Download Group 3 - Rear Axle

GROUP 3
A,
REAR AXLE
CONTENTS
REAR AXLE A S S E M B L Y (BW) RING GEAR
REAR AXLE NOISE DIAGNOSIS
S E R V I C E DIAGNOSIS
5
2
1
Page
SPECIFICATIONS
SURE-GRIP DIFFERENTIAL
TIGHTENING R E F E R E N C E
..
..
23
19
23
SERVICE DIAGNOSIS
Condition
REAR WHEEL NOISE
..
Possible Cause
(a) Wheel L o o s e .
(b) S p a l l e d w h e e l bearing c u p or c o n e .
(c) Defective, brinelled w h e e l bearing.
(d) E x c e s s i v e axle shaft e n d play.
(e) B e n t or s p r u n g axle shaft flange.
SCORING OF
DIFFERENTIAL GEARS
AND PINIONS
(a) Insufficient lubrication.
(b) Improper grade of lubricant.
(c) E x c e s s i v e s p i n n i n g of one w h e e l .
TOOTH BREAKAGE (RING
GEAR AND PINION)
(a) Overloading.
(b) Erratic c l u t c h operation.
(c) Ice-spotted p a v e m e n t s .
(d) Improper
REAR AXLE NOISE
adjustment.
(a) Insufficient lubricant.
Correction
(a) Tighten loose wheel nuts.
(b) C h e c k rear w h e e l bearings. If s p a d e d
or worn, r e p l a c e .
(c) Defective or brinelled bearings m u s t
be r e p l a c e d . C h e c k rear axle shaft
e n d play.
(d) R e a d j u s t axle shaft e n d play.
(e) R e p l a c e bent or s p r u n g axle shaft.
(a) R e p l a c e s c o r e d gears. S c o r i n g m a r k s
on the p r e s s u r e f a c e of gear teeth
or in the bore are c a u s e d by instant a n e o u s f u s i n g of the mating s u r f a c e s .
S c o r e d g e a r s should be replaced. Fill
rear axle to required c a p a c i t y with
proper lubricant.
S e e Specification s e c t i o n .
(b) R e p l a c e s c o r e d gears. I n s p e c t all
g e a r s a n d bearings for possible d a m age. C l e a n out a n d refill axle to required c a p a c i t y with proper lubricant.
S e e Lubrication s e c t i o n .
(c) R e p l a c e s c o r e d gears. I n s p e c t all
gears, pinion bores a n d shaft for
scoring, or bearings for possible d a m age. S e r v i c e a s n e c e s s a r y .
(a) R e p l a c e g e a r s . E x a m i n e other g e a r s
and bearings for possible d a m a g e .
R e p l a c e parts a s needed. Avoid Overloading.
(b) R e p l a c e gears, a n d examine remaining parts for possible damage. Avoid
erratic c l u t c h operation.
(c) R e p l a c e g e a r s . E x a m i n e remaining
parts for possible damage. R e p l a c e
parts a s required.
(d) R e p l a c e g e a r s . E x a m i n e other parts
for possible damage. Make s u r e ring
gear a n d pinion b a c k l a s h is correct.
(a) Refill rear axle with correct amount
of the proper lubricant. S e e S p e c i f i c a tion s e c t i o n . Also c h e c k for leaks a n d
correct a s n e c e s s a r y .
(b) Improper ring gear a n d pinion adjust- (b) C h e c k ring gear a n d pinion tooth
ment.
contact.
(c) U n m a t c h e d ring gear and pinion.
(c) R e m o v e u n m a t c h e d ring gear a n d
pinion. R e p l a c e with a new m a t c h e d
gear a n d pinion s e t .
(d) Worn teeth on ring gear or pinion.
(d) C h e c k teeth on ring gear a n d pinion
for contact. If n e c e s s a r y , replace with
new m a t c h e d s e t .
3-2
A
REAR AXLE
Condition
^
Possible Cause
Correction
(e) End play in drive pinion bearings.
(e) Adjust drive pinion bearing preload.
(f) Side play in differential bearings.
(f) Adjust differential bearing preload.
(g) Sure-Grip Differential moan and chat- (g) Drain and flush lubricant. See prater,
cedure in Sure-Grip section of Group
LOSS OF L U B R I C A N T
(b)
(c)
(d)
(e)
(f)
(g)
OVERHEATING OF UNIT
(a) Drain excess lubricant by removing
filler plug and allow lubricant to level
at lower edge of filler plug hole.
(b) Replace worn oil seals with new ones.
Worn axle shaft oil seals.
Prepare new seals before replacement.
(c) Repair or replace housing as required.
Cracked rear axle housing.
(d) Replace worn drive pinion oil seal
Worn drive pinion oil seal.
with a new one.
(e) Replace worn or scored companion
Scored and worn companion flange.
flange and oil seal.
(f) Clean breather thoroughly.
Clogged breather.
Loose carrier housing bolts or hous- (g) Tighten bolts or cover screws to specifications and fill to correct level
ing cover screws.
with proper lubricant.
(a) Lubricant level too high.
(a) Refill rear axle.
(b) Drain, flush and refill rear axle with
correct amount of the proper lubricant. See Specification Section.
(c) Readjust bearings.
(c) Bearings adjusted too tightly.
(d) Check gears for excessive wear or
(d) Excessive wear in gears.
scoring. Replace as necessary.
(e) Insufficient ring gear t o pinion clear- (e) Readjust ring gear and pinion backlash and check gears for possible
ance.
scoring.
(a) Lubricant level too low.
(b) Incorrect grade of lubricant.
REAR AXLE NOISE DIAGNOSIS
Most rear axle failures are relatively simple t o
locate and correct, although rear axle noise is a l i t t l e
more difficult to diagnose and make the necessary repairs. The most essential p a r t of rear axle service is
proper diagnosis of the problem.
A l l rear axles are noisy t o a certain degree. Gear
noise is usually associated w i t h older axles, b u t this
is not always true. New axles can also be noisy i f they
are not properly adjusted or lack lubrication. Usually
when new i m p r o p e r l y set gears are noisy; the disturbi n g noise cannot be "adjusted o u t " once the gears are
broken i n . Recent experience has shown that axle
gears can often be readjusted to reduce excessive gear
noise, i f they have been operated at n o r m a l break-in
speeds f o r less than 500 miles. Regardless of what
you've heard to the contrary, noisy gears w i l l not get
quieter w i t h added mileage . . . they w i l l stay the same
or get worse.
Slight axle noise heard only at certain speeds o r
under remote conditions must be considered n o r m a l .
A x l e noise tends to " p e a k " at v a r y i n g speeds and the
noise is i n no way indicative of trouble i n the axle.
I f axle noise is present i n an objectionable f o r m ,
loud or at a l l speeds, an effort should be made t o isolate the noise as being i n one p a r t i c u l a r u n i t of the ve-
h i d e . Many noises, reported as coming f r o m the rear
axle actually originate f r o m other sources such as
tires, road surfaces, wheel bearings, engine, transmission, exhaust, propeller shaft vibration, universal j o i n t
noise or body d r u m m i n g . A thorough and careful
check should be made to determine the source of the
noise before any disassembly and teardown of the rear
axle is attempted.
The complete isolation of noise i n any one u n i t requires considerable s k i l l and previous experience.
E l i m i n a t i n g certain type noises often baffle even the
most experienced personnel. Often such practices as
raising t i r e pressures to eliminate t i r e noise, listening
f o r the noise at varying speeds under different load
conditions such as; drive, float and coast, and under
certain highway conditions, t u r n i n g the steering wheel
f r o m left t o r i g h t to detect wheel bearing noise, w i l l
aid even the beginner i n detecting certain alleged axle
noises. A x l e noises n o r m a l l y f a l l into two categories:
gear noise and bearing noise.
To make a good diagnostic check f o r rear axle
noise, a thorough road test is necessary. Select a level
smooth blacktop o r asphalt road. This w i l l reduce tire
noise and body d r u m m i n g . Drive the car far enough
to thoroughly w a r m up the axle to n o r m a l operating
temperature.
Drive the car and note speed at w h i c h noise occurs.
A
—
Then stop car and, w i t h clutch disengaged or automatic transmission i n neutral, r u n engine slowly u p
and down t h r o u g h engine speeds, corresponding to
car speed at which noise was most pronounced, t o determine i f i t is caused by exhaust roar, o r other engine conditions. Repeat, w h i l e engaging and disengaging clutch (transmission i n neutral), to determine
i f noise can only be isolated b y removing propeller
shaft and operating transmission i n high).
T I R E NOISE
Tire noise is often mistaken for rear axle noise even
though the noisy tires may be located on t h e f r o n t
wheels. Tires that are unbalanced or w o r n unevenly
or have surfaces of non-skid type design, or w o r n i n a
saw tooth fashion are usually noisy and often produce
noises that seem to originate i n the rear axle.
Tire noise changes w i t h different road surfaces, but
rear axle noise does not. Inflate a l l tires to approximately 50 pounds pressure (for test purposes only).
This w i l l materially alter noise caused by tires, but
w i l l not affect noise caused b y rear axle. Rear axle
noise usually ceases when coasting at speeds under
30 miles per hour; however, t i r e noise continues, but
w i t h lower tone, as car speed is reduced. Rear axle
noise usually changes when comparing drive and
coast, but tire noise remains about the same.
Distinguish between t i r e noise and differential noise
by noting i f noise varies w i t h various speeds or sudden
acceleration and deceleration; exhaust and axle noise
show variations under these conditions while t i r e noise
remains constant and is more pronounced at speeds of
20 to 30 miles per hour. F u r t h e r check f o r t i r e noise
by d r i v i n g car over smooth pavements or d i r t roads
(not gravel) w i t h tires at n o r m a l pressure. I f noise is
caused by tires, i t w i l l noticeably change or disappear
and reappear w i t h changes i n road surface.
FRONT W H E E L BEARING NOISE
Loose or rough f r o n t wheel bearings w i l l cause
noise which may be confused w i t h rear axle noises;
however, f r o n t wheel bearing noise does not change
when comparing drive and coast. L i g h t application of
brake while holding car speed steady w i l l often cause
wheel bearing noise t o diminish, as this takes some
weight off the bearing. F r o n t wheel bearings may be
easily checked for noise by j a c k i n g u p the wheels and
spinning them, also by shaking wheels to determine i f
bearings are loose.
