Assembly
ASSEMBLYNOTE:
^ Assemble in the reverse order of disassembly.
^ Check and adjust each part during assembly.
^ Keep the shims and washers in order, so that they are not improperly installed.
^ Thoroughly clean the surfaces on which the shims, washers and bearings are to be installed.
^ Apply gear oil when installing the bearings.
^ Be careful not to mix up the RH and LH bearing races.
^ Use a new O-ring and gasket.
^ Replace the oil seal with a new part at every disassembly.
^ Be careful not to mix up the oil seal RH and LH.
^ Apply differential gear oil to the lips when installing the oil seal.
1) Adjusting preload for front and rear bearings
NOTE:
Adjust the bearing preload between front and rear bearings with spacer and washer. Pinion height adjusting washer is not affected by this adjustment. The adjustment must not be carried out with oil seal inserted.
2) Using the ST, press-fit the rear bearing race to the differential carrier.
ST 398417700 DRIFT
3) Using the ST, press-fit the front bearing race to the differential carrier.
ST 398477702 DRIFT
4) Selecting the pinion height adjusting washer
1) Measure the thickness of the inserted pinion height adjusting washer.
2) Read the markings on both the current drive pinion gear and the new pinion gear.
NOTE:
No marking means 0 (zero).
3) Calculate the thickness of pinion height adjusting washer to be inserted from the following formula, and replace the installed washer with a new washer of the calculated thickness.
T = T1 + (T2 x 0.01 - T3 x 0.01)
(Example of calculation)
T1 =3.30, T2 = +2, T3 = -1
T = 3.30 + {(2 x 0.01) - (-1 x 0.01)} = 3.33
Calculated result: Thickness = 3.33 mm
The washer with part number 38336AA310 is used.
5) Attach the selected pinion height adjusting washer on drive pinion, and press the rear bearing cone into position with ST.
ST 18674AA000 INSTALLER
6) Insert the drive pinion into the differential carrier, and install the originally attached bearing preload adjusting spacer and washer.
7) Insert the spacer and press-fit the pilot bearing using ST.
ST1 399780104 WEIGHT
ST2 899580100 INSTALLER
ST3 398507703 DUMMY COLLAR
ST4 498937110 HOLDER DRIVE PINION
8) Press-fit the companion flange with ST1, ST2 and ST3.
NOTE:
Be careful not to damage the bearing.
ST1 899874100 INSTALLER
ST2 399780104 WEIGHT
ST3 498937110 HOLDER DRIVE PINION
9) Install the self-locking nut. Tighten it using the ST.
ST 18633AA000 WRENCH COMPL
10) Rotate the drive pinion shaft 10 times or more to fit it in the respective taper roller bearing, and then measure the initial load or initial torque.
11) When the bearing preload is out of the specified range, select the preload adjusting washer and spacer from the following table in order to make it within the specified range.
12) Remove the self-locking nut while holding the companion flange with ST.
ST 18633AA000 WRENCH COMPL
13) Extract the companion flange with a puller.
14) Install a new oil seal using ST.
NOTE:
^ Press-fit until the oil seal end comes 1 mm (0.04 in) inward from end of carrier.
^ Apply differential gear oil to the oil seal lips.
ST 498447120 INSTALLER
15) Press-fit the companion flange with ST1, ST2 and ST3.
ST1 899874100 INSTALLER
ST2 399780104 WEIGHT
ST3 498937110 HOLDER DRIVE PINION
NOTE:
Be careful not to damage the bearing.
16) Install the self-locking nut. Tighten it using the ST.
ST 18633AA000 WRENCH COMPL
17) Check the initial torque or initial load.
18) Install the driven gear to the differential case.
NOTE:
^ Before installing bolts, apply seal material to bolt threads.
^ Tighten opposing bolts in order.
19) Press the side bearing into differential case using ST.
ST 398487700 DRIFT
20) Assembling side retainer
1) Press-fit the side bearing outer race using the ST and press.
ST 398417700 DRIFT
2) Install the oil seal.
