differential JEEP CJ 1953 User Guide

'Jeep'
UNIVERSAL
SERIES
SERVICE
MANUAL

M
M-19.
SERVICE
DIAGNOSIS

SYMPTOMS
PROBABLE
REMEDY

Hard Steering
Lack
of
Lubrication
Lubricate
Tires
Soft.
. Inflate

Tight
Steering. Adjust. See "Steering" Section

Low Speed Shimmy
or
Wheel Fight
Spring
Clips and Shackles Loose
Front
Axle Shifted Insufficient Toe-In

Improper
Caster
Steering System Loose or Worn
Twisted Axle

High Speed Shimmy
or
Wheel Fight
Check
Conditions Under "Low Speed Shimmy"

Tire
Pressures Low or not
Equal

Wheel Out of Balance
Wheel Runout
Radial
Runout of Tires
Wheel Camber
Front
Springs
Settled
or Broken
Bent Steering Knuckle
Arm..................

Shock Absorbers not Effective
Steering
Gear
Loose on Frame

Front
Springs too Flexible

Tramp
Wheels Unbalanced

Wandering
Improper
Toe-in

Broken
Front Spring Main
Leaf

Axle Shifted Loose Spring Shackles or Clips
Improper
Caster

Tire
Pressure Uneven
Tightness in Steering System
Loose Wheel Bearings
Front
Spring
Settled
or Broken
Axle
Noisy
on
Pull
Pinion and Ring
Gear
Adjusted too Tight
Pinion Bearings Rough.

Axle Noisy
on
Coast
Excessive Back
Lash
at Ring and Pinion Gears.

End
Play in Pinion Shaft. . . Rough Bearing.

Axle Noisy
on
Coast
and
Pull
Ring
and Pinion Adjusted too Tight
Pinion Set too
Deep
in Ring
Gear
Pinion Bearing Loose or Worn

Back Lash
Axle Shaft Universal Joint Worn
Axle Shaft Improperly Adjusted

Worn
Differential Pinion Washers
Worn
Propeller Shaft Universal Joints.
Readjust
or Replace

Broken
Spring Center Bolt

Adjust
Reset

Adjust
or Overhaul Steering
Gear,
Front Axle or
Steering Parts
Straighten or Adjust
Inflate
Balance
Straighten Mount Properly
Same on Both Wheels
Repair
or Replace
Straighten or Replace
Replace or Repair Tighten

Over
Lubricated

Check
and Balance

Adjust—Check
for Bent Steering Knuckle Arm Replace

Spring
Center Bolt Broken
Adjust
or Replace
Reset Inflate

Adjust
Adjust
Repair
or Replace

Readjust

Replace

Readjust
Readjust

Replace

Readjust Readjust
Readjust
or Replace
Replace
Readjust

Replace

Repair

Emergency
Where difficulty is experienced with front axle differential making the vehicle inoperative,

remove
axle driving
flanges.
This will allow bringing vehicle in under its own power. Be sure the transfer
case
shift lever is in the neutral
(disengaged)
position.
285

FRONT
AXLE

M-20.
FRONT
AXLE
SPECIFICATIONS

MODEL:
Four
Wheel Drive
Models
Two Wheel Drive
Models

Front
Axle:
Make.

Model
Capacity

Description

Universal
Joints: Make

Type.
King
Pin Bearing Preload
Differential:
Drive
Pinion Offset:
Number of Differential Pinions

Gear
Ratio:
F4
Engine
Standard
Optional

V-6
Engine
Standard
Optional

Ring
Gear Pitch Diameter
Pinion Adjustment
Pinion Bearing Adjustment
Dana

27AF

2000
lb. [907 kg.] Full-floating
Hypoid Gears
Spicer

Cardan
Cross
12 to 16 lb. [5,44 a 7,25 kg.]
1.38*
[35,05
mm.] 2

4.27:1
5.38:1

3.73:1
4.88:1

7.12'
[19,05
cm.]

