Drive Pinion Shaft Assembly: Adjustment

1. Remove the liquid gasket from the mating surface completely.
2. Using the ST, install the drive pinion retainer to converter case.

   ST 18270KA020 SOCKET (E20)

   NOTE: Do not confuse the three different-length bolts when installing.

   Tightening torque: 

   43 N.m (4.4 kgf-m, 31.7 ft-lb) 

   Fig 1: Identifying Different-length Bolts

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3. Rotate the drive pinion several times using ST1 and ST2.

   ST1 18667AA010 HOLDER

   ST2 499787700 WRENCH

   Fig 2: Rotating Drive Pinion

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4. Adjust the drive pinion and hypoid driven gear backlash. Ref. to ADJUSTMENT , Front Differential Assembly.
5. Using the ST, remove the drive pinion retainer from converter case.

   ST 18270KA020 SOCKET (E20)

6. Apply lead-free red dye evenly on the both sides of three to four teeth of the hypoid driven gear. Then install the drive pinion retainer and rotate the drive pinion in both directions several times. Remove the drive pinion retainer and check the tooth contact pattern.

   If the teeth contact is inappropriate, adjust the backlash or thickness of the shim. Ref. to ADJUSTMENT , Front Differential Assembly.

   NOTE: After correction, wipe off the lead-free red dye.
   • Correct tooth contact

     Check item: Tooth contact surface is slightly shifted toward the toe side under a no-load condition. (When driving, it moves towards the heel side.) 

   Fig 3: Red Dye Application Location - Hypoid Driven Gear (Correct Tooth Contact)

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   • Face contact

     Check item: Backlash is too large  .

     Contact pattern

   Fig 4: Identifying Tooth Contact Pattern

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   Corrective action: Increase thickness of pinion height adjusting washer according to the procedure for bringing drive pinion close to hypoid driven gear side.

   Fig 5: Adjusting Pinion Height

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   • Flank contact

     Check item: Backlash is too small  .

     Contact pattern

   Fig 6: Identifying Flank Contact Pattern

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   Corrective action: Reduce the thickness of pinion height adjusting washer according to the procedure for bringing drive pinion away from hypoid driven gear.

   Fig 7: Reducing Thickness Of Pinion Height

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   • Toe contact (inside contact)

     Check item: Teeth contact area is too small  .

     Contact pattern

   Fig 8: Toe Contact Pattern (Inside Contact)

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   Corrective action: Reduce the thickness of pinion height adjusting washer according to the procedure for bringing drive pinion away from hypoid driven gear side.

   Fig 9: Bringing Drive Pinion Away From Hypoid Driven Gear Side

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   • Heel contact (outside end contact)

     Check item: Teeth contact area is too small  .

     Contact pattern

   Fig 10: Heel Contact Pattern (Outside End Contact)

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   Corrective action: Increase the thickness of the pinion height adjusting washer according to the procedures for moving the drive pinion closer to the hypoid driven gear.

   Fig 11: Moving Drive Pinion Closer To Hypoid Driven Gear

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7. If tooth contact is correct, mark the differential side retainer position and loosen. After fitting a new O-ring and oil seal, screw in the differential side retainer to the marked position.
8. Tighten the lock plate with specified torque.

   Tightening torque: 

25 N.m (2.5 kgf-m, 18.4 ft-lb) 

Fig 12: Identifying Lock Plate Bolt

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