Rear Differential: Disassembly

To detect real cause of trouble, inspect the following items before disassembling.

• Tooth contact of crown gear and pinion, and backlash
• Runout of crown gear at its back surface
• Turning resistance of drive pinion

1. Set ST on vise and install the differential assembly to ST.

   ST 398217700 ATTACHMENT SET

   Fig 1: Installing Differential Assembly To ST

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2. Drain gear oil by removing plug.
3. Remove the air breather cap.
   NOTE: Do not attempt to replace the air breather cap unless necessary.
   Fig 2: Removing Air Breather Cap

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4. Remove rear cover by loosening retaining bolts.
   Fig 3: Removing Rear Cover By Loosening Retaining Bolts

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5. Make right and left side bearing retainers in order to identify them at reassembly. Remove side bearing retainer attaching bolts, set ST to differential case, and extract right and left side bearing retainers with a puller.
   NOTE: Each shim, which is installed to adjust the side bearing preload, should be kept together with its mating retainer.

   ST 398457700 ATTACHMENT

   Fig 4: Removing Side Bearing Retainer Attaching Bolts

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6. Pull out differential case assembly from differential carrier.
   NOTE: Be careful not to hit the teeth against the case.
   Fig 5: Pulling Out Differential Case Assembly From Differential Carrier

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7. When replacing side bearing, pull bearing cup from side bearing retainer using ST. ST 398527700 PULLER ASSY
   Fig 6: Pulling Bearing Cup From Side Bearing Retainer Using ST

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8. Extract bearing cone with ST.
   CAUTION: Do not attempt to disassemble the parts unless necessary. 
   NOTE:

   • Set puller so that its claws catch the edge of the bearing cone.
   • Never mix up the right and left hand bearing races and cones.

   ST 399527700 PULLER SET

   Fig 7: Setting Puller To Claws Catch Edge Of Bearing Cone

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9. Remove crown gear by loosening crown gear bolts.
   CAUTION: Further disassembling is not allowed. 
   Fig 8: Removing Crown Gear By Loosening Crown Gear Bolts

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10. Drive out pinion shaft lock pin from crown gear side.
    NOTE: The lock pin is staked at the pin hole end on the differential carrier; do not drive it out forcibly before unstaking it.

    ST 899904100 STRAIGHT PIN REMOVER

    Fig 9: Removing Straight Pin

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11. Draw out pinion mate shaft and remove pinion mate gears, side gears and thrust washers.
    NOTE: The gears as well as thrust washers should be marked or kept separated left and right, and front and rear.
    Fig 10: Removing Pinion Mate Gears, Side Gears & Thrust Washers

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12. Hold companion flange with ST and remove drive pinion nut.

    ST 498427200 FLANGE WRENCH

    Fig 11: Removing Drive Pinion Nut

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13. Extract the companion flange with a puller.
    Fig 12: Extracting Companion Flange With Puller

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14. Press the end of drive pinion shaft and extract it together with rear bearing cone, preload adjusting spacer and washer.
    NOTE: Hold the drive pinion so as not to drop it.

    ST 398467700 DRIFT

    Fig 13: Pressing End Of Drive Pinion Shaft

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15. Remove rear bearing cone from drive pinion by supporting cone with ST.
    NOTE: Place the replacer so that its center-recessed side faces the pinion gear.

    ST 398517700 REPLACER

    Fig 14: Removing Rear Bearing Cone From Drive Pinion

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16. Remove front oil seal from differential carrier using ST.

    ST 398527700 PULLER ASSY

    Fig 15: Removing Front Oil Seal From Differential Carrier

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17. Remove pilot bearing together with front bearing cone using ST.

    ST 398467700 DRIFT

    Fig 16: Removing Pilot Bearing Together With Front Bearing Cone

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18. When replacing bearings, tap front bearing cup and rear bearing cup in this order out of case by using a brass bar.
    Fig 17: Tapping Front Bearing Cup & Rear Bearing Cup

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