2001 INFINITI QX4 differential

SPD359A
INSPECTIONNBPD0037Contact SurfacesNBPD0037S011. Clean the disassembled parts in suitable solvent and blow dry
with compressed air.
2. If following surfaces are found with burrs or scratches, smooth
with oil stone.
1Differential case B
2Differential case A
3Side gear
4Pinion mate gear
5Pinion mate shaft
6Friction plate guide
Disc and PlateNBPD0037S021. Clean the discs and plates in suitable solvent and blow dry with
compressed air.
2. Inspect discs and plates for wear, nicks and burrs.
SPD279
3. To test if friction disc or plate is not distorted, place it on a sur-
face plate and rotate it by hand with indicating finger of dial
gauge resting against disc or plate surface.
Allowable warpage:
0.08 mm (0.0031 in)
If it exceeds limits, replace with a new plate to eliminate pos-
sibility of clutch slippage or sticking.
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REAR FINAL DRIVEH233B
Limited Slip Differential (Cont'd)
PD-49

SPD381A
4. Measure frictional surfaces and projected portions of friction
disc, friction plate, spring plate, and determine each part's dif-
ferences to see if the specified wear limit has been exceeded.
If any part has worn beyond the wear limit, and deformed or
fatigued, replace it with a new one that is the same thickness as
the projected portion.
Wear limit:
0.1 mm (0.004 in) or less
AþB=Wearlimit mm (in)
I: Measuring points
A: Projected portion
B: Frictional surface
SPD383A
SPD417
ADJUSTMENTNBPD0038Friction Disc and Friction Plate End PlayNBPD0038S01End play of friction disc and friction plate can be calculated by using
following equation and should be adjusted within following range.
Adjustment can be made by selecting friction disc having two dif-
ferent thicknesses.
End play E:
0.05 - 0.15 mm (0.0020 - 0.0059 in)
E=Aþ(B+C)
A: Length of differential case contact surface to differential case
inner bottom.
B: Total thickness of friction discs, friction plates, spring disc and
spring plate in differential case on one side.
C: Length of differential case contact surface to back side of side
gear.
1. Measure values of ªAº.
Standard length A:
49.50 - 49.55 mm (1.9488 - 1.9508 in)
SPD420
2. Measure thickness of each disc and plate.
Total thickness ªBº:
19.24 - 20.26 mm (0.7575 - 0.7976 in)
REAR FINAL DRIVEH233B
Limited Slip Differential (Cont'd)
PD-50

SPD418
3. Measure values of ªCº.
a. Attach a dial indicator to the base plate.
b. Place differential case B on the base plate, and install a mas-
ter gauge on case B.
Then adjust the dial indicator scale to zero with its tip on
the master gauge.
SPD419
c. Install pinion mate gears, side gears and pinion mate shaft in
differential case B.
d. Set dial indicator's tip on the side gear, and read the indication.
Example:
E = A þ D = A þ (B + C) = 0.05 to 0.15 mm
A = 49.52 mm
B = 19.45 mm
C = 29.7 mm
D=B+C
49.15 (D) = 19.45 (B) + 29.7 (C)
E =Aþ D
0.37 (E) = 49.52 (A) þ 49.15 (D)
From the above equation, end play of 0.37 mm exceeds the speci-
fied range of 0.05 to 0.15 mm.
Select suitable discs and plates to adjust correctly.
SPD421
ASSEMBLYNBPD0039Prior to assembling discs and plates, properly lubricate them by
dipping them in limited slip differential oil.
1. Alternately position specified number of friction plates and fric-
tion discs on rear of side gear.
Always position a friction plate first on rear of side gear.
SPD384A
2. Install spring plate.
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REAR FINAL DRIVEH233B
Limited Slip Differential (Cont'd)
PD-51

SPD385A
3. Install friction plate guides.
Correctly align the raised portions of friction plates, and apply
grease to inner surfaces of friction plate guides to prevent
them from falling.
SPD386A
4. Install differential case B over side gear, discs, plates and fric-
tion plate guide assembly.
IInstall differential case B while supporting friction plate
guides with your middle finger inserted through oil hole in
differential case.
IBe careful not to detach spring disc from the hexagonal
part of the side gear.
SPD426
5. Install pinion mate gears and pinion mate thrust washers on
pinion mate shaft, then install pinion mate shaft in differential
case B.
SPD387A
6. Install side gear to pinion mate gears.
7. Install each disc and plate.
Use same procedures as outlined in steps 1. through 4. above.
SPD388A
8. Install differential case A.
Position differential cases A and B by correctly aligning marks
stamped on cases.
REAR FINAL DRIVEH233B
Limited Slip Differential (Cont'd)
PD-52