Shim Shim
Clark

130097

2000
lb. [907 kg.] Reverse Elliot 286

'Jeep*
UNIVERSAL SERIES SERVICE
MANUAL

N
REAR
AXLE

Contents
PAR. SUBJECT
PAR.

N-l POWR-LOK DIFFERENTIAL
N-20
Chatter
.N-26 Dissasembly and Reassembly. .N-23
Torque Test .N-22
21* Trouble Symptoms N-21
SUBJECT

GENERAL
REAR
AXLE SHAFT
AND
BEARING REMOVAL
Semi-Float-Tapered Axle Shaft
Semi-Float-Flanged Axle Shaft
Semi-Float-Flanged Axle Shaft
Bearing Installation. N-8

UNIT
BEARING ASSEMBLY
N-4 Servicing Unit Bearing. N-5

Lubricating
Unit Bearing............... N-6
Unit
Bearing Removal
.
N-7

REAR
AXLE ASSEMBLY
N-9 Cleaning and Inspection.
..............N-15

Differential Bearing Preload and Ring
Gear
Backlash Adjustment.
..........
.N-l9
Differential Case Disassembly N-l2
Differential Case Reassembly N-l7
Differential Side
Gear
Adjustment. . .... .N-18
Inspection and Servicing N-10 Pinion Bearing Cup Removal .N-l4
Pinion Installation and Adjustments. ... .N-l6 Pinion and Differential Bearing Removal N-13

Rear
Axle Assembly Removal N-ll

N-l. GENERAL
A
semifloating
rear axle assembly is standard on
all
Jeep Universal Series vehicles. Two
models
of

similar
design
rear
axles
are used. See Specifi­

cations
Chart,
Par. N-38, for description and ratio.

The
axle
model
number is cast
into
the
housing
as
FIG.
N-l—AXLE MODEL IDENTIFICATION

illustrated in Fig. N-l. A metal tag under two ad­
jacent differential
housing
cover cap screws is
stamped to
identify
the number of
teeth
in the
drive
gear
and pinion and
notes
the axle ratio. A
REAR
AXLE ASSEMBLY
INSTALLATION
N-33

TRAC-LOK
DIFFERENTIAL.
..........
.N-24
Lubrication
N-25 Trouble Symptoms N-26

Unit
Inoperative N-2 7 Disassembly N-28, N-29 Inspection .N-30
Reassembly .N-31

Trac-Lok
Unit Replacement .N-32

Backlash
N-35

TROUBLE
SHOOTING
DIFFERENTIAL
N-34

Rear
Wheel
Noise
.N-36

SERVICE
DIAGNOSIS
.N-37

REAR
AXLE SPECIFICATIONS.
. N-38

Powr-Lok
or
Trac-Lok
differential can be identi­
fied by a separate metal tag attached to the
hous­

ing cover, as shown in Fig. N-2. Information for wheel bearing adjustment is
given
in Section Q.
FIG.
N-2—RATIO,
POWR-LOK
AND

TRAC-LOK
DIFFERENTIAL IDENTIFICATION
1—Ratio Tag 2—Powr-Lok or
Trac-Lok
Tag
N-2.
REAR AXLE SHAFT REMOVAL
AND
INSTALLATION
(Semi-Float Tapered Shaft)
Procedure for removing the rear axle
shafts
is as

follows:
a.
Jack
up the wheel and
remove
the hub cap.
b. Remove wheel. 287

FIG.
N-3—SEMIFLOATING REAR
AXLE
—
TAPERED SHAFT

1— Differential Bearing Cup
2— Differential Bearing Cone and Rollers
3— Shims
4— Differential Case 5—
Ring
Gear and Pinion
6— Pinion Inner Bearing Cone and Rollers
7— Pinion Inner Bearing Cup
8— Pinion Shims
9— Axle
Housing

