Rear Differential: Disassembly

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

• Tooth contact and backlash between hypoid driven gear and drive pinion
• Hypoid driven gear runout on its back surface
• Total preload of drive pinion

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

   ST 398217700 ATTACHMENT

   Fig 1: Identifying Special Tool

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2. Remove the oil drain plug and filler plug, and drain the gear oil.
3. Remove the air breather cap.
   NOTE:

   • Do not attempt to replace the air breather cap unless necessary.
   • Whenever the air breather cap is removed, replace it with a new part.
   Fig 2: Identifying Air Breather Cap And Rear Cover

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4. Remove the bolts, and then remove the rear cover.
5. Keep the side bearing retainers separate to make it possible to identify RH and LH sides. Remove the side bearing retainer attaching bolts, set the ST to differential case, and extract the side bearing retainers RH and LH with a puller.
   NOTE: Each shim, which is installed to adjusted the side bearing preload, should be kept together with its mating retainer.

   ST 398457700 ATTACHMENT

   Fig 3: Identifying Special Tool

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6. Pull out the differential case assembly from differential carrier.
   NOTE: Be careful so that the teeth do not hit against the case.
   Fig 4: Pulling Out Differential Case Assembly

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7. When replacing the side bearing, remove the bearing cup from the side bearing retainer using ST.

   ST 398527700 PULLER ASSY

   Fig 5: Identifying Special Tool

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8. Remove the bearing cone with ST.
   NOTE:

   • Do not attempt to disassemble the parts unless necessary.
   • Set the puller so that its claws catch the edge of the bearing cone.
   • Never mix up the RH and LH bearing races and cones.

   ST 18759AA000 PULLER ASSY

   Fig 6: Identifying Special Tool

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9. Remove the hypoid driven gear by loosening hypoid driven gear bolts.
   Fig 7: Removing Hypoid Driven Gear Bolts

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10. Drive out the pinion shaft lock pin from the hypoid driven gear side.
    NOTE: The lock pin is staked at the pin hole end on the differential carrier. Do not drive it out forcibly before removing the stake.

    ST 899904100 STRAIGHT PIN REMOVER

    Fig 8: Identifying Special Tool

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11. Draw out the pinion mate shaft and remove pinion mate gears, side gears and thrust washers.
    NOTE: The gears should be marked or kept separated right and left, and front and rear as well as thrust washers.
    Fig 9: Identifying Differential Components

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12. Remove the self-locking nut while holding the companion flange with ST.

    ST 498427200 FLANGE WRENCH

    Fig 10: Removing Self-Locking Nut

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13. Extract the companion flange with a puller.
    Fig 11: 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, pinion height adjusting washer and washer.
    NOTE: Hold the drive pinion so as not to drop it.

    ST 398467700 DRIFT

    Fig 12: Identifying Special Tool

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

    ST 398517700 REPLACER

    Fig 13: Removing Rear Bearing Cone

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

    ST 398527700 PULLER ASSY

    Fig 14: Identifying Front Oil Seal And Differential Carrier

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17. Remove the pilot bearing together with the front bearing cone and spacer using the ST.

    ST 398467700 DRIFT

    Fig 15: Identifying Special Tools

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18. When replacing the bearings, hit out the front bearing cup and rear bearing cup in this order using a brass bar.

Fig 16: Tapping Alternately With Brass Bar

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