Rear Differential: Assembly

Adjust the bearing preload with spacer and washer between front and rear bearings. Pinion height adjusting washer are not affected by this adjustment. The adjustment must be carried out without oil seal inserted.

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: Inserting Pinion Height Adjusting Washer And Rear Bearing Cone

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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

Tightening torque: 

181 N.m (18.5 kgf-m, 134 ft-lb) 

Fig 5: Tightening Torque Chart

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Fig 6: Identifying Special Tools

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Fig 7: Tightening Torque Chart

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

1. Install the ST2.
   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: Adjusting Drive Pinion Height

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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 Differential Carrier Gauge And End Surface Of Dummy Shaft Using Thickness Gauge

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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.

   T = To + N - (H x 0.01) - 0.20 mm (0.0079 in)

Fig 10: Thickness Of Pinion Height Adjusting Shim Formula Specification

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(Example of calculation)

To = 2.20 + 1.20 = 3.40 mm

N = 0.23 mm

H = + 1

T = 3.40 + 0.23 - 0.01 - 0.20 = 3.42

Result: Thickness = 3.42 mm

Therefore use the shim 383605200.

Fig 11: Shim Specification

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ST 398177700 INSTALLER

Fig 12: Identifying Pinion Height Adjusting Shim

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ST1, ST2 and ST3.

ST1 398507703 DUMMY COLLAR

ST2 399780104 WEIGHT

ST3 899580100 INSTALLER

Fig 14: Pressing Front Bearing Cone

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ST1 399780104 WEIGHT

ST2 899580100 INSTALLER

Fig 15: Pressing Pilot Bearing Using Special Tools

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ST 498447120 INSTALLER

Fig 16: Identifying Oil Seal

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ST1 899874100 INSTALLER

ST2 399780104 WEIGHT

Fig 17: Pressing Companion Flange Using Special Tools

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ST 498427200 FLANGE WRENCH

Tightening torque: 

181 N.m (18.5 kgf-m, 134 ft-lb) 

Fig 18: Tightening Self-Locking Nut Using Special Tool

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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)

1. Measure the side gear backlash.

   Side gear back clearance: 

   0.10-0.20 mm (0.0039-0.0079 in) 

   Fig 20: Measuring Side Gear Backlash

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2. Adjust the backlash as specified by selecting the side gear thrust washer.
   Fig 21: Side Gear Thrust Washer Thickness Specification

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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.

Lock Tite: 

THREE BOND 1324 (Part number: 004403042) or equivalent 

Tightening torque: 

105 N.m (10.7 kgf-m, 77.4 ft-lb) 

Fig 22: Identifying Hypoid Driven Gear

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ST 398237700 DRIFT

Fig 23: Pressing Side Bearing

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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 24: Identifying Differential Case Assembly

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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.
   • Replace the broken or cracked O-ring with new one.
   Fig 25: Side Bearing Retainer Shim Specification

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4. Align the arrow mark on differential carrier with the mark on side retainer during installation.
   Fig 26: Aligning Arrow Mark

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5. Tighten the side bearing retainer bolts.

   Lock Tite: 

   THREE BOND 1105 (Part No. 004403010) or equivalent 

   Tightening torque: 

   10.3 N.m (1.05 kgf-m, 7.6 ft-lb) 

   Fig 27: Tightening Side Bearing Bolts

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6. Measure the hypoid driven gear-to-drive pinion backlash. Set the magnet base on differential carrier. Align the contact point of dial gauge with tooth face of hypoid driven gear, and move the hypoid driven 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.

   When backlash is more than 0.2 mm (0.0079 in): 

   Reduce shim thickness of behind hypoid driven gear, and increase shim thickness of hypoid driven gear side. 

   When backlash is less than 0.1 mm (0.0039 in): 

   Increase shim thickness of behind hypoid driven gear, and reduce shim thickness of hypoid driven gear side. 

   Backlash: 

   0.10-0.20 mm (0.0039-0.0079 in) 

   Fig 28: Measuring 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.

   Turning resistance increase: 

   20.7-54.4 N(2.1-5.5 kgf, 4.7-12.2 lb) 

Backlash: 

0.10-0.20 mm (0.0039-0.0079 in) 

Fig 29: Measuring Backlash

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Limit of runout: 

Less than 0.05 mm (0.0020 in) 

Fig 30: Measuring Backlash

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1. Apply an even coat of red lead on both sides of three or four teeth on the hypoid driven gear. Check the contact pattern after rotating the hypoid driven gear several revolutions back and forth until a definite contact pattern appears on the hypoid driven 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 31: Checking Tooth Contact Of Hypoid Driven Gear

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• Face contact

  Checking item: Backlash is too large. 

  Contact pattern

  Fig 32: Locating Face Contact

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

  Fig 33: Locating Face Contact

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• Flank contact

  Checking item: Backlash is too small. 

  Contact pattern

  Fig 34: Locating Flank Contact

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

  Fig 35: Locating Flank Contact

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• Toe contact (Inside end contact)

  Checking item: Contact area is small. 

  Contact pattern

  Fig 36: Locating Toe Contact From Inside End

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

  Fig 37: Locating Toe Contact From Inside End

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• Heel contact (Outside end contact)

  Checking item: Contact area is small. 

  Contact pattern

  Fig 38: Locating Heel Contact From Outside End

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

  Fig 39: Locating Heel Contact From Outside End

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Lock Tite: 

THREE BOND 1105 (Part No. 004403010) or equivalent 

Tightening torque: 

10.3 N.m (1.05 kgf-m, 7.6 ft-lb) 

Fig 41: Tightening Side Bearing Bolts

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Tightening torque: 

29 N.m (3.0 kgf-m, 21.7 ft-lb) 

Fig 42: Identifying Gasket

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