10— Pinion Outer Bearing Cup
11— Pinion Outer Bearing Cone and Rollers 12—
Oil
Slinger
13— Gasket
14— Pinion Oil Seal
15— Dust Shield
16— Yoke
17—
Flat
Washer
18— Pinion Nut 19— Wheel Bearing Shims
20— Bearing Cup
21— Bearing Cone and Rollers
22—
Oil
Seal 23—
Thrust
Washer
24— Differential Pinion Gears
25—
Thrust
Washer
26— Axle Shaft 27—
Thrust
Block
28— Gasket 29—
—Housing
Cover
30— —Screw and Lock Washer
31—
Filler
Plug 32— Differential Shaft
33—
Lock
Pin
34—
Ring
Gear Screw

c.
Remove the axle shaft cotter pin, castle nut,

and
flat washer.

d.
Back
off on brake adjustment eccentric.
FIG.
N-4—WHEEL
HUB
PULLER
e. Use Wheel Hub Puller C-319 to remove the
wheel hub as shown in Fig. N-4.
f. Remove the screws attaching the brake dust
protector, grease and bearing retainers, brake as­
sembly, and shim to the housing.
g. Remove the hydraulic line from the brake as­ sembly.

h.
Remove the dust shield and oil seal.

i.
Using Tool C-637 and Adapter Tool SP-342,
remove the axle shaft bearing cone, roller, and cup
as shown in Fig. N-5.

j.
Should an axle shaft be broken, the inner end

can
usually be drawn out of the housing with a

wire
loop
after the outer oil seal is removed. How­ ever, if the broken end is
less
than 8" [20,3 cm.]
long it
will
usually be necessary to remove the

differential
assembly.

To
remove the bearing from an axle shaft, use

Combination
Bearing Puller W-104-B shown in
Fig.
N-6.
Installation
is the reverse of removal.

Note:
Place the hub and drum on the axle shaft
taper and then insert the axle shaft key in the
keyway.
Never install the key in the keyway before

placing
the hub and drum assembly on the axle
shaft
Further,
be sure that the axle shaft nut is torqued to a minimum of 150 lb-ft. [21 kg-m.j. 288

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

N

11465
FIG.
N-S—REMOVING
TAPERED
AXLE
SHAFT
1—Cone and Roller 2—Axle 3—Tool C-637

Check
the shaft oil seal
before
installing the rear
axle. If replacement is necessary, use Axle Shaft
Oil
Seal Driver W-186, Fig. N-l7.
Before installing the axle shaft nut
cotter
pin, ad­
just the wheel bearings as outlined in Section Q.
FIG.
N-6—REMOVING
AXLE
SHAFT BEARING —
TAPERED SHAFT
N-3.
Rear
Axle Shaft Removal (Sercii-Float-Flanged Shaft)
a.
Jack
up vehicle and
remove
wheels.
b. Remove brake drum.
c. Remove axle shaft
flange
cup plug by piercing
the center with a sharp
tool
and prying it out.
d. Using
access
hole
in axle shaft
flange
remove
@ ® (30) (29)

FIG.
N-7—SEMI-FLOAT REAR
AXLE
ASSEMBLY — FLANGED SHAFT
1— Differential Bearing Cup
2— Differential Bearing
3— Shims
4— Differential 5—
Ring
Gear
and Pinion 6— -Pinion Inner Bearing
7— Pinion Inner Bearing Cup
8— Pinion Shims
9— Axle Housing
10— Breather
11— Pinion Outer Bearing Cup
12— Pinion Outer Bearing 13—
Oil
Slinger
14— Pinion Oil Seal
15— Dust Shield
16—
Yoke

17—
Flat
Washer
18— Pinion Nut
19— Axle Housing Oil Seal
20— Axle Shaft Retainer Ring
21— Axle Shaft Bearing
22— Axle Shaft Oil Seal
23— Axle Shaft Retainer Plate
24— Axle Shaft Cup Plug 25— Axle Shaft
26—
Thrust
Washer
27— Differential Pinion Gears
28—
Thrust
Washer 29— Gasket
30— Housing Cover 31— Screw and Lockwasher
32—
Filler
Plug 33—
Lock
Pin 34— Differential Shaft
35—
Ring
Gear
Screw 289