Rear suspension rubber bushings and spring insulators help to dampen out rear axle noise when p r o p e r l y
and correctly installed. Check t o see that no metallic
interference exists between the springs and springs
hangers, shackles or " U " bolts. Metal to metal contact
REAR AXLE
3-3
at those points may result i n telegraphing road noise
and n o r m a l axle noise w h i c h w o u l d not be objectionable i f properly installed and tightened to specifications.
GEAR NOISE
A b n o r m a l gear noise can be recognized easily because i t produces a cycling tone and w i l l be very
pronounced t h r o u g h the speed range i n which i t occurs. Gear noise may be developed under one or more
of t h e following conditions, " d r i v e " , " r o a d l o a d " ,
" f l o a t " o r "coast". Gear noise usually tends t o peak
i n a narrow speed range or ranges. Gear noise is more
prominent between 30 t o 40 m p h and 50 t o 60 m p h .
A b n o r m a l gear noise is quite rare and i f present i t
usually originates f r o m scoring of the r i n g and drive
pinion gear as a result of insufficient o r improper
lubrication of the axle assembly. The differential side
gears and pinions very seldom cause trouble as they
are only under loads when the rear wheels travel at
different speeds; such as when t u r n i n g corners.
When objectionable axle noise is heard, note the
d r i v i n g condition and speed range. Remove the differential and carrier f r o m the axle housing on the 8-3/4"
axle. Perform a tooth contact p a t t e r n check to determine i f the best possible pattern has been obtained.
I f pattern is f o u n d to be unacceptable, reshim and
adjust to obain the best possible pattern. I f after readjustment noise s t i l l persists, replace w i t h new gear set.
PRE-DISASSEMBLY
INVESTIGATION
A close examination of the rear axle assembly p r i o r
to disassembly can reveal valuable i n f o r m a t i o n as t o
the extent and type of repairs or adjustments necessary. This i n f o r m a t i o n coupled w i t h the road test results w i l l provide a basis f o r determining the degree
of disassembly required. Since the most frequent
causes of axle noise are improper backlash or different i a l bearing preload, or both, a few simple adjustments may be a l l that is necessary to correct the complaint.
Therefore, before disassembly the following checks
should be made; drive gear and p i n i o n backlash,
pinion bearing preload, and tooth contact p a t t e r n and
these results recorded and analyzed. I t is felt that
these measurements and t h e i r results w i l l aid you i n
m a k i n g the necessary repairs t o the axle assembly.
BEARING NOISE (DRIVE PINION AND
DIFFERENTIAL)
Defective or damaged bearings generally produce a
rough g r o w l or g r a t i n g sound, that is constant i n pitch
and varies w i t h t h e speed of t h e vehicle. This fact
w i l l allow you t o diagnose between bearing noise and
gear noise.
3-4
REAR AXLE
A
:
D r i v e p i n i o n bearing noise r e s u l t i n g f r o m defective
or damaged bearings can usually be identified b y a
constant rough sound. F r o n t pinion bearing noise is
usually most pronounced on "coast", whereby rear
pinion bearing is loudest on " d r i v e " . Pinion bearings
are r o t a t i n g at a higher rate of speed than the differential side bearings or the axle shaft bearings. These
particular noises can be picked up best by road testing
the vehicle i n question on a smooth road (black top).
However, extreme caution should be t a k e n not to confuse t i r e noise w i t h bearing or gear noise. I f doubt
should exist t i r e treads should be examined f o r i r r e g u larities that w i l l often produce such noise.
Differential bearing noise w i l l usually produce a
constant rough tone w h i c h is much slower than t h e
noise caused by the p i n i o n bearings.
and pinion n u t torque must be reset to original settings upon reinstallation.
BACKLASH CLUNK
Excessive clunk on acceleration and deceleration
can be caused by anyone of the following items or a
combination; (excessive clearance between) (1) Differential p i n i o n shaft to differential case, (2) Axle shaft
to differential side gear splines, (3) Differential side
gear hub to differential case counterbore, (4) Different i a l side gear to pinion, (5) W o r n t h r u s t washers, (6)
Drive gear backlash. Measure and inspect components
and replace as required and/or adjust to proper specifications.
ENGINE AND TRANSMISSION
REAR W H E E L BEARING NOISE
Defective or damaged rear wheel bearings produce
a vibration or g r o w l w h i c h continues w i t h car coasting
and transmission i n neutral. A brinneled rear wheel
bearing causes a w h i r r i n g noise. Spalled rear wheel
bearings n o r m a l l y produce a noise similar to a growl,
created f r o m either flaked or pitted rollers or bearings
races. Unless the damage is severe, rear axle bearing
noise is seldom heard above 30 m p h .
To differentiate between wheel bearings and gear
noise, road test the vehicle on a smooth road (blacktop) at m e d i u m and low speed. W i t h traffic p e r m i t t i n g ,
swerve the vehicle sharply r i g h t to left. I f the noise i n
question is caused by wheel bearings, i t w i l l usually
increase when the vehicle is swerved and w i l l probably be coming f r o m the bearing on the loaded side.
I f the noise i n question cannot be isolated an inspection of bearings w i l l be necessary.
KNOCK AT LOW S P E E D S
Low speed knock is usually caused b y b r i n n e l e d
universal joints or differential side gear h u b t o counterbore clearance being too great. Inspect and replace
universal j o i n t or differential case and side gear as
required.
DRIVE-LINE SNAP
A snap on a sudden start, either f o r w a r d or reverse,
may be caused b y a loose companion flange. Remove
the propeller shaft and flange and reinstall 180 degrees f r o m o r i g i n a l position. Pinion bearing preload
NOISE
Sometimes noises w h i c h seem to originate i n t h e
rear axle are actually that of the engine or transmission. To diagnose w h i c h u n i t is actually causing the
noise, observe the approximate vehicle speed and conditions under which t h e noise is most pronounced;
stop the vehicle i n a quiet place t o avoid any interferi n g noises. W i t h engine r u n n i n g and transmission i n
neutral, r u n engine slowly up and down t h r o u g h engine speeds corresponding to approximate car speed
at w h i c h the noise was most pronounced. I f a noise
similar is produced i n this manner i t usually can be
assumed that the noise was caused by the engine or
transmission and not that of the rear axle.
P R O P E L L E R SHAFT
VIBRATION
Objectional vibrations at high speed (65 M P H or
higher) may be caused by a propeller shaft that is out
of balance o r w o r n universal joints. Out of balance
may be due to a damaged or bent shaft.
To determine whether propeller shaft is causing
the v i b r a t i o n i n question; road test the vehicle t h r o u g h
speed range and note speed at which v i b r a t i o n is most
pronounced. Shift transmission into lower gear range
and drive car at same engine speed as when v i b r a t i o n
was most pronounced i n direct drive and note any
effect on vibration.
I f the vibration is s t i l l present at the same engine
speed, whether i n direct drive or i n the lower gear,
since the propeller shaft speed varies, this cannot be
the fault. I f the v i b r a t i o n decreases or is eliminated i n
the lower gear, then propeller shaft is at fault and
should be rebalanced or replaced.
REAR AXLE
A-
REAR AXLE ASSEMBLY ZVa
3-5
RING GEAR
INDEX
Page
Axle S h a f t s and B e a r i n g s . . . . . . . . . . . . . . . . . . . . . .
Axle S h a f t End Play
Differential a n d Carrier (Removal)
Differential a n d Carrier (Installation)
Differential C a s e
Drive Gear and Pinion B a c k l a s h
Gear Tooth Contact Pattern . . . . . . . . . . . . . . . . . . . .
Lubrication
Pinion Bearing Cup Installation . . . . . . .
.
6
9
10
18
11
17
17
18
13
Page
Pinion Bearing Preload and Pinion Depth of
M e s h Setting U s i n g Tool C-758-D4 . . . . . . . . . . . .
Large S t e m Pinion Depth of Mesh
Depth of Mesh
Setting Without U s i n g Tool C-758-D4
R e a r Axle Housing
R e m o v a l and R e p l a c e m e n t of Drive Pinion
F l a n g e and Oil S e a l in V e h i c l e
14
14
16
9
18
GENERAL INFORMATION
The 8 - 3 / 4 " Rear A x l e Assembly shown i n (Fig. 1),
is a semi-floating type and may be divided into four
subassemblies; flanged axle drive shafts w i t h related
parts (Fig. 2.) differential w i t h drive gear, drive p i n i o n
w i t h carrier, and the axle housing. Servicing of the
above mentioned subassemblies, w i t h exception of the
axle housing may be performed w i t h o u t removing the
complete rear axle assembly f r o m the vehicle.
Gear ratio identification numbers w i l l be stamped
on a metal tag and attached b y means of the rear
axle housing-to-carrier bolt.
Some 8 - 3 / 4 " large stem differential and carrier assemblies have incorporated a collapsible spacer w h i c h
bears against the i n n e r races of the f r o n t and rear
bearing. This collapsible spacer is used to establish
preload on the p i n i o n bearings.
A d j u s t m e n t of pinion depth of mesh is obtained by
placing a machined shim between the p i n i o n head and
the rear p i n i o n bearing cone.
The differential bearings are larger on both the conventional and Sure-Grip Differentials and are not i n terchangeable w i t h previous years bearings.
The Sure-Grip Differential is available as optional
equipment i n the 8 - 3 / 4 " rear axle assembly. The new
Sure-Grip Differential is of a two piece construction
similar to the old type and is completely interchangeable w i t h the previous type and w i l l be serviced as a
complete assembly only. Refer to the "Sure Grip Diff e r e n t i a l " Section of the Axle Group for the servicing
procedure.
ADJUSTER
SHAFT
BUMPER
HOUSING
TEE
SCREW
WASHER
RIGHT
BOLT
GASKET
SUPPORT
'
N
*r*
BOLT
"-GASKET
OIL
NUT
SHAFT
SEAL
STUD
COLLAR
CARRIER A N D C A P
GASKET
FLANGE
L
E
F
T
OIL SEAL
RETAINER'
Fig. 1—8-3/4" Rear Axle
Assembly
NK967B
3-6
REAR
A
AXLE
SHOULD T H E REAR A X L E BECOME SUBMERGED
IN W A T E R , T H E L U B R I C A N T MUST B E C H A N G E D
IMMEDIATELY TO AVOID T H E POSSIBILITY O F
E A R L Y A X L E F A I L U R E R E S U L T I N G FROM CONTAMINATION O F T H E L U B R I C A N T B Y W A T E R
DRAWN INTO T H E V E N T .
