturer lift points
2. Disconnect 12V battery negative terminal and wait 5 minutes for system discharge
3. Follow manufacturer high-voltage isolation procedure and verify de-energization with appropriate meter
4. Place high-voltage safety lockout tag on service disconnect
5. Remove front wheels and tires
6. Remove front drive unit assembly from vehicle (see separate procedure if needed)
7. Clean exterior of differential housing thoroughly to prevent contamination during disassembly
8. Mount drive unit securely on workbench with appropriate fixtures
9. Drain differential fluid into appropriate container and dispose per local regulations
10. Photograph or document all electrical connector positions and routing before disconnection
11. Set up clean work area with parts trays for organized component storage

Procedure

1. 1

   Remove Front Drive Unit Components
   Disconnect and remove the electric motor assembly from the differential housing. Remove all electrical connectors from motor, noting their positions. Remove motor housing bolts in a cross-pattern to prevent warping. Carefully separate motor from differential housing, being careful not to damage any sealing surfaces. Set motor assembly aside in a safe location.
2. 2

   Mark and Remove Differential Bearing Caps
   Use a center punch or marker to clearly mark the bearing caps and housing for proper reassembly orientation. Remove bearing cap bolts and carefully remove bearing caps. Keep bearing caps with their respective bolts and shims. Note and record the position and thickness of any shims found behind bearing caps or races.
3. 3

   Remove Differential Carrier Assembly
   Carefully lift the differential carrier assembly (ring gear and case) out of the housing. If stuck, use a soft-face hammer to gently tap the carrier loose. Inspect the carrier bearings and races for wear, pitting, or damage. Place carrier assembly on clean work surface.
4. 4

   Remove Pinion Gear
   Mark the pinion nut position relative to pinion shaft for reference. Using a pinion holding tool or place carrier in position to lock pinion, remove pinion nut (note: this is a one-time use nut and must be replaced). Remove pinion flange using appropriate puller. Carefully drive or press pinion shaft out from rear of housing, catching it as it exits. Remove pinion front bearing, pinion rear bearing, and note all shim positions and thicknesses. Document pinion depth shim location and thickness.
5. 5

   Disassemble Differential Carrier
   Mark ring gear position relative to carrier before removal. Remove ring gear bolts (these are typically one-time use and should be replaced). Carefully separate ring gear from carrier using appropriate tools; avoid prying on gear teeth. Drive out carrier cross pin retaining pin. Remove cross pin, side gears, pinion gears, and thrust washers. Keep all components organized and inspect for wear.
6. 6

   Remove All Bearings and Races
   Using appropriate bearing pullers, remove carrier bearings from differential case. Remove pinion bearing races from housing using a slide hammer with race puller attachment or brass drift. Remove all seals from housing. Thoroughly clean all components in solvent and dry with compressed air. Inspect all gears for scoring, pitting, or abnormal wear patterns.
7. 7

   Inspect All Components
   Carefully inspect ring and pinion gears for wear patterns, scoring, or damage. Check all gear teeth for chips or cracks. Inspect differential case for cracks or wear. Check splines on side gears and pinion gears. Measure backlash clearances on side gears and pinion gears. Inspect housing for cracks or damage. Replace any worn or damaged components. Verify all new bearings and races are correct for application.
8. 8

   Install New Pinion Bearing Races
   Using bearing race drivers or a press, install new pinion front and rear bearing races into housing. Ensure races are fully seated and perpendicular to housing bores. Verify proper seating by checking that race is flush with housing shoulder around entire circumference.
9. 9

   Determine Pinion Depth
   Install pinion rear bearing on pinion shaft without shims initially. Using pinion depth gauge tool set, determine correct pinion depth shim thickness. Account for any variance markings on pinion head (typically +/- markings indicating deviation from nominal). Calculate and select appropriate shim thickness. Install selected shim on pinion shaft, then install rear bearing fully onto shaft using press or bearing installer.
10. 10