'Jeep*
UNIVERSAL
SERIES
SERVICE
MANUAL

N

FIG.
N-l6—AXLE
SHAFT
BEARING
INSTALLED
1—
Retainer
Ring

2—
Unit
Bearing

3—
Seal

4—
Retainer
Plate
5—
Axle
Shaft
Flange
N-9.
REAR
AXLE
ASSEMBLY

The
following
paragraphs
(Pars.
N-9 through N-19)
describe the removal, disassembly, assembly and
services performed on
rear
axle assemblies having
conventional differentials.
Pars.
N-20 through N-32 describe the services to be performed on
rear
axle
assemblies having
Powr-Lok
and
Trac-Lok
dif­
ferentials.

Note:
The
full
floating front axle differential as­
sembly is similar to the
rear
axle differential and is
removed, inspected, disassembled, and assembled
in
the same manner as the
rear
axle differential
covered in this section.
FIG.
N-l
7—OIL
SEAL
DRIVER

Note:
The pinion shaft oil seal is serviced in the
vehicle when replacement is necessary. Refer to

Fig.
N-l8.
11851
j

J

FIG.
N-l8—REMOVING
PINION
SHAFT
OIL
SEAL

1—Tool
W-251 N-10. Inspection

Refer
to Fig. N-3 and N-7. Before disassembling the differential, it is advisable
to determine through inspection the cause of the

failure.
Inspection procedure is as follows:

a.
Drain
lubricant and remove housing cover and gasket.

b.
Clean
the differential parts thoroughly with sol­
vent.

c.
Carefully
inspect all parts.

Should
it be determined by inspection that the

differential
requires overhauling, the axle must first
be removed from the vehicle.

Note:
All service replacement axle assemblies are
shipped from the factory without lubricant in the

differential.
Lubricant
must be added to the dif­

ferential
before
the axles are installed in vehicles.

Use
the grade and quantity of lubricant specified
in
the
Lubrication
Chart.

After
the axle has
been
installed in the vehicle,
check
to be sure the lubricant level in the differen­

tial
is up to the filler plug opening.

N-l
1.
Rear
Axle Removal

To
remove the
rear
axle, proceed as follows:
a.
Raise the
rear
of the vehicle with a hoist. Safely
support the frame ahead of the
rear
springs.

b.
Remove the wheels.

c.
Disconnect the propeller shaft at the
rear
yoke.

d.
Disconnect the shock absorbers at the axle
mounting.
e. Disconnect the brake hydraulic
hose
at the tee
fitting on the axle just
below
the
left
frame side
rail.
Tape
ends
of
hose
to
keep
out
dirt.

f. Disconnect the parking brake cable at the frame
mounting. DJ
models
only.
g. Support the axle housing on a
jack.

h.
Remove the axle U-bolts.
i.
Slide the axle from under the vehicle. 293

N

REAR AXLE
N-l2.
Differential Case
Disassembly

Refer
to
Fig.
N-3 and N-7.

a.
Remove
the
axle shafts. Refer
to
Par.
N-ll for

rear
axle removal
and
Par.
M-4 for
front axle
re­

moval.

b.
Remove
the
housing cover
and
four
cap
screws
holding
the two
differential side bearing caps
in

position. Make sure there
are
matching letters
or
some
type
of
identification marks
on the
caps
and

housing
so
that each
cap can be
reinstalled
in the

same position
and
location from which
it is re­

moved.

c.
Use
Spreader W-129,
as
shown
in
Fig. N-l9,
to

spread
the
housing.
Install
Hold-Down Clamps
W-129-18.
if
available,
to
keep
the
spreader
in
position.
Clamp
on a
dial
indicator.
From
the
side,
measure
the
carrier
spread.
Do not
spread
the
car­
rier
more than
.020"
[0,508
mm.].

d.
Remove
the
dial
indicator.
FIG.
N-19—DIFFERENTIAL
CARRIER
SPREADER

TOOL
W-129

1—
Spreader
W-129

2—
Dial
Indicator
and
Pointer

3—
Dial
Indicator
Clamp
Note:
When removing
the
axle differential from
the
rear
axle housing,
use
Spreader Tool
No.