SERVICE PROCEDURES
use of a torch in the removal of the axle shaft collars
or bearings is an unsafe practice, because heat is fed
into the axle shaft bearing journal and thereby weakC A U T I O N : I t is absolutely necessary that anytime an
ens this area.
axle assembly is serviced, and the axle shafts are
(1) Position axle shaft bearing r e t a i n i n g collar on a
loosened and removed, the axle shaft gaskets and
inner axle shaft oil seals must be replaced.
heavy vise o r anvil a n d using a chisel, c u t deep
The service procedures f o r t h e removal a n d i n - grooves into retaining collar at 90° intervals (Fig. 6).
This w i l l enlarge bore of collar and p e r m i t i t to be
stallation of the axle shaft bearings and collars differ
d r i v e n off of axle shaft.
on the I m p e r i a l , due to a change i n the material hardness of the collar. I t w i l l be necessary that this pro(2) Remove bearing roller retainer flange b y
cedure be followed to assure that axle shaft is n o t c u t t i n g off lower edge w i t h a chisel (Fig. 7).
damaged i n any way d u r i n g the servicing.
(3) G r i n d a section off flange of i n n e r bearing
cone (Fig. 8) and remove bearing rollers (Fig. 9).
(4) P u l l bearing roller retainer down as f a r as posRemoval
(All
models)
(1) W i t h wheels removed, remove clips h o l d i n g
ADAPTER
BLOCKS BEARING
REMOVING SP-5020
SP-5021
brake d r u m o n axle shaft studs and remove brake
drum.
SCREWS
\
X
SP-5026
(2) Using access hole i n axle shaft flange, remove
>*4
retainer nuts, the r i g h t shaft w i t h threaded adjuster
i n retainer plate w i l l have a lock under one of the
»
studs that should be removed at this time.
ADAPTER
WASHERS
SP-5015 OR SP-5168
(3) A t t a c h axle shaft remover Tool C-3971 (Fig. 3)
SP-320
use Tool C-3971 and adapter SP-5168 on I m p e r i a l only,
to axle shaft flange and remove axle shaft. Remove
brake assembly and gaskets.
(4) Remove axle shaft o i l seal f r o m axle housing
using Tool C-637 (Fig. 4).
m v.
(5) Wipe axle housing seal bore clean and install
a new axle shaft o i l seal using Tool C-839 (Fig. 5).
AXLE SHAFTS AND BEARINGS
y
>
Disassembly
(All Models
except
Imperial)
C A U T I O N : To prevent the possibility of damaging
axle shaft seal surface, slide protective sleeve SP5041 over the seal surface next to bearing collar.
C A U T I O N : Under no circumstances should axle shaft
collars or bearings be removed using a torch. The
/
\
R:NG-3LOCK
SLEEVE
SP-5041
HOLDING SP-5017
Fig. 3-7oof Set C-3971
FLANGE
ADJUSTER
TOOL
i
SHAFT
i!£!Jl
C
LOCK
SEAL
Fig. 2—Axle Shaft
J
P
/
COLLAR
BEARING
NK59A
Disassembled
x
S
Fig. 4—Removing Axle Shaft Oil Seal
NK360A
REAR AXLE
Fig. 5-lnstalling
3-7
Axle Shaft Oil Seal
Fig. 8—Flange Ground Off Inner Cone
SLEEVE
SLEFV-_
SP-5041
SP-5CM]'
BEARING
'
ROLLER
MM
/4*4
Fig. 6—Notching Bearing Retainer
NK127A
Collar
sible and cut w i t h a pair of side cutters and remove
(Fig. 10).
(5) Remove roller bearing cup a n d protective
sleeve SP-5041 f r o m axle shaft.
C A U T I O N : Sleeve SP-5041 should not be used as a
protector for the seal journal when pressing off the
bearing cone, as it was not designed for this purpose.
(6) To avoid scuffing seal j o u r n a l when bearing
NK358
Fig. 9—Removing Bearing
Rollers
cone is being removed, i t should be protected b y
single wrap of .002 thickness shimstock held i n place
by a rubber band (Fig. 11).
(7) Remove t h e bearing cone using Tool C-3971
(Fig. 3). Tighten bolts of tool alternately u n t i l cone is
removed (Fig. 12).
SLEEVE
SP-5041
.
..
"
4
V
SLFEVc
SP-5041
U ft
s.
••••
"A •
4
f 1
i
NX359
Fig. 7—Removing Roller
Retainer
Fig. 10—Cutting Out Roller Bearing
Retainer
NN124A-
Fig. I 1 — Seal Journal
Protection
(8) Remove seal i n bearing retainer plate and replace w i t h new seal.
Assembly
(1) Install retainer plate and seal assembly on axle
shaft.
(2) Lubricate wheel bearings w i t h Multi-Purpose
Grease N L G I Grade 2 EP.
(3) Install a new axle shaft bearing cup, cone and
collar on shaft using Tool C-3971 (Fig. 13) and t i g h t e n
bolts of tool alternately u n t i l bearing and collar are
seated properly.
(4) Inspect axle shaft seal j o u r n a l f o r scratches and
polish w i t h #600 crocus cloth i f necessary.
Disassembly
(Imperial)
C A U T I O N : Under no circumstances should axle shaft
collars or bearings be removed using a torch. The
use of a torch in the removal of the axle shaft collars
or bearings is an unsafe practice, because heat is
fed into the axle shaft bearing journal and, thereby
weakens this area.
(1) Slide protective sleeve SP-5041 over the seal
Fig. 12—Removing Bearing Cone with Tool C-3971
NK362
Fig. 13—Installing New Bearing and Collar
surface next to bearing collar and tape i n place. This
w i l l prevent the possibility of seal surface being
damaged d u r i n g the c u t t i n g of r o l l e r retainer, g r i n d i n g of collar and inner bearing race and s p l i t t i n g of
collar.
(2) Remove bearing r o l l e r retainer flange by c u t t i n g
off lower edge w i t h a chisel (Fig. 7).
(3) G r i n d axle shaft collar i n one position to approximate thickness of protective sleeve SP-5041.
A t same time g r i n d a portion of inner bearing race
so bearing rollers can be removed (Fig. 14).
(4) Position axle shaft bearing retaining collar on
a heavy vise or anvil and using a chisel, cut a groove
into collar at position that y o u previously ground.
Collar should split and, which i n t u r n w i l l enlarge
bore and p e r m i t collar to be driven off of axle shaft.
(5) Remove bearing rollers at ground section of
i n n e r bearing race (Fig. 9).
(6) P u l l bearing roller retainer down as far as
possible and cut w i t h a pair of side cutters and remove (Fig. 10).
Fig. 14—Collar and Inner Race Ground Prior to
Removal (Imperial)
•REAR AXLE
A(7) Remove roller bearing cup and protective sleeve
SP-5041 f r o m axle shaft.
C A U T I O N : Sleeve SP-5041 should not be used as a
protector for the seal journal when pressing off the
bearing cone, as it was not designed for this purpose.
(8) To avoid scuffing seal j o u r n a l when bearing
cone is being removed, i t should be protected by a
single wrap of .002 thickness shimstock held i n place
by a rubber band (Fig. 11).
(9) Remove bearing cone using Tool C-3971 and
adapter SP-5168. Tighten bolts of tool alternately
u n t i l cone is removed (Fig. 12).
(10) Remove seal i n bearing retainer plate and replace w i t h new seal.
Assembly
(Imperial)
(1) Install retainer plate and seal assembly on axle
shaft.
(2) Lubricate wheel bearings w i t h Multi-Purpose
Grease N L G I Grade 2 E.P. or equivalent.
(3) Install a new axle shaft bearing cup, cone on
axle shaft using Tool C-3971 and adapter SP-5168 (Fig.
13) and tighten bolts of tool alternately u n t i l bearing
is seated properly. Repeat same step for installing
the collar.
(4) Inspect axle shaft seal j o u r n a l for scratches
and polish w i t h #600 crocus cloth i f necessary.
Installation
(1) Clean axle housing flange face and brake support plate thoroughly. Install a new rubber asbestos
gasket on axle housing studs, followed by brake support plate assembly on left side of axle housing.
(2) A p p l y a t h i n coating of Multi-Purpose Grease,
N L G I Grade 2 E.P. or equivalent to the outside diameter of the bearing cup p r i o r to installing i n the beari n g bore. This operation is necessary as a corrosion
preventative.
(3) Install foam gasket on the studs of axle housing
and carefully slide axle shaft assembly t h r o u g h o i l
seal and engage splines i n differential side gear.
(4) Tap end of axle shaft l i g h t l y w i t h a nonmetallic mallet to position axle shaft bearing i n housi n g bearing bore. Position retainer plate over axle
housing studs. Install retainer nuts and t i g h t e n 30-35
foot-pounds. Start by tightening bottom n u t .
(5) Repeat step (1) for r i g h t side of axle housing.
(6) Back off threaded adjuster of r i g h t axle shaft
assembly u n t i l inner face of adjuster is flush w i t h
inner face of retainer plate. Carefully slide axle shaft
assembly t h r o u g h o i l seal and engage splines i n differential side gears.
(7) Repeat step (4).
AXLE SHAFT END
PLAY
C A U T I O N : When setting axle shaft end play, both
3-9
rear wheels must be off the ground, otherwise a false
end play setting will occur.
(1) Using a d i a l indicator mounted on the left
brake support (Fig. 15), T U R N T H E ADJUSTER
CLOCKWISE U N T I L B O T H W H E E L BEARINGS ARE
SEATED A N D T H E R E IS ZERO E N D P L A Y I N T H E
A X L E SHAFTS. B A C K OFF T H E ADJUSTER COUNTERCLOCKWISE A P P R O X I M A T E L Y FOUR NOTCHES TO ESTABLISH A N A X L E S H A F T END P L A Y
OF .008-.018 I N C H .
(2) Tap end of left axle shaft l i g h t l y w i t h a nonmetallic mallet to seat r i g h t wheel bearing cup
against adjuster, and rotate axle shaft several revolutions so that a true end play reading is indicated.
(3) Remove one retainer plate n u t , install adjuster
lock. I f tab on lock does not mate w i t h notch i n adjuster, t u r n adjuster slightly u n t i l i t does. Install n u t
and tighten 30-35 foot-pounds.
(4) Recheck axle shaft end play. I f i t is not w i t h i n
the tolerance of .008-.018 inch, then repeat adjustment procedure.
