Rear Differential: Assembly

1. Press the rear bearing race (rear) into differential carrier using ST1 and ST2.

   ST1 398477701 HANDLE

   ST2 398477703 DRIFT 2

   Fig 2: Pressing Rear Bearing Race (Rear) Into Differential Carrier

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2. Using ST1 and ST2, install the rear bearing race (front) to differential carrier.

   ST1 398477701 HANDLE

   ST2 398477702 DRIFT

3. Insert the ST1 into carrier with pinion height adjusting washer and rear bearing cone fitted onto it.
   NOTE:

   • Re-use the used washer if not deformed.
   • Use a new rear bearing cone.
4. Then install the preload adjusting spacer and washer, front bearing cone, ST2, companion flange, and washer and drive pinion nut.

   ST1 398507702 DUMMY SHAFT

   ST2 398507703 DUMMY COLLAR

   Fig 3: Installing Preload Adjusting Spacer & Washer

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5. Turn the ST1 with hand to make it seated, and tighten the drive pinion nut while measuring the preload with spring balance. Select the preload adjusting washer and spacer so that the specified preload is obtained when nut is tightened to the specified torque.

ST1 398507704 BLOCK

ST2 398507702 DUMMY SHAFT

1. Tightening torque:  181 N.m (18.5 kgf-m, 134 ft-lb)

Fig 4: Locking ST2 With ST1

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Fig 5: Front & Rear Bearing Preload Specification Chart

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Fig 6: Measuring Front & Rear Bearing Preload

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Fig 7: Preload Adjusting Washer & Spacer Specification Chart

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Adjust the drive pinion height with shim installed between the rear bearing cone and back of pinion gear.

1. Do not remove the ST1, ST2 and ST3 out of position after adjusting pinion bearing preload in previous step.
   NOTE: At this time, install a pinion height adjusting shim which is temporarily selected or the same as that used before. Measure and record the thickness.

   ST1 398507702 DUMMY SHAFT

   ST2 398507701 DIFFERENTIAL CARRIER GAUGE

   ST3 398507703 DUMMY COLLAR

   Fig 8: Installing Pinion Height Adjusting Shim

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2. Measure the clearance N between the end of ST2 and end surface of ST1 by using a thickness gauge.
   NOTE: Make sure there is no clearance between the case and ST2.

   ST1 398507702 DUMMY SHAFT

   ST2 398507701 DIFFERENTIAL CARRIER GAUGE

   Fig 9: Measuring Clearance N Between End Of ST2 & End Surface Of ST1

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3. Obtain the thickness of pinion height adjusting shim to be inserted from the following formula, and replace the temporarily installed shim with this one.
   1. T = To + N - (H x 0.01) - 0.20 mm (0.0079 in)

Fig 10: Thickness Specification Chart

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(Example of calculation) 

1. To = 2.20 + 1.20 = 3.40 mm
2. N = 0.23 mm
3. H = +1
4. T = 3.40 + 0.23 - 0.01 - 0.20 = 3.42
5. Result: Thickness = 3.42 mm

   Therefore use the shim 383605200.

   Fig 11: Pinion Height Adjusting Shim Chart (1 Of 2)

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   Fig 12: Pinion Height Adjusting Shim Chart (2 Of 2)

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ST 398177700 INSTALLER

Fig 13: Installing Selected Pinion Height Adjusting Shim On Drive Pinion

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ST1, ST2 and ST3.

ST1 398507703 DUMMY COLLAR

ST2 399780104 WEIGHT

ST3 899580100 INSTALLER

Fig 15: Press-Fitting Front Bearing Cone Into Case

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ST1 399780104 WEIGHT

ST2 899580100 INSTALLER

Fig 16: Press-Fitting Pilot Bearing

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ST 498447120 DRIFT

Fig 17: Fitting Oil Seal

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ST1 899874100 INSTALLER

ST2 399780104 WEIGHT

Fig 18: Press-Fitting Companion Flange

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ST 498427200 FLANGE WRENCH

1. Tightening torque:  181.5 N.m (18.5 kgf-m, 133.8 ft-lb)

Fig 19: Installing Self-Locking Nut

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Install the side gears and pinion mate gears, with their thrust washers and pinion mate shaft, into differential case. (Without LSD)

Fig 20: Assembling Differential Case

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1. Measure the side gear backlash.
   1. Side gear back clearance:  0.10 - 0.20 mm (0.0039 - 0.0079 in)
   Fig 21: Measuring Side Gear Backlash

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2. Adjust the backlash as specified by selecting the side gear thrust washer.
   Fig 22: Side Gear Thrust Washer Specification Chart

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3. Check the condition of rotation after applying oil to the gear tooth surfaces and thrust surfaces.
4. After inserting the pinion shaft lock pin into differential case, stake both sides of the hole to prevent pin from falling off.