W-129.

e.
Carefully
pry the
differential case
loose,
using

pry
bars
at the
heads
of the
ring gear
bolts
and

carrier
casting.

f.
Remove spreader immediately
to
prevent
the
possibility
of the
carrier
taking
a set.

g. Remove
the
screws holding
the
ring gear
to the

differential
case.

h.
With
a
small punch,
as
shown in
Fig.
N-20, drive
out
the
lock
pin.
FIG.
N-20—REMOVING
LOCK
PIN

i.
Remove
the
differential shaft
and
thrust block.

Note:
Thrust
block used with semi-float tapered
axle shaft only. Refer
to
Fig.
N-3.

j.
Carefully
so as not to
lose
the
thrust washers,
remove
the
differential pinion gears.

k.
With
Tool C-3281
to
hold
the
shaft
as
shown

in
Fig.
N-21,
remove
the nut.
With
Puller
W-172

remove
the
yoke
as
shown
in
Fig. N-2
2.

I.
Using
a
rawhide hammer, drive
on the end of

the pinion shaft
to
force
the
pinion
out of the

differential
housing.
FIG.
N-21—END
YOKE
HOLDING WRENCH

1— Nut

2—
Wrench
C-3281

3—
Yoke
Note:
Pinion bearing adjusting shims
may
remain
on
the
pinion shaft; stick
to the
bearing which
is
still
in the
housing;
or
fall
out
loose.
These shims
should
be
collected
and
kept
for
reassembly.

m.
Remove outer pinion bearing
cone,
baffle
and

oil
seal
by
using
a 2" x 2"
piece
of
hardwood
or a
length
of
pipe
and
drive
out
through
the
neck
of

the
carrier
housing.
Discard
seal. 294

'Jeep*
UNIVERSAL
SERIES SERVICE
MANUAL

N

FIG.
N-2
2—END
YOKE PULLER

FIG.
N-23—REMOVING
CONE
AND
ROLLER
WITH
PULLER
N-13. Pinion
and
Differential
Case

Bearing
Removal

To
remove the differential bearing
cones
and rollers

and
pinion inner bearing
cone
and roller,
use
Bear­
ing Puller W-104-B with proper adapters
as
shown

in
Fig. N-23 and N-24. Use of the
puller
and

adapters assures easy removal
of
bearings without
damage
to
cone
rollers as pulling pressure
is
applied
directly
to the
bearing
cone.
The information
out­

lined
below
references
the
axle model and adpater
plate number used with Puller W-104-B when
re­

moving tapered roller bearings from
the
axle
as­
sembly components.

Axle Model Axle Shaft Bearing Pinion Bearing Differential (Tapered Shaft) Side Carrier Bearing
27
#
41
Adapter
#
40 Adapter
#
39
Adapter with
SP-1100

44
#13
Adapter
#21
Adapter
#
18
Adapter with SP-1100
FIG.
N-24—PULLING PINION
INNER
BEARING

1— Puller Tool W-104-B
2—
-Adapters
N-14. Pinion Bearing
Cup
Removal

Note:
The differential
carrier
housing
has recesses

in
the
casting
to
permit
the use of a
brass drift
to

drive
the
inner
and
outer bearing cups from
the

housing.