(5) Remove dial indicator and install brake d r u m ,
d r u m retaining clips and wheel.
REAR AXLE HOUSING
Removal
(1) Raise vehicle and support body at f r o n t of rear
springs.
(2) Block brake pedal i n the up position using a
wooden block.
(3) Remove rear wheels.
(4) Disconnect hydraulic brake hose at connection
on left side of underbody.
(5) Disconnect p a r k i n g brake cable.
To maintain proper drive line balance when reassembling, make scribe marks on the propeller shaft
universal j o i n t and the p i n i o n flange before removal.
(6) Disconnect propeller shaft at differential yoke
NK128
Fig. 15—Measuring Axle Shaft End Play
3-10
A
REAR AXLE
and secure i n an u p r i g h t position to prevent damage
to f r o n t universal j o i n t .
(7) Remove shock absorber f r o m spring plate studs
and loosen rear spring " U " bolt nuts and remove " U "
bolts.
(8) Remove the assembly f r o m vehicle.
Installation
(1) W i t h body of vehicle supported at f r o n t of rear
springs, position the rear axle assembly spring seats
over the spring center bolts.
(2) I n s t a l l spring " U " bolts and t i g h t e n nuts to 45
foot-pounds and install shock absorbers on s p r i n g
plate studs. (DO NOT OVER T I G H T E N " U " B O L T
NUTS.)
(3) Install propeller shaft (match scribe marks on
propeller shaft universal j o i n t and p i n i o n flange).
T i g h t e n clamp screws to 15 foot-pounds.
(4) Connect p a r k i n g brake cable.
(5) Connect hydraulic brake hose, bleed and adjust
brakes.
(6) Install rear wheels.
(7) I f carrier was removed f r o m axle housing duri n g the removal operation, fill axle w i t h proper
amount and type of lubricant; see "Specifications" i n
L u b r i c a t i o n section Group " 0 " .
Welding
Rear Axle
Housing
The axle housing should be completely disassembled i f i t is to be welded w i t h arc welding equipment. I t is also possible to weld the assembled housi n g w i t h gas welding equipment, i f precaution is
taken to protect gaskets and heat treated parts.
DIFFERENTIAL
AND
CARRIER
Removal
(1) Remove flanged axle drive shafts.
(2) Disconnect rear universal j o i n t and support
propeller shaft up and out of the way to prevent damage to the f r o n t universal j o i n t .
(3) Remove the rear axle lubricant.
(4) Loosen and remove the carrier-to-housing attaching nuts and l i f t the carrier assembly f r o m axle
housing.
jit
mm
• 1
KP19
Fig. 16—Checking for Runout and Zero End Play
(2) Rotate drive gear several complete revolutions
while noting t o t a l indicator reading. M a r k drive gear
and differential case at point of m a x i m u m r u n o u t . The
m a r k i n g of differential case w i l l be very useful later
i n checking differential case r u n o u t . Total indicator
reading should be no more than .005 inch. I f r u n o u t
exceeds .005 i n c h the differential case may be damaged, and a second reading w i l l be required after
drive gear has been removed. This operation is covered d u r i n g " D i f f e r e n t i a l Disassembly". Remove d i a l
indicator.
(3) W i t h Tool C-3281 hold companion flange and
remove drive p i n i o n n u t and Belleville washer.
(4) Install companion flange remover Tool C-452
and remove flange (Fig. 17).
(5) Using a screwdriver and hammer, remove the
drive p i n i o n o i l seal f r o m the carrier.
(6) While holding one hand over nose end of carrier, i n v e r t carrier i n stand. The f r o n t p i n i o n bearing
cone, shim pack and bearing spacer (where used) w i l l
drop f r o m carrier.
(7) A p p l y identifying punch marks on differential
bearing pedestals of carrier, differential bearing caps
and bearing adjusters for reassembly purposes (Fig.
18).
TOOL
Disassembly
Side play and r u n o u t check taken d u r i n g disassembly w i l l be very useful i n reassembly.
(1) Mount carrier i n Stand DD-1014 and attach dial
indicator Tool C-3339 to differential carrier flange i n
a position so pointer of indicator squarely contacts
back face of r i n g gear (Fig. 16). W i t h a screw d r i v e r
positioned between bearing cap and differential case
flange, then using a p r y i n g m o t i o n determine i f side
play is present. I f side play is evident, remove adjuster
lock and loosen adjuster slightly and retighten adjuster sufficiently to eliminate side play.
TOOL"
KP5B
Fig. 17—Removing Compvmlcn friange
A
REAR AXLE
Fig. 18—Marking Bearing Caps and Adjusters
(8) Remove both differential bearing adjuster lock
screws and locks.
(9) W i t h a 3/4 inch socket, loosen bearing cap bolts
(one on each side) and back off bearing adjusters
slightly using spanner wrench Tool C-406A; to remove differential bearing preload. Remove bearing
cap bolts, caps and bearing adjusters.
(10) Remove differential and r i n g gear assembly
w i t h bearing cups. Differential bearing cups must be
kept w i t h respective bearing cones.
(11) Remove drive pinion and rear bearing assembly f r o m carrier.
Rear Pinion Bearing
Removal
(1) Remove drive pinion rear bearing f r o m large
stem pinion w i t h Tool C-293 and four (4) No. 37 plates
(Fig. 19).
(2) Using a flat end brass d r i f t , remove f r o n t and
rear p i n i o n bearing cups.
DIFFERENTIAL
CASE
i n a vise equipped w i t h soft jaws (brass).
(2) Remove drive gear bolts. BOLTS A R E L E F T
H A N D T H R E A D . W i t h a non-metallic hammer, tap
drive gear loose f r o m differential case p i l o t a n d
remove.
(3) I f drive gear r u n o u t exceeded .005 i n c h i n
step 2 (under " C a r r i e r Disassembly"), recheck the case
as follows: I n s t a l l differential case and respective
bearing cups i n carrier.
(4) Install bearing caps, cap bolts and bearing adjusters. Tighten bearing cap bolts down l i g h t l y and
screw i n both adjusters w i t h spanner wrench Tool
C-406A.
(5) Tighten cap bolts and adjusters sufficiently t o
prevent any side play i n bearings.
(6) Attach a d i a l indicator Tool C-3339 t o carrier
flange so pointer of indicator squarely contacts drive
gear surface of differential case flange between outer
edge flange and drive gear bolt holes (Fig. 20).
(7) Rotate differential case several complete revolutions while n o t i n g total indicator reading. This
reading must not exceed .003 i n c h runout. I f r u n o u t
is i n excess of .003 inch, differential case must be replaced. In a case where the runout does not exceed
.003 inch it is often possible to reduce the runout by
positioning the drive gear 130° from point of maximum runout when reassembling drive gear on differential case.
(8) W i t h a flat nose d r i f t and hammer, remove differential pinion shaft lock p i n f r o m back side of drive
gear flange. (The hole is reamed only part way
through, making i t necessary to remove lock p i n f r o m
one direction.)
(9) W i t h a brass d r i f t and hammer, remove differential p i n i o n shaft and axle drive shaft thrust
block.
(10) Rotate differential side gears u n t i l each differential p i n i o n appears at large opening of case.
Disassembly
(1) Mount differential case and r i n g gear assembly
Fig. 19—Removing Drive Pinion Rear
Bearing
3-11
Fig. 20—Checking Drive Gear Mounting
Flange Face Runout
3-12
REAR AXLE
A
SHAFT
THRUST
WASHER
BEARING
BEARING
I
I
DIFFERENTIAL CASE
PIN
CONE V
/
J
/
\
j
A N D
BEARING
LOCK
ADJUSTER
SPACER
CAP
-
j
/
FLANGE
CONE
COLLAPSIBLE
CUP
I
J
AND LOCK WASHER
CONE
DRIVE
^' ^^J
%
BEARING
BOLT
\
CARRIER
\
\
/
SEAL \
\
\
y
GEAR
P 1 N 1 G N
WASHER
GUARD
PLUG
^-CAP
SIDE G E A R
\
THRUST W A S H E R
i
j
THRUST
PINION
SIDE
\
\
WASHER
^THRUST
LOCK
BLOCK
THRUST WASHER
WASHER
"—ADJUSTER
BEARING
CONE
BOLT AND LOCK WASHER
GEAR
KP1D
WASHER
Fig. 2 1 —Differential Carrier Assembly (Large Stem Tapered
Remove each p i n i o n and thrust washer at that time.
(11) Remove both differential side gears and t h r u s t
washers.
Cleaning
and Inspection
(Fig* 2 1 J
(1) Clean a l l parts i n a fast evaporating m i n e r a l
spirits or a d r y cleaning solvent and w i t h the except i o n of bearings, d r y w i t h compressed air.
(2) Inspect differential bearing cones, cups and
rollers f o r p i t t i n g , spalling o r other visible damage. I f
replacement is necessary, remove bearing cones f r o m
differential case w i t h Tool C-293 and adapter plates
No. 43 (Fig. 22).
(3) Inspect differential case f o r elongated or enlarged p i n i o n shaft hole. T h e machined thrust
washer surface areas a n d counterbores must be
smooth and w i t h o u t metal deposits or surface imperfections. I f any of the above conditions exist, satisfact o r y correction must be made or t h e case replaced.
Inspect case f o r cracks or other visible damage w h i c h
m i g h t render i t unfit for f u r t h e r service.
(4) Inspect differential p i n i o n shaft f o r excessive
wear i n contact area of differential pinions. Shaft
should be smooth and r o u n d w i t h no scoring or metal
pickup.
(5) Inspect differential side gears and pinions, they
should have smooth teeth w i t h a u n i f o r m contact patt e r n w i t h o u t excessive wear or broken surfaces. The
differential side gear and p i n i o n t h r u s t washers
should be smooth and free f r o m any scoring or metal
pickup.
(6) Inspect axle shaft t h r u s t block f o r excessive
wear or visible damage. The wear surface on t h e
opposite ends of the blocks, must be smooth.
(7) Inspect differential p i n i o n shaft lock p i n f o r
Pinion)
damage or looseness i n case. Replace p i n or case as
necessary.
(8) Inspect drive gear and p i n i o n f o r w o r n or
chipped teeth or damaged attaching bolt threads. I f
replacement is necessary, replace b o t h the drive gear
and drive p i n i o n as they are available i n matched sets
only.