SPD364A
9. Tighten differential case couple bolts.
10. Place ring gear on differential case and tighten ring gear bolts.
Tighten bolts in a criss-cross pattern, lightly tapping bolt head
with a hammer.
Then bend up lock straps to lock the bolts in place.
11. Install side bearing inner cone.
12. Check differential torque.
AdjustmentNBPD0040For quiet and reliable final drive operation, the following five adjust-
ments must be made correctly:
1. Side bearing preload
2. Pinion gear height
3. Side bearing preload
4. Ring gear-to-pinion backlash. Refer to SDS, PD-62.
5. Ring and pinion gear tooth contact pattern
SPD196A
PINION GEAR HEIGHTNBPD0040S011. Make sure all parts are clean and that the bearings are well
lubricated.
2. Assemble the pinion gear bearings into the pinion pre-load
shim selector tool, J34309.
SPD197A
IRear Pinion BearingÐ the rear pinion bearing pilot,
J34309-8, is used to center the rear pinion bearing only. The
rear pinion bearing locking seat, J34309-4, is used to lock the
bearing to the assembly.
IFront Pinion BearingÐ make sure the J34309-3, front pin-
ion bearing seat is secured tightly against the J34309-2 gauge
anvil. Then turn the front pinion bearing pilot, J34309-5, to
secure the bearing in its proper position.
SPD216A
3. Place the pinion preload shim selector tool gauge screw
assembly, J34309-1, with the pinion rear bearing inner cone
installed, into the final drive housing.
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REAR FINAL DRIVEH233B
Limited Slip Differential (Cont'd)
PD-53

SPD007-B
SPD552
AssemblyNBPD0041DIFFERENTIAL CASENBPD0041S011. Install side gears, pinion mate gears and thrust washers into
differential case.
SPD258
2. Fit pinion mate shaft to differential case so that it meets lock
pin holes.
3. Adjust backlash between side gear and pinion mate gear by
selecting side gear thrust washer.
Refer to SDS, PD-62.
Backlash between side gear and pinion mate gear
(Clearance between side gear thrust washer and differ-
ential case):
0.10 - 0.20 mm (0.0039 - 0.0079 in)
SPD030
4. Install pinion mate shaft lock pin with a punch.
Make sure lock pin is flush with case.
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REAR FINAL DRIVEH233B
Adjustment (Cont'd)
PD-57

SPD322
5. Apply gear oil to gear tooth surfaces and thrust surfaces and
check to see they turn properly.
6. Install differential case assembly on ring gear.
Tighten bolts in a criss-cross pattern, lightly tapping bolt head
with a hammer.
PD244
7. Press-fit side bearing inner cones on differential case with Tool.
Tool number:
A ST33190000 (J25523)
B ST33081000 ( Ð )
SPD580
DIFFERENTIAL CARRIERNBPD0041S021. Press-fit front and rear bearing outer races with Tools.
Tool number:
A ST30611000 (J25742-1)
B ST30621000 (J25742-5)
C ST30613000 (J25742-3)
SPD377
2. Select drive pinion height adjusting washer. Refer to
ªAdjustmentº, PD-53.
3. Install drive pinion adjusting washer in drive pinion, and press-
fit pinion rear bearing inner cone in it, with press and Tool.
Tool number:
ST30901000 (J26010-01)
REAR FINAL DRIVEH233B
Assembly (Cont'd)
PD-58

SPD149
SPD684
9. Turn drive pinion in both directions several times, and measure
pinion bearing preload.
Tool number: ST3127S000 (J25765-A)
Pinion bearing preload (Without front oil seal):
1.2 - 2.0 N´m (12 - 20 kg-cm, 10 - 17 in-lb)
If preload is out of specification, adjust the thickness of spacer and
shim combination by replacing shim and spacer with thinner one.
IStart from the combination of thickest spacer and shim.
ICombine each spacer and shim thickness one by one until the
correct specification are achieved.
Drive pinion bearing preload adjusting spacer and
shim:
Refer to SDS, PD-64.
10. Install differential case assembly with side bearing outer races
into gear carrier.
11. Position side bearing adjusters on gear carrier with threads
properly engaged; screw in adjusters lightly at this stage of
assembly.
Tool number: ST32580000 (J34312)
SPD265
12. Align mark on bearing cap with that on gear carrier and install
bearing cap on gear carrier.
IDo not tighten at this point to allow further tightening of side
bearing adjusters.
SPD246
13. Tighten both right and left side bearing adjusters alternately
and measure ring gear backlash and total preload at the same
time. Adjust right and left side bearing adjusters by tightening
them alternately so that proper ring gear backlash and total
preload can be obtained.
Ring gear-to-drive pinion backlash:
0.13 - 0.18 mm (0.0051 - 0.0071 in)
SPD149
IWhen checking preload, turn drive pinion in both direc-
tions several times to set bearing rollers.
Tool number: ST3127S000 (J25765-A)
Total preload:
P
1+ [0.3 - 0.4 N´m (3 - 4 kg-cm, 2.6 - 3.5 in-lb)]
P
1: Drive pinion preload
REAR FINAL DRIVEH233B
Assembly (Cont'd)
PD-60