a.
Using
a
brass drift, drive
the
pinion inner bear­
ing
cup and
shims from
the
housing.
Even
if

mutilated,
these
shims should
be
kept
for
proper
assembly
of
differential.
b. Using
a
brass drift, drive
the
outer pinion
cup

from
the
housing.
N-15. Cleaning
and
Inspection

a. Clean
all
parts
in
fast evaporating mineral
spirits or
a
dry cleaning solvent and with
the
excep­
tion
of
bearings,
dry
with compressed air.
b. Inspect differential bearing
cones,
cups
and

rollers
for
pitting, galling
or
other visible damage.
c. Inspect differential case
for
elongated
or en­
larged pinion shaft hole.
The
machined thrust
washer surface areas
and
counterbores must
be
smooth
and
without metal
deposits
or
surface
im­

perfections.
If any of the
above
conditions exist,
satisfactory correction must
be
made
or the
case replaced. Inspect case
for
cracks
or
other visible
damage which might render
it
unfit
for
further
service.

d.
Inspect differential pinion shaft
for
excessive

wear
in
contact area
of
differential pinions. Shaft should
be
smooth
and
round with
no
scoring
or
metal pickup

e.
Inspect differential side gears and pinions;
they

should have
smooth
teeth
with
a
uniform contact
pattern without
excessive
wear
or
broken surfaces.
The
differential side gear and pinion thrust washers
should
be
smooth
and
free from
any
scoring
or
metal pickup.
295

N

REAR
AXLE
f. Inspect axle shaft thrust block for
excessive

wear
or visible damage. The wear surface on the op­
posite
ends
of the blocks, must be smooth.

Note:
Thrust
block used with semi-float tapered
axles only.
g. Inspect differential pinion shaft lock pin for
damage or
looseness
in case. Replace pin or case as necessary.

h.
Inspect drive gear and pinion for worn or
chipped
teeth
or damaged attaching
bolt
threads.
If
replacement is necessary, replace both the drive
gear and drive pinion as
they
are available in
matched
sets
only.

i.
Inspect drive pinion bearing
cones,
cups and

rollers
for pitting, galling,
excessive
wear, or other
visible damage. If inspection reveals that either are
unfit for further service, replace both cup and
cone,

j.
Inspect differential
carrier
for cracks or other
visible damage which would render it unfit for
further
service. Raised metal on the shoulder of
bearing cup bores
incurred
in removing pinion cups should be flattened by use of a flat
nose
punch.

k.
Inspect drive pinion for damaged bearings

journals
and mounting shim surface or excessively

worn
splines. If replacement is necessary, replace both the drive pinion and drive gear as
they
are
available in matched
sets
only.
I.
Inspect companion
flange
for
cracks,
worn
splines, pitted, rough or corroded oil seal contacting

surface.
Repair
or replace companion
flange
as
necessary.

m.
Inspect drive pinion bearing shim pack for

broken,
damaged or distorted shims. Replace if
necessary during establishment of pinion bearing

preload.

N-16.
Pinion
Installation
and Adjustment

Refer
to
Fig.
N-3 and N-7.

Adjustment
of the pinion is accomplished by the use of shims placed
between
the inner bearing cup

and
the axle housing and
between
the pinion shoulder and the outer bearing. The shims behind
FIG.
N-2
5—INSTALLING
OUTER BEARING
CUP
FIG.
N-26—PINION
BEARING INSTALLING
SLEEVE

1—Sleeve
the inner bearing cup adjust the position of pinion

in
relation to the ring gear. The shims behind the outer bearing adjust the pinion inner and outer
bearing preload.
Install
the pinion as follows:

a.
Install
outer bearing cup using Tool W-264 on model 27 and W-126 on model 44 axles, as shown

in
Fig. N-25.
b.
Install
the inner bearing cup using Tool W-126
on model 27 axles, and Tool W-344 on model 44
axles to drive the cup
into
the housing.
c. Use Tool C-3095 to press the inner bearing
cone

and
roller
onto
the pinion shaft on axle Model 44.

Other
models
use Tool W-262 as shown in Fig.
N-26.

d.
Place the pinion in the housing and install a .065"
[1,651
mm.] shim, the inner
cone
and roller*

sleeve
SP-1997 from Tool W-162, and the pinion
nut.
e. Select the proper pinion adjusting
gauge
to obtain the correct reading for the differential model.