(9) Inspect drive p i n i o n bearing cones, cups a n d
rollers f o r p i t t i n g , spalling, excessive wear, or other
vns
ccoo
KP8
Fig, 22—Removing lOif^erentM
Bearings
-REAR AXLE
visible damage. I f inspection reveals that either are
unfit for f u r t h e r service, replace both cup and cone.
(10) Inspect differential carrier for cracks or other
visible damage which w o u l d render i t unfit f o r
further service. Raised metal on the shoulder of bearing cup bores i n c u r r e d i n removing pinion cups
should be flattened by use of a flat nose punch.
(11) Inspect drive pinion f o r damaged bearing
journals and m o u n t i n g shim surface o r excessively
w o r n splines. I f replacement is necessary, replace
both the drive pinion and drive gear as they are
available i n matched sets only.
(12) Inspect companion flange f o r cracks, w o r n
splines, pitted, rough or corroded o i l seal contacting
surface. Repair or replace companion flange as necessary.
ASSEMBLY
LUBRICATE A L L PARTS B E F O R E ASSEMBLY WITH
L U B R I C A N T A S S P E C I F I E D IN (LUBRICATION
GROUP "O")
(1) Install thrust washers on differential side gears
and position gears i n case.
(2) Place t h r u s t washers on both differential pinions and t h r o u g h large window of differential case,
mesh the pinion gears w i t h t h e side gears, having
pinions exactly 180 degrees opposite each other.
(3) Rotate side gears 90 degrees t o align pinions
and thrust washers w i t h differential pinion shaft
holes i n case.
(4) F r o m pinion shaft lock p i n hole side of case,
insert slotted end of pinion shaft t h r o u g h case, and
the conical thrust washer, and just t h r o u g h one of the
pinion gears.
(5) Install thrust block t h r o u g h side gear h u b , so
that slot is centered between the side gears.
(6) While keeping a l l of these parts i n proper
alignment, push pinion shaft into case u n t i l locking
p i n hole i n pinion shaft is i n exact alignment w i t h its
respective hole i n case. Install pinion shaft lock p i n
through hole i n case f r o m pinion shaft side of drive
gear flange. The contacting surfaces of the drive gear
and differential case flange must be clean and free of
all burrs.
(7) Using an Arkansas stone, relieve the sharp edge
of the chamfer on the inside diameter of the r i n g gear
(Fig. 23). This is very important otherwise during the
installation of ring gear on differential case, the sharp
edge will remove metal from the pilot diameter of
case and can get imbedded between differential case
flange and gear; causing gear not to seat properly.
(8) Position drive gear on differential case pilot,
aligning threaded holes of drive gear w i t h those i n
differential case flange.
(9) Insert
drive
gear
screws
(LEFT H A N D
THREADS) t h r o u g h case flange and into drive gear.
3-13
NU403
Fig. 23—Stoning Chamfer on Ring Gear
A f t e r a l l cap screws are properly started, tap drive
gear against differential case flange w i t h a nonmetallic mallet.
(10) Position u n i t between brass jaws of a vise and
alternately t i g h t e n each cap screw to 55 foot-pounds.
(11) Position each differential bearing cone on h u b
of differential case (taper away f r o m drive gear) and
w i t h installing Tool C-4086 install bearing cones.
A n arbor press may be used i n conjunction w i t h i n stalling tool.
C A U T I O N : Never exert pressure against the bearing
cage, since this would damage the bearing.
PINION BEARING CUP INSTALLATION
(1) Position pinion bearing cups squarely i n bores
of carrier. Assemble Tool C-758-D4 (Fig. 24) b y placi n g spacer SP-5387 followed b y rear pinion bearing
cone over m a i n screw of tool and inserting i t into
carrier f r o m gear side.
(2) Place f r o n t pinion bearing cone over m a i n
S L E E V E SP-2920
G A U G E B L O C K SP-528 O R S P - 3 2 5 0 8 / "
v> A N D 9 % " A X L E
WRENCH
A %
CROSSBORE ARBOR
3
4
mf
•» 1
c r V w
SCREW
V
r \
V x
S
P
W A S
A
C
E
R
HER
SP
\
' \
COMPRESSION
S L E E V E SP-535
SPACER
SPACER
WASHER
^ W A S H E R
SP-1371
4
561
8%"AXLE
SP-5183 9 % " A X L E
^
SP-538
SLEEVE
SP-1370
~
SP-3639
SP-2921 O R 5 3 8 7
8 / " AXLE
SP-5184 9 / " A X L E
3
4
3
CENTRALIZING
WASHER
y&
SP-534
Jj?
4
T
SLEEVE
'SP-1682
SPACER
S P
"
1 7 3 0
PINION
—
COMPRESSION
LOCATING
T
N U T SP-533
SPACER
SPACER
SP-2919
SP-539
N
U
4
Fig. 24—Rear Axle Setting Gauge Tool C-758-D4
1
8
A
3-14
REAR AXLE
•—»
A
—
screw of tool followed by compression sleeve SP-535,
centralizing washer SP-534, and m a i n screw n u t SP533. H o l d compression sleeve w i t h the companion
flange holding Tool C-3281 and tighten n u t (Fig. 25)
allowing tool to rotate as n u t is being tightened i n
order not to b r i n n e l bearing cone or cups. Do not
remove tool after installing cups.
SP-561
PINION LOCATING WASHER
PINION BEARING PRELOAD AND DEPTH OF
MESH SETTING USING TOOL C-758-D4
The 8-3/4" large stem differential and carrier assembly has incorporated a collapsible spacer w h i c h
bears against the inner races of the f r o n t and rear
bearings. This collapsible spacer is used to establish
pinion bearing preload. The large stem pinion requires
the depth of mesh adjustment first while pinion beari n g preload is the last operation performed.
The position of the drive pinion w i t h respect to the
drive gear (depth of mesh) is determined by the locat i o n of the bearing cup shoulders i n the carrier and
by the p o r t i o n of the p i n i o n i n back of the rear bearing. The thickness of the rear p i n i o n bearing mounti n g shim suitable for the carrier can be determined
by using Tool C-758-D4.
DEPTH OF MESH
(Large Stem Pinion)
Inspect differential bearing cups and cones, carrier
for g r i t and d i r t or other foreign material. Clean ail
parts i n fast evaporating m i n e r a l spirits or a dry
cleaning solvent and w i t h the exception of bearing
cones, d r y w i t h compressed air. Front Pinion Bearing
Cone and Cup Must Never Be Reused Under Any Circumstances.
(1) Assemble spacer SP-5387 to main section of
t o o l followed by spacer SP-1730. Install rear p i n i o n
bearing cone over spacer SP-1730 and against spacer
SP-5387 (Fig. 26).
(2) Insert assembly i n t o carrier and install f r o n t
pinion bearing cone over t o o l shaft and i n its proper
ft
NY168C
Fig. 26-Tool C-758-D4 Installed in Housing
(8-3/4 Large Stem Pinion)
position i n bearing cup. Install tool spacer, tool t h r u s t
washer and tool n u t on shaft.
(3) W i t h nose of carrier up, place flange holding
Tool C-3281 on compression sleeve. A l l o w assembly
to rotate while tightening n u t to not more than 25-50
foot-pounds. Always make sure bearing cones are
lubricated with hypoid gear lubricant.
(4) T u r n tool several complete revolutions i n both
directions to p e r m i t bearing rollers to seat. A f t e r
bearing rollers are properly seated, check bearing
preload by r o t a t i n g tool w i t h an inch-pound torque
wrench. The correct bearing preload should be f r o m
20-30 inch-pounds for new bearings.
(5) W i t h proper bearing preload set, invert carrier
i n stand and install gauge block SP-528 or SP-3250 to
the m a i n screw attaching i t w i t h A l l e n screw securely
(Fig. 27). The flat p o r t i o n of gauge block should be
facing differential bearing pedestals.
(6) Position tool arbor SP-561 i n differential beari n g pedestals of carrier (Fig. 28). Center the arbor so
that an approximate equal distance is maintained at
both ends. Position differential bearing caps and attaching bolts on carrier pedestals, and insert a piece
iP^
far'
Fig. 25—Seating Bearing Cup in Carrier
KP13B
Housing
Fig. 27—Installing Gauge Blo<sk on fool
A
REAR AXLE
3-15
(10) Reverse carrier i n stand so n u t of t o o l is i n upr i g h t position. Loosen compression n u t , and support
lower p o r t i o n of tool i n carrier w i t h one hand, remove tool n u t , centering washer a n d compression
sleeve. Lower tool down and out of carrier.
(11) Remove front pinion bearing cone f r o m carr i e r housing.
(12) W i t h stem of drive pinion facing u p , add rear
pinion bearing mounting shim you selected on p i n i o n
stem.
rig. 28—Installing Arbor in Carrier
of .002 inch shim stock between arbor and each cap.
Tighten cap bolts to 10 foot-pounds.
(7) Select a rear pinion bearing m o u n t i n g shim
which w i l l f i t between cross arbor and gauge block.
This fit must be snug but not too t i g h t (similar to the
p u l l of a feeler gauge. (Fig. 29). This shim is then
used i n d e t e r m i n i n g the correct thickness shim f o r
installation.
(8) To select a shim for installation, read the marking on end of p i n i o n head (—0, — 1 , — 2 , + 1 , + 2 ,
etc). When m a r k i n g is — , (minus) add that amount t o
the thickness of shim selected i n step (7). When the
marking is + (plus), subtract that amount. Example:
With a shim .036 inch thick and a pinion marked — 2 ,
install a shim .038 inch thick (.036 + .002 = .038).
Example: W i t h a shim .036 inch thick and a p i n i o n
marked + 2 , install a washer .034 inch thick, (.036
— .002 = .034) or when a shim .036 inch t h i c k is too
loose and .038 inch too thick, use .036 inch shim.
Treat other pinion markings i n a similar manner.
Shims are available i n one thousands of an i n c h
increments.
(9) Remove differential bearing caps and remove
tool arbor f r o m carrier.
fig. 29—Determining Spacer
Thickness
PINION BEARING PRELOAD
(Large Stem Pinion)
(1) Position rear p i n i o n bearing cone on pinion
stem (small side away f r o m pinion head). Make certain that the contacting surfaces of selected shim, rear
bearing cone and pinion head are perfectly clean and
free of any foreign particles.
(2) Lubricate front and rear pinion bearing cones
w i t h hypoid gear lubricant. Install rear p i n i o n bearing
cone onto pinion stem, using Tool C-3095, press beari n g cone into place. A n arbor press may be used i n
conjunction w i t h tool.