1. Lock Tite:  THREE BOND 1324 (Part number: 004403042) or equivalent

1. Tightening torque:  103 N.m (10.5 kgf-m, 75.9 ft-lb)

Fig 23: Installing Crown Gear On Differential Case

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ST 398237700 DRIFT

Fig 24: Pressing Side Bearing Onto Differential Case With ST

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ST 398487700 DRIFT

1. The driven gear backlash and side bearing preload can be determined by the side bearing retainer shim thickness.
2. Install the differential case assembly into differential carrier in the reverse order of disassembly.
   Fig 25: Installing Differential Case Assembly Into Differential Carrier

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3. Install the side retainer shims to the right and left retainers from which they were removed.
   NOTE: Replace the broken or corroded side retainer shim with a new one of same thickness.
   Fig 26: Side Bearing Retainer Shim Specification Chart

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4. Align the arrow mark on differential carrier with the mark on side retainer during installation.
   Fig 27: Aligning Arrow Mark On Differential Carrier With Mark On Side Retainer

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5. Tighten the side bearing retainer bolts.
   1. Lock Tite:  THREE BOND 1105 (Part No. 004403010) or equivalent
   2. Tightening torque:  10.3 N.m (1.05 kgf-m, 7.6 ft-lb)
   Fig 28: Tightening Side Bearing Retainer Bolts

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6. Measure the crown gear-to-drive pinion backlash. Set the magnet base on differential carrier. Align the contact point of dial gauge with tooth face of crown gear, and move the crown gear while holding drive pinion still. Read the value indicated on dial gauge.

   If the backlash is not within specification, adjust the side bearing retainer shim as follows.

   1. When backlash is more than 0.2 mm (0.0079 in):  Reduce shim thickness of behind crown gear, and increase shim thickness of crown gear side.
   2. When backlash is less than 0.1 mm (0.0039 in):  Increase shim thickness of behind crown gear, and reduce shim thickness of crown gear side.
   3. Backlash:  0.10 - 0.20 mm (0.0039 - 0.0079 in)
   Fig 29: Measuring Crown Gear-To-Drive Pinion Backlash

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7. If the total preload is not within specification, adjust the thickness of side bearing retainer shims, increasing/reducing by an even amount at a time.
   1. Turning resistance increase:  2.9 - 10.8 N (0.3 - 1.1 kgf, 0.7 - 2.4 lb)

1. Backlash:  0.10 - 0.20 mm (0.0039 - 0.0079 in)

Fig 30: Rechecking Crown Gear-To-Pinion Backlash

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1. Limit of runout:  Less than 0.05 mm (0.0020 in)

Fig 31: Checking Crown Gear Runout On Its Back Surface

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1. Apply an even coat of red lead on both sides of three or four teeth on the crown gear. Check the contact pattern after rotating the crown gear several revolutions back and forth until a definite contact pattern appears on the crown gear.
2. When the contact pattern is incorrect, readjust according to the instructions given in "TOOTH CONTACT PATTERN".

• Correct tooth contact

  Checking item: Tooth contact pattern is slightly shifted toward to toe side under no-load rotation. (When loaded, contact pattern moves toward heel) 

  Fig 32: Identifying Tooth Contact Pattern (Correct Tooth Contact)

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• Face contact

  Checking item: Backlash is too large. 

  Contact pattern

  Fig 33: Identifying Tooth Contact Pattern (Face Contact)

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  Corrective action: Increase thickness of drive pinion height adjusting shim in order to bring drive pinion close to crown gear.

  Fig 34: Increasing Thickness Of Drive Pinion Height Adjusting Shim (Face Contact)

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• Flank contact

  Checking item: Backlash is too small. 

  Contact pattern

  Fig 35: Identifying Tooth Contact Pattern (Flank Contact)

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  Corrective action: Reduce thickness of drive pinion height adjusting shim in order to move drive pinion away from crown gear.

  Fig 36: Reducing Thickness Of Drive Pinion Height Adjusting Shim (Flank Contact)

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• Toe contact (Inside end contact)

  Checking item: Contact area is small. 

  Contact pattern

  Fig 37: Identifying Tooth Contact Pattern - Toe Contact (Inside End Contact)

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  Corrective action: Reduce thickness of drive pinion height adjusting shim in order to move drive pinion away from crown gear.

  Fig 38: Reducing Thickness Of Drive Pinion Height Adjusting Shim (Toe Contact - Inside End Contact)

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• Heel contact (Outside end contact)

  Checking item: Contact area is small. 

  Contact pattern

  Fig 39: Identifying Tooth Contact Pattern - Heel Contact (Outside End Contact)

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  Corrective action: Increase thickness of drive pinion height adjusting shim in order to bring drive pinion close to crown gear.

  Fig 40: Increasing Thickness Of Drive Pinion Height Adjusting Shim (Heel Contact - Outside End Contact)

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1. Drive pinion height

   ST1 398507702 DUMMY SHAFT

   ST2 398507701 DIFFERENTIAL CARRIER GAUGE

   Fig 41: Driving Pinion Height

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   1. T = To + N - (H x 0.01) - 0.20 (mm)
   2. Where:
   3. T = Thickness of pinion height adjusting shim (mm)
   4. To = Thickness of shim temporarily inserted (mm)
   5. N = Reading of thickness gauge (mm)
   6. H = Figure marked on drive pinion head
2. Hypoid gear backlash

1. Backlash:  0.10 - 0.20 mm (0.0039 - 0.0079 in)

Fig 42: Measuring Hypoid Gear Backlash

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1. Lock Tite:  THREE BOND 1105 (Part No. 004403010) or equivalent
2. Tightening torque:  10.3 N.m (1.05 kgf-m, 7.6 ft-lb)

Fig 44: Tightening Side Bearing Retainer Bolts

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