The
pinion adjusting fixture must first be set by the use of a master
gauge
which is included in the
W-99
Kit. Gauge block W-101-A-24 or SP5433 is stamped with the letter H which indicates it is used
to set the adjusting fixture on Model
27AF
axle differentials. Gauge block W-101-A-22 or SP5453 is stamped with the letters D, G, F, A, C, E and B.
Use the letter E for Model 44 axle differentials.
Tool
SP-5264 is used with the
dial
indicator in

W-99
Tool Set for
setting
pinion.
After
selecting the proper
gauge,
the adjusting fix­
ture can be set as follows: 296

'Jeep'
UNIVERSAL
SERIES SERVICE
MANUAL

N
f. Place the
gauge
block against the machined
sur­

face of the dial indicator mount, as shown in Fig.
N-2 8.
g. Set the dial indicator on zero by rotating the face.

h.
Install
the pinion adjusting fixture on the pinion

with
the stationary
guide
pin and the adjustable
guide
pin
seated
in pinion shaft lathe centers, as
shown in Fig. N-2 7.
FIG.
N-2
7—PINION
ADJUSTING FIXTURE
7—
C-Clamp

8— Sleeve Bearing
9—
Inner
Bearing
10— Housing 11—
Stationary
Guide Pin
1—
Dial
Gauge Swing Arc
2—
Pinion

3—
Flange

4—
Yoke

5—
Thumb
Screw
6—
Guide
Pin 12—Pinion Housing

Note:
Use the "C"
type
alignment fixture ver­

tically
as shown in Fig. N-29, so that
weight
of jig assembly is always directly centered and supported
on pinion shaft center. The function of the fixture is to accurately hold the dial indicator and its
FIG.
N-28—SETTING
PINION
GAUGE FOR
MODEL
27AF
AXLE
DIFFERENTIAL
1—
Dial
Indicator
2—
Gauge
Block
3—
Stationary
Pin
4—
C-Clamp
j
11534 j

FIG.
N-29—CHECKING
PINION
ADJUSTMENT mount in alignment to the pinion shaft while it is
pivoted on the stationary
guide
pin. If a consistent
repeat dial reading cannot be obtained, look for
dirty
or burred pinion centers or a
bent
or twisted
aligning jig. Keep jig flat in metal case when not
in
use. Do not allow other
tools
to rest on it
Treat

the C-type fixture
tool
carefully as a precision in­
strument.

i.
Seat the
gauge
mount firmly on the pinion head

and
swing the dial indicator through the differential
bearing bore as shown in
Fig.
N-29.

j.
The
lowest
reading indicates the center of the
differential bearing bore. At this point the dial indi­
cator should read the same as
mark
etched on the
pinion head. If the reading
does
not agree, add or
remove the shims behind the bearing cup until
the readings agree.

k.
The end of each pinion is etched with a plus
(+) number, a minus (—) number or zero (0)
number to indicate the
best
running position for
each particular gear set.
This
dimension is con­
trolled by shimming behind the inner pinion bear­ ing cup. Therefore if a pinion is etched (-f-2), this
pinion would require .002"
less
shims than a pinion
etched "0". By removing shims the mounting dis­
tance is increased which is just what a (+2) etch­
ing indicates. Or if a pinion is etched (—2), add
.002" more shims than would be required if the
pinion were etched "0". By adding .002" shims the mounting distance is decreased which is just what

a
(—2) etching indicates.

Note:
To increase the dial reading decrease shims;
to decrease the dial reading increase shims.

Example:
With a dial reading of minus .001" and
a
pinion marking of plus .002" remove .003" shims
to obtain a higher dial reading of plus .002"

I.
If the original ring and pinion set is to be re­
used, measure the old pinion shim pack and build a
new shim pack to this dimension. Collect shim pack
saved from teardown. Measure each shim separately 297