(3) Insert drive pinion and bearing assembly u p
t h r o u g h carrier and install collapsible spacer followed
by front pinion bearing cone on pinion stem. Install
companion flange using Tool C-496 or DD-999 and
holding Tool C-3281. This is necessary i n order t o
properly install front pinion bearing cone on stem due
to interference fit. Remove tool f r o m pinion stem.
C A U T I O N : D u r i n g the installation of the f r o n t pinion
bearing be careful not to collapse the spacer.
(4) A p p l y a l i g h t coat of sealer in seal bore of carr i e r casting and install drive pinion oil seal into carrier
using Tool C-4109 or C-3980 (double l i p synthetic rubber oil seal) or Tool C-3656 (single l i p leather oil seal).
The proper tool must be used i n order to position the
seal the proper depth into the carrier casting.
(5) W i t h pinion supported i n carrier, install anticlang washer on pinion stem. Install companion flange
w i t h installing Tool C-496 or DD-999 and h o l d i n g Tool
C-3281.
(6) Remove tools and install Belleville washer (convex side of washer up) and pinion nut.
(7) H o l d universal j o i n t flange w i t h h o l d i n g Tool
C-3281 and tighten p i n i o n n u t to remove end play i n
pinion, while rotating the pinion to insure proper
bearing seating.
(8) Remove holding tool and rotate p i n i o n several
complete revolutions i n both directions to p e r m i t beari n g rollers to seat.
(9) Tighten pinion n u t to 170 foot-pounds and measure pinion bearing preload b y rotating p i n i o n using
an inch-pound torque wrench. The correct preload
specifications are 20-35 inch-pounds f o r new bear-
3-16
REAR AXLE
ings or 10 inch-pounds over t h e original i f the
old rear pinion bearing is being reused. Correct bearing preload readings can only be obtained
w i t h nose of carrier i n u p r i g h t position. Continue
tightening of p i n i o n n u t i n small increments and
checking p i n i o n bearing preload u n t i l proper preload
is obtained. Bearing preload should be u n i f o r m d u r i n g
complete revolution. A preload reading that varies
d u r i n g rotation indicates a b i n d i n g condition which
has to be corrected. The assembly is unacceptable i f
final pinion n u t torque is below 170 foot-pounds or
pinion bearing preload is not w i t h i n the correct specifications.
NOTE: UNDER NO CIRCUMSTANCES SHOULD T H E
P I N I O N N U T B E B A C K E D OFF T O LESSEN PRELOAD. I F THIS IS DONE A N E W COLLAPSIBLE
SPACER MUST B E I N S T A L L E D A N D N U T RET I G H T E N E D U N T I L PROPER PRELOAD IS OBTAINED.
-
A
being careful not to collapse the spacer.
A p p l y a l i g h t coat of sealer to drive pinion o i l seal
and carrier casting bore and install drive p i n i o n o i l
seal w i t h Tool C-4109 or C-3980 (synthetic rubber seal
or Tool C-3656 (leather seal). Install anti-clang washer
and universal j o i n t flange, Belleville washer (convex
side of washer up) and nut. Tighten the pinion n u t t o
170 foot-pounds and using an inch-pounds torque
wrench rotate the pinion t o determine preload. The
correct preload specifications are 20-30 inch-pounds
for new bearings or 10 inch-pounds over the original
i f the old rear pinion bearing is being reused. I f preload is not correct, continue to tighten pinion n u t i n
small increments and checking preload u n t i l preload
on pinion bearings is correct. A m i n i m u m of 170 footpounds of torque is required on pinion nut. Under no
circumstances should the pinion nut be backed off to
lessen preload. If this is done a new pinion bearing
collapsible spacer must be installed and nut retightened until proper preload is obtained.
DEPTH OF MESH
(Without
Using Tool C-758-D4)
I f the differential assembly was satisfactorily quiet
before being disassembled, the drive pinion must be
assembled w i t h new pinion bearings. I f replacement parts are installed, a complete readjustment is
necessary; the proper thickness shim must be selected
and installed. The drive gear and pinion are manufactured and lapped i n matching sets and are available
i n matched sets only. The adjustment position i n
which the best tooth contact is obtained is marked on
the end of the p i n i o n head.
To obtain the proper p i n i o n setting i n r e l a t i o n t o
the drive gear, the correct thickness m o u n t i n g shim
must be selected before t h e drive p i n i o n is installed
i n the carrier. The p i n i o n bearing m o u n t i n g shims are
available i n one thousands increments f r o m .020-.038
inch. To select the proper thickness shim, proceed as
follows: I t w i l l be noted that the head of the drive
pinion is marked w i t h a plus ( + ) o r minus (—) sign
followed by a number ranging f r o m 1 to 4, or zero (0)
marking.
I f the o l d and new p i n i o n have t h e same m a r k i n g
and i f t h e o r i g i n a l bearing is being reused, use a
m o u n t i n g shim of the same thickness. B u t i f the o l d
p i n i o n is m a r k e d zero (0) and t h e new p i n i o n is
m a r k e d + 2 , t r y a .002 i n c h t h i n n e r shim. I f the new
pinion is m a r k e d — 2 , t r y a .002 i n c h thicker shim.
Pinion Bearing Preload
(Large
Stem)
A f t e r selecting the correct pinion bearing m o u n t i n g
shim and installing i t behind the rear p i n i o n bearing
cone proceed as follows: I n s t a l l the p i n i o n assembly
into the carrier. Install the new collapsible spacer followed b y new f r o n t p i n i o n bearing cone on p i n i o n
stem. Press f r o n t p i n i o n bearing cone on p i n i o n stem,
Installation
of Differential
and Ring Gear in
Carrier
(1) H o l d i n g differential and r i n g gear assembly
w i t h bearing cups on respective bearing cones, caref u l l y install the assembly into carrier.
(2) Install differential bearing caps, on respective
sides, m a k i n g certain that identification marks o n
caps correspond w i t h those on carrier. Install cap bolts
and tighten bolts of each cap by hand.
(3) Install differential bearing adjusters, on respect i v e sides, m a k i n g certain that identification marks
correspond. Screw adjuster i n by hand. N o attempt
should be made t o apply any excessive pressure at
this time.
(4) Using spanner wrenches Tool C-406A to square
bearing cups w i t h bearing cone, t u r n adjusters " I N "
u n t i l cups are properly square w i t h bearings and end
play is eliminated w i t h some backlash existing between the drive gear and pinion (Fig. 30).
KP20A
Fig. 30—Adjusting Differential
Bearings
-REAR AXLE
(5) Tighten one differential bearing cap b o l t o n
each side to 85-90 foot-pounds.
DRIVE GEAR AND PINION
PATTERN
C L O S E TO
3-17
CENTER
BACKLASH
Correct drive gear and p i n i o n backlash w h e n
properly set is .006 t o .008 i n c h at point of m i n i m u m
backlash. Rotate drive pinion and r i n g gear several
revolutions i n both directions i n order to seat the bearing rollers. This is necessary before setting backlash.
(1) A t t a c h a dial indicator Tool C-3339 to carrier
flange so pointer of indicator is squarely contacting
one drive gear tooth (drive side) (Fig. 31).
(2) Measure backlash between drive gear and pinion at four positions, approximately 90 degrees apart.
A f t e r point of least backlash has been determined,
m a r k drive gear. Do not rotate drive gear from point
of least backlash until all adjustments have been
completed.
(3) Using Tool C-406A (spanner wrench) t u r n b o t h
bearing adjusters equally ( i n same direction) u n t i l
backlash between drive gear and p i n i o n is .0005 t o
.0015 inch. This backlash variation is given to permit
alignment and installation of the bearing adjuster
lock, lockwasher and attaching screw. The adjuster
must only be turned in a clockwise direction and
under no circumstances should be backed off.
(4) Install adjuster lock o n bearing cap, back-face
side of drive gear. Tighten lock screw to 15 to 20
foot-pounds.
Differential
Bearing
Preload
(1) T u r n bearing adjuster (tooth side of drive gear)
(Fig. 32) i n a notch at a time (notch referred t o is the
adjuster lock holes) u n t i l backlash between drive gear
and p i n i o n is a m i n i m u m of .006 to .008 inch. This
w i l l preload differential bearings and establish correct backlash.
KP21
Fig. 31—Measuring Backlash between
Gear and Pinion
Drive
HEEL E N D - D a , y z
S I D E (CONVEX)
HEEL E N D — C O A S
SIDE
T
(CONCAVE/
N
R
]
°
8
Fig. 32—Desired Tooth Contact Under Light Load
(2) Tighten the remaining two differential bearing
cap bolts to 85-90 foot-pounds.
(3) Install remaining adjuster lock, lockwasher and
attaching screw. Tighten to 15-20 foot-pounds.
GEAR TOOTH CONTACT
PATTERN
The gear tooth contact pattern w i l l disclose whether
the correct rear p i n i o n bearing m o u n t i n g shim has
been installed and the drive gear backlash set properly. Backlash between the drive gear and p i n i o n must
be maintained w i t h i n the specified limits u n t i l correct
tooth contact pattern is obtained.
(1) A p p l y a t h i n film of r e d or white lead on both
the drive and coast side of the drive gear teeth. Rotate drive gear one complete revolution i n b o t h directions while load is being applied w i t h a r o u n d bar or
screwdriver between the carrier casting and different i a l case flange. This action w i l l leave a distinct contact pattern on both the drive and coast side of t h e
drive gear teeth.
(2) Observe the contact p a t t e r n on the drive gear
teeth and compare w i t h those i n figures 32, 33 and 35
to determine i f pattern is p r o p e r l y located. W i t h
pinion depth of mesh and gear backlash set properly,
your contact pattern should resemble that i n (Fig. 32).
Notice that the correct contact pattern is w e l l centered
on both drive and coast sides of the teeth. When tooth
contact patterns are obtained b y hand, they are apt
to be rather small. Under the actual operating load,
however, the contact area increases.
(3) I f after observing the contact p a t t e r n y o u find
i t resembles that i n (Fig. 33), the drive pinion is
too f a r away f r o m centerline of the r i n g gear, t h e
contact pattern w i l l appear h i g h on the heel on drive
side and h i g h on toe on coast side. To correct this
type tooth contact pattern, increase the thickness of
the rear p i n i o n bearing m o u n t i n g spacer (Fig. 34),
w h i c h w i l l cause the h i g h heel contact on drive side
to lower and move toward the toe; the h i g h toe contact on coast side w i l l lower and move toward the
heel.