21) Side retainer shim adjustment
1) The driven gear backlash and side bearing preload can be adjusted by the side retainer shim thickness.
2) Install the differential case assembly into differential carrier in the reverse order of disassembly.
NOTE:
Be careful that side bearing outer race is not damaged by the bearing roller.
3) Install the side retainer shims and O-ring to the same side retainers RH and LH to which they were originally installed.
NOTE:
^ Replace the O-ring with a new part.
^ Replace broken or corroded side retainer shims with a new part of the same thickness.
4) Align the arrow mark on the differential carrier with the arrow mark on the side retainer during installation.
NOTE:
Be careful that side bearing outer race is not damaged by the bearing roller.
5) Tighten the side retainer bolts.
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 the tooth surface of driven gear, and move the hypoid driven gear while securing the drive pinion. Read the value indicated on dial gauge. If the backlash is outside the standard range, adjust the side retainer shim by the following method.
^ When backlash is less than 0.1 mm (0.004 in):
Reduce the thickness of shim on the back side of the hypoid driven gear and increase the thickness of shims on the teeth side of the hypoid driven gear.
^ When backlash exceeds 0.2 mm (0.008 in):
Increase the shim thickness on the hypoid driven gear rear face and reduce the thickness on the tooth surface side.
7) At the same time, measure the total preload of the drive pinion. If the total preload is not within specification as compared to the resistance when the differential case is not installed, adjust the thickness of the side retainer shims by slightly increasing/reducing both shims by the same amount.
Total preload: 26.5 - 53.0 Nm (2.7 - 5.4 kgf, 6.0- 11.9 lbf)
22) Recheck the hypoid driven gear to drive pinion backlash.
23) Check the hypoid driven gear runout on its back surface, and make sure that the drive pinion and hypoid driven gear rotate smoothly.
If the hypoid driven gear runout on its back surface exceeds the specification, check for any foreign matter between the hypoid driven gear and differential case, and for any deformation of the case or gear.
24) Checking and adjusting the tooth contact of hypoid driven gear
1) Apply lead-free red dye evenly on the both sides of three to four teeth of the hypoid driven gear. Rotate the driven gear several revolutions back and forth until a definite contact pattern appears on the driven gear, and check the contact pattern.
2) When the contact pattern is not correct, readjust.
NOTE:
Be sure to wipe off the lead-free red dye completely after the adjustment is completed.
^ Correct tooth contact
Check item: Tooth contact pattern is slightly shifted toward toe side under no-load rotation. (When driving, it moves towards the heel side.)
^ Face contact
Check item: Backlash is too large.
Contact pattern
Corrective action: Increase thickness of pinion height adjusting washer according to the procedure for bringing drive pinion close to hypoid driven gear side.
^ Flank contact
Check item: Backlash is too small.
Contact pattern
Corrective action: Reduce the thickness of pinion height adjusting washer according to the procedure for bringing drive pinion away from hypoid driven gear.
^ Toe contact (inside contact)
Check item: Teeth contact area is too small.
Contact pattern
Corrective action: Reduce the thickness of pinion height adjusting washer according to the procedure for bringing drive pinion away from hypoid driven gear.
^ Heel contact (outside end contact)
Check item: Teeth contact area is too small.
Contact pattern
Corrective action: Increase thickness of drive pinion height adjusting washer in order to bring the drive pinion closer to the hypoid driven gear.
25) If proper tooth contact is not obtained, readjust the drive pinion height by changing the RH and LH side retainer shims and the hypoid gear backlash.
26) Install the oil seal to the side retainer of both sides.
27) Align the arrow mark on the differential carrier with the arrow mark on the side retainer during installation.
28) Apply liquid gasket to the bolts indicated by arrows, and tighten the side retainer bolt.
29) Install the new gasket and rear cover, and tighten the bolts to the specified torque.
30) Install the air breather cap.
31) Install the oil temperature switch.
NOTE:
^ Use a new gasket.
^ Install the oil temperature switch and adapter as a unit.
Tightening torque: 60 Nm (6.1 kg-m, 44.3 ft-lb)
32) Install the oil drain plug.