    Install Pinion Assembly
    Install new pinion seal in housing using seal driver. Lubricate pinion seal lip with gear oil. Install pinion front bearing on shaft. Insert pinion assembly through housing from rear, carefully guiding through seal. Install front bearing, collapsible spacer (or shims if used in this application), and pinion flange. Install new pinion nut and tighten gradually while checking pinion bearing rotating torque with inch-pound torque wrench. Target preload specification is critical - typically 15-25 in-lbs for new bearings. Do not overtighten; if preload is exceeded, disassembly and replacement of collapsible spacer is required.
11. 11

    Reassemble Differential Carrier
    Install thrust washers, pinion gears, and side gears into carrier. Install cross pin and verify proper alignment. Install cross pin retaining pin. Install ring gear on carrier in original marked position. Apply thread locker to new ring gear bolts. Install ring gear bolts and tighten in a cross-pattern in multiple stages to ensure even clamping and prevent warpage.
12. 12

    Install New Carrier Bearings and Set Preload
    Press new carrier bearings onto differential carrier, ensuring bearings are fully seated against carrier shoulders. Install carrier assembly into housing without shims initially. Using dial indicator, measure carrier movement to determine required shim thickness for proper bearing preload. Calculate shim requirements: add shims to eliminate end play, then add additional shims (typically 0.004-0.008 inches total) for bearing preload. Install appropriate shims behind bearing races.
13. 13

    Set and Check Ring and Pinion Backlash
    Install bearing caps in their original marked positions. Tighten bearing cap bolts in stages. Mount dial indicator to housing with plunger on ring gear tooth at 90 degrees to tooth face. Check backlash at 4 positions around ring gear (90 degrees apart). Backlash should be within specification (typically 0.004-0.008 inches) and should not vary more than 0.002 inches around the gear. If backlash is incorrect, adjust by moving shims from one side to the other: moving shims from ring gear side to opposite side increases backlash; moving shims toward ring gear decreases backlash.
14. 14

    Check Gear Contact Pattern
    Apply gear marking compound to several ring gear teeth. Rotate pinion through several revolutions in both directions while applying resistance. Examine tooth contact pattern. Pattern should be centered on tooth face with proper length and width. If pattern is incorrect, adjust pinion depth shims (toe/heel adjustment) or backlash shims (face/flank adjustment) as needed. Repeat pattern check until proper contact is achieved on both drive and coast sides.
15. 15

    Final Assembly and Seal Installation
    Once gear pattern is correct, remove bearing caps and apply a thin bead of RTV sealant to housing mating surfaces if required by design. Reinstall bearing caps and tighten bolts to specification in cross-pattern. Verify final backlash readings. Install motor housing using new gasket or RTV as specified. Tighten motor housing bolts in cross-pattern to specification. Install all seals and covers. Reconnect all electrical connectors in their original positions.

Reassembly

1. Reinstall front drive unit assembly into vehicle following reverse of removal procedure
2. Reconnect all drive axles and suspension components
3. Fill front differential with 1.5 quarts of 75W-90 GL-5 gear oil through fill port
4. Install fill plug and verify no leaks
5. Reconnect all electrical connections to drive unit
6. Remove high-voltage lockout tag and restore high-voltage system per manufacturer procedure
7. Reconnect 12V battery negative terminal
8. Install front wheels and tires

Verification

• Clear any diagnostic trouble codes using Rivian diagnostic software
• Perform electric drive system relearn/initialization procedure if required by manufacturer
• Conduct a test drive and verify smooth operation with no abnormal noises, vibrations, or binding
• Check for proper AWD engagement and torque distribution during acceleration
• Monitor differential temperature during test drive to verify it remains within normal range
• Re-check differential fluid level after test drive and top off if necessary
• Inspect for any fluid leaks around seals and gaskets
• Verify no new diagnostic trouble codes are present
• Document all shim sizes and measurements in service records for future reference

More procedures for this vehicle