3-18
-A
REAR AXLETHICKER S P A C E R
(6) Install rear wheels
pounds.
NEEDED
a n d t i g h t e n t o 65 foot-
LUBRICATION
.4.
'••rV.W
HEEL END-DRIVE
SIDE (CONVEX) "*
HEEL E N D - C O A S T
SIDE (CONCAVE)
N
R
1
"
Fig. 33—incorrect Tooth Contact Pattern
(Increase Spacer Thickness)
(4) I f after observing the contact p a t t e r n y o u find
i t resembles that i n (Fig. 35), t h e drive p i n i o n is
too close to the r i n g gear, the p a t t e r n w i l l appear low
on the toe on d r i v e side and l o w heel contact on coast
side. To correct this type t o o t h contact p a t t e r n , decrease t h e thickness of the rear p i n i o n bearing mounti n g spacer (Fig. 36), w h i c h w i l l cause t h e l o w toe
contact on d r i v e side t o raise and move t o w a r d t h e
heel; l o w heel contact on coast side w i l l raise a n d
move t o w a r d the toe.
D I F F E R E N T I A L AND CARRIER
Installation
(1) Thoroughly clean the gasket surfaces of the carr i e r and rear axle housing.
(2) Using a new gasket, install the c a r r i e r assembly
i n t o the axle housing. T i g h t e n the carrier to axle housi n g nuts to 45 foot-pounds.
(3) Refer to " I n s t a l l a t i o n of Rear A x l e Shaft," w h e n
installing and setting axle shaft end play.
(4) Install propeller shaft (match scribe marks on
propeller shaft universal j o i n t and p i n i o n flange).
T i g h t e n clamp screws to 15 foot-pounds.
(5) Remove wooden block f r o m under brake pedal
and bleed and adjust brakes.
PATTERN MOVES TOWARD CENTER
AND DOWN
/ TOE / ~ \
Anticipated Temperature Range
Viscosity G r a d e
SAE 90
SAE 80
S A E 75
Above — 10°F.
As low as — 30°F.
Bleow — 3 0 ° F .
REMOVAL AND R E P L A C E M E N T OF DRIVE
PINION FLANGE AND OIL S E A L IN V E H I C L E
On large stem carriers w h i c h use t h e collapsible
spacer to obtain p i n i o n bearing preload, the f o l l o w i n g
procedure f o r t h e removal and replacement of t h e
drive p i n i o n flange and p i n i o n o i l seal must be followed to assure that the proper bearing preload is
maintained i n the axle assembly. I f this procedure is
not followed i t could result i n a premature failure of
the axle.
(1) Raise vehicle on hoist and make scribe marks
on propeller shaft universal j o i n t , drive p i n i o n flange
and end of p i n i o n stem.
(2) Disconnect propeller shaft at p i n i o n flange and
secure i n an u p r i g h t position to prevent damage to
f r o n t universal j o i n t .
(3) Remove t h e rear wheels and brake drums to
prevent any drag o r a possible false preload reading
could occur.
THINNER SPACER NEEDED
•N^-COAST
DE (CONCAVE)
Refill axle assembly w i t h Multipurpose Gear L u b r i cant, as defined b y MIL-L-2105B (API GL-5) should be
used i n a l l rear axles w i t h conventional differentials;
Chrysler H y p o i d L u b r i c a n t part number 2933565 is an
o i l of this type and is recommended o r an equivalent
be used.
I n Sure-Grip axles on all 1970 Vehicles i t is recommended that only Chrysler H y p o i d L u b r i c a n t p a r t
number 2933565 o r an equivalent be used. This l u b r i cant, recommended f o r conventional differentials too,
contains special additives to provide proper different i a l d u r a b i l i t y and performance.
N
Fig. 34—Effect on Tooth Contact Pattern as
Spacer Thickness is Increased
R
2
0
0
HEEL E N D - D R I V E
SIDE (CONVEX)
^jgaEND-COAST
SIDE iCONCAVEi
Fig. 35—Incorrect Tooth Contact Pattern
(Decrease Spacer Thickness)
NR201
A
REAR AXLE
(4) Using inch-pound torque w r e n c h C-685 measure
pinion bearing preload by r o t a t i n g p i n i o n w i t h handle
of wrench floating, read the torque w h i l e wrench is
moving t h r o u g h several complete revolutions and record. This operation Is very Important because preload must be carefully reset when reassembling.
(5) W i t h Tool C-3281 hold companion flange and
remove drive pinion n u t and Belleville washer.
(6) Install companion flange remover Tool C-452
and remove flange. Lower rear of vehicle to prevent
lubricant leakage.
(7) Using a screwdriver and hammer, remove the
pinion oil seal f r o m the carrier and clean the o i l seal
seat.
(8) Check splines on p i n i o n shaft stem to be sure
they are free of b u r r s or are not w o r n badly. I f burrs
are evident remove them using crocus cloth by working i n a rotational motion. Wipe the p i n i o n shaft clean.
(9) Inspect companion flange f o r cracks, w o r n
splines, pitted, rough or corroded o i l seal contacting
surface. Repair or replace companion flange as necessary.
(10) A p p l y a l i g h t coat of sealer i n seal bore of carr i e r and install drive pinion o i l seal into carrier using
Tool C-4109 o r C-3980 (Double l i p synthetic rubber o i l
seal) or Tool C-3656 (single l i p leather o i l seal). The
proper tool must be used i n order to properly position
the seal the correct depth i n t o the carrier casting.
(11) Position companion flange on p i n i o n stem being careful to match scribe marks made previously
before removal.
(12) Install companion flange w i t h installing Tool
C-496 or DD-999 and holding Tool C-3281.
(13) Remove tool and install Belleville washer (convex side of washer up) and p i n i o n n u t .
(14) H o l d universal j o i n t flange w i t h h o l d i n g Tool
C-3281 and tighten pinion n u t t o 170 foot-pounds. Rotate pinion several complete revolutions t o assure
that bearing rollers are properly seated. Using an
inch-pound torque wrench C-685 measure p i n i o n
bearing preload. Continue t i g h t e n i n g p i n i o n n u t and
PATTERN M O V E S
HEEL
SIDE
INWARD AND
END—DRIVE
(CONVEX)
UP
'-:EEL E N D - COAST
SIDE
3-19
(CONCAVE)
NR202
Fig. 36—Effect on Tooth Contact Pattern as Spacer
Thickness is Decreased
checking preload u n t i l preload is at the original established setting y o u found i n step 4. Under no circumstances should the preload be more than 5 inchpounds over the established setting found at time of
checking i n step 4 of procedure.
Bearing preload should be u n i f o r m d u r i n g a complete revolution. A preload reading that varies d u r i n g
rotation indicates a b i n d i n g condition which has to be
corrected. The assembly is unacceptable i f final pinion
nut torque is below 170 foot-pounds or p i n i o n bearing
preload is not w i t h i n the correct specifications.
C A U T I O N : Never back off the pinion nut to lessen
pinion bearing preload. If the desired preload is exceeded a new collapsible spacer must be installed and
nut retightened until proper preload is obtained. In
addition, the universal joint flange must never be hammered on, or power tools used.
(15) Install propeller shaft (match scribe marks on
propeller shaft universal point and p i n i o n flange).
Tighten clamp screws to 15 foot-pounds.
(16) Install t h e rear brake drums and wheels and
tighten nuts 65 foot-pounds.
(17) Raise the vehicle to a level position so axle assembly is at correct r u n n i n g position and check l u b r i cant level. A d d the correct type of l u b r i c a n t required
to b r i n g lubricant to proper level.
SURE-GRIP DIFFERENTIAL
INDEX
Page
Installing Sure Grip Differential and
Carrier Assembly
Lubrication
Sure Grip Differential Identification . . . . .
Sure Grip Differential Noise . . . . . . . . . . . . . . . . . . . .
GENERAL
22
22
20
20
Sure Grip Differential
Removal
Cleaning & Inspection
Assembly . . . . . .
Testing Sure Grip Differential
Page
21
22
22
22
21
INFORMATION
A new Sure-Grip differential being offered
special equipment option i n t h e 8-3/4" rear
(Fig. 1).
as a
axles
The Sure-Grip differential design is basic and simple and consists of a t w o piece case construction and
is completely interchangeable w i t h t h e conventional
3-20
REAR AXLE'
A
*'
Fig. 1—Sure-Grip
NU404
Differential
differential and also the previous type Sure-Grip differential (Fig. 2).
A conventional differential allows t h e d r i v i n g
wheels to rotate at different speeds while d i v i d i n g the
d r i v i n g torque equally between them. This function
is ordinarily desirable and satisfactory. However, t h e
total d r i v i n g torque can be no more than double the
torque at the lower-traction wheel. W h e n traction conditions are n o t the same f o r both d r i v i n g wheels, a
portion of the available traction cannot be used.
The SURE-GRIP differential allows t h e d r i v i n g
wheel w i t h the better traction condition to develop
more d r i v i n g torque than the other wheel, so that the
total d r i v i n g torque can be significantly greater than
w i t h a conventional differential.
SURE-GRIP is not a locking differential. I n n o r m a l
d r i v i n g conditions the controlled i n t e r n a l f r i c t i o n is
easily overcome d u r i n g cornering and t u r n i n g so that
the d r i v i n g wheels can t u r n at different speeds. Ex-
SERVICE
treme differences i n traction conditions at the d r i v i n g
wheels may p e r m i t one wheel to spin.
SURE-GRIP has been engineered t o p e r f o r m its
specialized functions w i t h m i n i m u m effect on n o r m a l
vehicle operations.
The cone clutch SURE-GRIP differentials are similar
to corresponding 8-3/4 conventional differentials except f o r the incorporation of the helix-grooved cones
that clutch the side gears to the differential case. The
grooves assure m a x i m u m lubrication of t h e clutch
surface d u r i n g operation. T h e cone brakes and side
gears are statically spring preloaded t o provide an
i n t e r n a l resistance to the differential action w i t h i n the
differential case itself. This i n t e r n a l resistance assures an adequate amount of p u l l while under extremely low tractive conditions such as m u d , snow or
ice when encountered at one of the rear wheels.
