Isuzu N-Series. Manual - part 170

REAR AXLE 4B-37

Thickness of shim available, 1.53, 1.56 ... 2.07, 2.10 mm
(0.060, 0.061 ... 0.081, 0.082 in)
11. Flange
12. Flange Nut

(NHR only for collapsible spacer)
1) Tighten the flange nut to a torque of 245 N

⋅m

(25 kg

⋅m/181 lb⋅ft).

2) Make an adjustment by tightening the flange

nut until specified bearing pre-load is obtained.

Bearing preload
New bearing: 16 — 29 N (1.6 — 3.0 kg / 3.5 — 6.6 lb)
Used bearing: 8 — 14.5 N (0.8 — 1.5 kg / 1.8 — 3.3 lb)

Tighten:
Starting to

• New bearing: 0.69 — 1.27 N

⋅m (7.0 — 13.0 kg⋅cm /

6.1 — 11.3 lb

⋅in)

• Used bearing: 0.35 — 0.64 N

⋅m (3.5 — 6.5 kg⋅cm /

3.1 — 5.7 lb

⋅in)

3) The flange nut should be within the specified

range when specified bearing preload is ob-
tained.

Tighten:
Flange nut to 245 — 294 N

⋅m (25 — 30 kg⋅m / 181 —

217 lb

⋅ft)

Discard used flange nut and install new one.
(NKR only for distance piece)
Once specified bearing preload is obtained by
dummy nut, remove dummy nut and replace with
flange nut.
Tighten the flange nut until specified bearing pre-
load and nut torque.
Using special tool, stake the flange nut at two
points.
Punch: 5-8840-2293-0

13. Backlash and Preload Adjusting Shim

1) Adjustment of Backlash

• Install dummy bearing in the differential cage

assembly, then install differential cage assem-
bly and ring gear into the differential carrier.
Install the bearing caps after checking to make
certain setting marks (1) applied at disassem-
bly are in alignment.

Tighten:
Bearing cap bolt to 108 N

⋅m (11.0 kg⋅m /80 lb⋅ft)

N4A0151E

N4A0145E

N4A0151E

4B-38 REAR AXLE

• Set the dial indicator and measure the backlash

between the drive pinion and ring gear at the
foot portion of the ring gear.

Backlash, 0.15 — 0.20 mm (0.006 — 0.008 in)

• To adjust backlash, loosen bearing cap bolts

slightly and move the dummy bearing (1) as
necessary.
A clearance should not be provided between
dummy bearing and bearing fitting face of the
differential cage.

2) Inspection of drive pinion and ring gear tooth

contact.

• Apply a thin coat of red check to faces of the 7

— 8 teeth of the ring gear.

• Check the impression of contact (Right contact)

obtained on the ring gear teeth and make nec-
essary adjustment as described below if the
contact is abnormal.

N4A0152E

N4A0153E

N4A0154E

N4A0155E

REAR AXLE 4B-39

3) Selection of Preload Adjusting Shim

• Measure the clearance (A) between the differ-

ential carrier and right and left side (dummy)
bearings by using a feeler gauge.
Carefully note the relationship between the val-
ues obtained through measurement at each
side and dummy bearings.

• Measure the thickness of dummy bearing and

side bearing.
Comparison should be made between the
thicknesses of dummy bearing and side bear-
ing installed in the same position.

TOOTH CONTACT

CASE

ADJUSTMENT PROCEDURE

Drive pinion is too far 
away from ring gear.

1. Move the drive pinion in to-

ward the ring gear by de-
creasing the thickness of 
pinion depth adjusting 
shims.

2. Adjust the backlash by 

moving ring gear away 
from the drive pinion.

Drive pinion is too close to 
the ring gear.

1. Move the drive pinion away 

from the ring gear by in-
creasing thickness of pin-
ion depth adjusting shims.

2. Adjust the backlash by 

moving ring gear in toward 
the drive pinion.

Ring gear is too close to 
the drive pinion.

1. Move the drive pinion in to-

ward the ring gear by de-
creasing thickness of 
pinion depth adjusting 
shims.

2. Adjust the backlash by 

moving ring gear away 
from the drive pinion.

Ring gear is too for away 
from drive pinion.

1. Move the drive pinion away 

from the ring gear by in-
creasing thickness of pin-
ion depth adjusting shims.

2. Adjust the backlash by 

moving ring gear in toward 
the drive pinion.

N4A0156E

N4A0160E

N4A0157E

N4A0161E

N4A0158E

N4A0162E

N4A0159E

N4A0163E

N4A0164E

4B-40 REAR AXLE

When side bearing is thinner:
A+(dummy bearing thickness

−side bearing

thickness)=(X)
When side bearing is thicker:
A

−(side bearing thickness−dummy bearing

thickness)=(X)

• (X)+0.025=Shim thickness

Allowance for bearing preload at one
side=0.025

Thickness of shim available, 0.25, 0.30, 0.35, 0.5 mm
(0.009, 0.012, 0.014, 0.019 in)

14. Side Bearing Inner Race

Installer: 5-8840-2050-0
Grip: 9-8522-1608-0

15. Differential Cage Assembly
16. Side Bearing Outer Race
17. Bearing Cap

1) Install bearing caps by aligning setting marks

(1) applied at disassembly.

Tighten:
Bearing cap bolt to 108 N

⋅m (11.0 kg⋅m /80 lb⋅ft)

Legend

1. Dial gauge
2. Dummy bearing
3. Side bearing

Example of calculation

mm (in.)

Measured Clearance A:

+0.85 (+0.033)

Suppose that the side bearing is 
thicker [thinner] than dummy 
bearing by 0.05 mm

−0.05 (−0.002) 

[+0.05 (+0.002)]

An allowance for bearing pre-
load:

+0.025 (+0.0009)

Thickness of shims to be 
installed:

0.825 (0.032) 

[0.925 (0.036)]

N4A0165E

Legend

A. Measured clearance

A

′. Shim installed position

N4A0166E

N4A0167E