D u r i n g torque application to t h e axle, the i n i t i a l
spring loading of the cone brakes is supplemented by
the gear separating forces between the side gears and
differential pinions w h i c h progressively increases the
f r i c t i o n i n the differential. I t should be remembered
that the Sure-Grip differential is not a positive locki n g type and w i l l release before excessive d r i v i n g
force can be applied to one wheel.
SURE-GRIP D I F F E R E N T I A L IDENTIFICATION
Identification of sure-grip differential assembly can
easily be made b y l i f t i n g both rear wheels off t h e
ground and t u r n i n g them. I f both rear wheels t u r n i n
the same direction simultaneously, t h e vehicle is
equipped w i t h a Sure-Grip Differential. Another
means of identification is b y removing the filler p l u g
and using a flashlight to look t h r o u g h the filler p l u g
hole to identify the type of differential case.
PROCEDURES
S U R E - G R I P D I F F E R E N T I A L NOISE
(Chatter—Moan)
Noise complaints related t o rear axles equipped
w i t h cone-clutch SURE-GRIP should be checked t o
determine t h e source of the noise. I f a vehicle r i d e
check produces t h e noise i n turns b u t n o t straight
ahead, the probable cause is incorrect o r dissipated
rear axle lubricant. The following d r a i n i n g and flushi n g procedure has been established f o r the Sure-Grip
Differential before i t is removed f r o m the vehicle and
replaced.
C A U T I O N : When servicing vehicles equipped with
Sure-Grip differentials do not use the engine to rotate
axle components unless both rear wheels are clear off
the ground. Sure-Grip equipped axles can exert a
significant driving force if one wheel is in contact with
floor and could cause the vehicle to move.
(1) W i t h lubricant of rear axle assembly at operati n g temperature raise car on hoist so rear wheels are
free t o t u r n .
(2) Loosen and remove fill p l u g and using a suction
gun remove as much of the old l u b r i c a n t as possible.
(3) F i l l axle to proper level w i t h multi-Purpose Hypoid Gear Lubricant Part Number 2933565 or equivalent. Reinstall fill p l u g and tighten.
(4) Start engine of vehicle and engage i n gear and
r u n on hoist w i t h rear wheels free t o t u r n at approximately 40 M P H f o r ten (10) minutes. This thoroughly
circulates the l u b r i c a n t and brings i t to operating temperature.
(5) Stop vehicle and remove the fill p l u g and using
a suction gun remove as m u c h of the l u b r i c a n t as possible.
REAR AXLE
3-21
DIFFERENTIAL
CASE
PINIONS
SIDE GEARS
CONE CLUTCH
COIL SPRING
LUBRICATION
POCKET
LUBRICATION
GROOVES
NU405
Fig. 2-Sme-Grip
Differential
(6) Refill axle to proper level w i t h multi-Purpose
Hypoid Gear Lubricant Part N u m b e r 2933565 or
equivalent. Reinstall fill p l u g and tighten.
(7) Lower vehicle on hoist and r e t u r n to customer
to drive and evaluate f o r approximately 100 miles to
determine i f lubricant corrects the noise complaint.
I f after the vehicle is driven approximately 100
miles and the noise condition is s t i l l evident, remove
the differential and carrier assembly and replace the
Sure-Grip Differential. The Sure-Grip Differential and
the internal parts are serviced as an assembly only.
(Schematic)
p e r f o r m i n g properly and should be removed and replaced. The Sure-Grip Differential and i n t e r n a l parts
are serviced as a complete assembly only. Under no
circumstances should the differential be removed and
disassembled and reinstalled.
SURE-GRIP DIFFERENTIAL
C A U T I O N : During removal and installation of axle
shafts, DO NOT rotate one axle shaft unless both are
TESTING S U R E - G R I P D I F F E R E N T I A L
The Sure-Grip differential can be checked t o determine i f its performance is satisfactory w i t h o u t removi n g the differential and carrier assembly f r o m the vehicle.
(1) Position vehicle on hoist w i t h engine off and
the transmission selector lever i n p a r k i f automatic or
i n l o w gear i f manual.
(2) A t t e m p t to rotate wheel b y applying t u r n i n g
force w i t h hands g r i p p i n g t i r e tread area (Fig. 3).
(3) I f y o u find i t extremely difficult, i f not impossible to manually t u r n either wheel, y o u can consider
the sure-grip differential to be p e r f o r m i n g satisfactorily. I f you find i t relatively easy t o continuously
t u r n either wheel smoothly then t h e differential is not
NU406
Fig. 3—Testing Sure-Grip Differential
Effectiveness
3-22
A
REAR AXLE
in position. Rotation of one axle shaft without the
other in place may result in misalignment of the two
spline segments with which the axle shaft spline engages, and will necessitate difficult realignment procedures when shaft is installed.
Removal
Follow the same procedure outlined under conventional differential removal.
Cleaning
and
Inspection
(1) Clean t h e Sure-Grip differential assembly i n a
fast evaporating m i n e r a l spirits or a d r y cleaning solvent and w i t h exception of bearings, d r y w i t h compressed air.
(2) Inspect differential bearing cones, cups and r o l l ers f o r p i t t i n g , spalling o r other visible damage. I f
replacement is necessary, remove bearing cones f r o m
differential case using Tool C-293 and adapter plates
No. 43.
(3) Visually inspect differential case f o r cracks or
other visible damage w h i c h m i g h t render i t unfit f o r
f u r t h e r service.
Assembly
I f d u r i n g cleaning and inspection t h e differential
bearings were f o u n d to be unfit f o r f u r t h e r use and
were removed follow this procedure for installation of
new bearings.
(1) Position each differential bearing cone o n h u b
of differential case (taper away f r o m drive gear) and
w i t h installing Tool C-4086, install bearing cones. A n
arbor press may be used i n conjunction w i t h installing
tool. C A U T I O N : Never exert pressure against the
bearing cage, since this would damage the bearing.
(2) I f the r i n g gear was removed f r o m the sure-grip
differential case o r is being replaced w i t h a new r i n g
gear for any reason, new n y l o k drive gear screws must
be installed.
IMPORTANT: The procedure f o r installing t h e r i n g
gear on differential case must be followed so the r i n g
gear seats on the differential case properly.
(3) Using an Arkansas stone, relieve t h e sharp
edge of the chamfer on the inside diameter of the r i n g
gear (Fig. 23 i n 8-3/4" A x l e section of this group).
This is very i m p o r t a n t , otherwise d u r i n g the installation of r i n g gear on differential case, the sharp edge
w i l l remove metal f r o m the p i l o t diameter of case and
can get imbedded between differential case flange and
gear; causing gear not to seat properly.
(4) Position r i n g gear on differential case pilot
aligning threaded holes of r i n g gear w i t h those i n
differential case flange.
(5) Insert drive gear screws (left hand threads)
through case flange and into r i n g gear. A f t e r all cap
screws are properly started, tap r i n g gear against differential case flange w i t h a non-metallic mallet.
(6) Position differential case u n i t between brass
jaws of a vise and alternately tighten each cap screw
to 55 foot-pounds.
N O T E : Before installation of differential case i n t o carr i e r lubricate the inside of differential assembly w i t h
Multi-Purpose H y p o i d Gear L u b r i c a n t Part N u m b e r
2933565 or equivalent. Do not use any other lubricant
other than this special lubricant.
(7) Follow procedure outlined i n conventional axle
assembly for setting drive p i n i o n depth of mesh, drive
gear backlash adjustment and bearing preload adjustment.
INSTALLING S U R E - G R I P D I F F E R E N T I A L
AND CARRIER A S S E M B L Y
(1) Using a new gasket install carrier assembly i n
axle housing. Tighten m o u n t i n g nuts to 45 footpounds.
(2) Refer to "Installation of Rear A x l e Shaft", when
installing axle shafts.
(3) Connect the rear universal j o i n t .
(4) Before l o w e r i n g the rear wheels of the vehicle
to the floor, adjust rear brakes. C A U T I O N : Both rear
wheels must be raised off the floor when adjusting
brakes.
LUBRICATION
Every six months check the fluid level i n the axle
t h r o u g h the filler p l u g hole. When checking the level,
be sure the vehicle is i n a level position on an axle or
drive on type hoist. "See L u b r i c a t i o n Section'' f o r
proper level of specific axle assembly.
I n Sure-Grip Differentials, use only t h e Multi-Purpose H y p o i d Gear L u b r i c a n t Part N u m b e r 2933565 or
equivalent. Do not use any other lubricant other than
this special lubricant.
-TIGHTENING R E F E R E N C E
3-23
SPECIFICATIONS
8-3/4" Axle
TYPE
Ring G e a r Diameter
S e m i - F l o a t i n g Hypoid
8.750
............
PINION B E A R I N G S
Type
Number U s e d . . . .
Adjustment
(Large Stem)
Pre-Load Torque ( S e a l Removed)
T a p e r e d Roller
2
Collapsible S p a c e r
20 to 30 i n c h - p o u n d s
DIFFERENTIAL BEARINGS
Type
Number U s e d ,
Adjustment
T a p e r e d Roller
2
Adjusting Nut
RING GEAR AND PINION
S e r v i c e d in
Ring G e a r Runout
Back Lash
Matched S e t s
.005" Max.
.006 to .008"
DIFFERENTIAL S I D E GEAR
With Gauge
CLEARANCE
WHEEL BEARINGS
Type
Adjustment
E n d Play
Lubrication
.001 to .012"
.
.008-.018
Automotive Multi P u r p o s e
G r e a s e N L G I grade 2
LUBRICATION
Capacity
Type
T a p e r e d Roller
Adjusting Nut
4.4 Pints (3-1/2 Pints Imp. Meas.)
Multi-Purpose G e a r Lubricant, a s defined by MIL-L-2105B (API G L - 5 ) should
be used on all rear a x l e s ; s u c h a lubricant is available under Part No.
2933565 C h r y s l e r Hypoid G e a r L u b r i c a n t or a n equivalent be u s e d .
TIGHTENING REFERENCE
8-3/4" Axle
Pounds
Foot
Inch
Differential Bearing C a p Bolts
Ring G e a r to Differential C a s e Bolts (Left Hand T h r e a d )
Drive Pinion Flange Nut
(Large S t e m )
Carrier to Axle Housing Bolt Nuts
Axle Shaft Retainer Nuts
Propeller S h a f t Bolts (Rear)
S p r i n g Clip (U Bolt) Nuts
Wheel Stud Nuts
S h o c k Absorber S t u d Nuts (Lower)
90
55
170 (Min)
45
35
15
45
65
50