
REAR SUSPENSION AND DRIVE LINE 4-27
SHIM AND
SERVICE
12
14
Fig.
72—Rear Axle Cross-Section (Chevrolet, Camaro, Chevelle and Chevy II)
1.
Companion Flange
2.
Deflector
3. Pinion Oil Seal
4.
Pinion Front Bearing
5. Pinion Bearing Spacer
6. Differential Carrier
LUBRICANT
7. Differential Case
8. Shim
9. Gasket
10.
Differential Bearing
11.
"Clock
12. Pinion Shaft Lock Bolt
13.
Cover
14.
Pinion Shaft
15.
Ring Gear
16.
Side Gear
17.
Bearing Cap
18.
Axle Shaft
19.
Thrust Washer
20.
Differential Pinion
21.
Shim
22.
Pinion Rear Bearing
23.
Drive Pinion
MAINTENANCE AND ADJUSTMENTS
The lubricant level should be periodically checked and
maintained at level of filler plug with a warm axle. See
the lubrication section of this manual for lubricant
recommendations.
Lubricant Leaks
Lubricant leaks should be checked for at the pinion
flange oil seal, axle wheel bearing seals, lubricant-filler
plug, and carrier cover. Correction of these leaks con-
sists of replacing the defective seals or gaskets involved
as described in this section.
AXLE BOLTS AND WHEEL NUTS
From a safety standpoint, axle housing to rear spring
bolts,
wheel nuts and control arm attaching bolts should
be periodically inspected for secure installation.
CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-30
Fig.
76—Differential Gear Failure
Hypoid Gears
Hypoid gear tooth scoring (fig. 74) is caused generally
by improper break-in, incorrect lube, insufficient gear
backlash or improper 'ring/pinion gear alignment. The
scoring will progressively lead to complete erosion of
the gear tooth, or gear tooth pitting and eventual fracture
with possible attendant damage to bearings, if the initial
scoring condition is not diagnosed in time and corrected.
Hypoid gear scoring is easily recognized by its char-
acteristic loud whine in either drive, coast or under both
conditions. Another cause of hypoid tooth fracture (fig.
75) is extended overloading of the gear set which will
produce fatigue fracture, or shock loading which will
result in sudden failure.
Differential Gears
Common causes of differential gear failure are shock
loading, extended overloading leading to fatigue failure,
and overheating of gear thrust surfaces resulting from
excessive wheel spin and consequent lubrication break-
down. Overheating will lead to seizing of thrust surfaces
or tooth failure (fig. 76).
Bearings
• Failure of axle tapered roller bearings is due pri-
marily to excessive wear caused by long service or
foreign materials in the oil. The second most common
cause of bearing failure is too tight or too loose pre-
load adjustment leading to spalling and eventual failure.
This failure may also lead to hypoid gear scoring due to
the resultant misalignment of the hypoid gear set.
COMPONENT PARTS REPLACEMENT
(Chevrolet, Cheveile, Chevy II and Camaro)
AXLE ASSEMBLY
Removal
1.
Raise vehicle to a height that will permit axle as-
sembly to hang freely and position supports under
both frame side rails.
2.
Disconnect wheel cylinder inlet lines. Disconnect and
remove brake hose and brake line retaining bracket
by removing retaining bolt from carrier cover.
3.
Loosen parking brake equalizer adjusting nut and
disconnect both rear cables at frame bracket and at
control arms. See Section 5 for detail of parking
brake cable removal.
4.
Remove two trunnion bearing "U" bolts from the
rear yoke and separate rear universal joint. Wire
propeller shaft to frame side rail and tape trunnion
bearing cups.
5. Support arid secure axle assembly with an adjustable
lifting device. On Chevrolet and Cheveile models,
loosen upper and lower control arm attaching bolts
at axle housing. (On Chevrolet models, disconnect
tie rod at axle bracket.)
6. Disconnect shock absorbers at axle brackets. Refer
to Shock Absorber Removal procedures outlined in
this section.
7. On Chevrolet and Cheveile models, lower axle as-
sembly until suspension reaches end of travel, then
disconnect spring retainers and withdraw springs
from vehicle.
8. On Chevy II and Camaro models, remove four nuts
securing lower spring seat to axle housing, then
remove spring front eye bolts or spring attaching
bracket and swing spring to rear so that it does not
interfere with axle.
9. On Chevrolet and Cheveile models, disconnect upper
and lower control arm attaching bolts at axle housing*
10.
Lower axle assembly and remove from under vehicle.
Installation
1.
Place axle assembly under vehicle and raise into
position.
2.
On Chevrolet and Cheveile models, install, but do not
tighten, upper and lower control arm attaching bolts
at axle housing.
3.
On Chevrolet models, position coil springs in upper
seats so that end of spring is indexed in seat.
4.
On Chevrolet models, install lower end of spring on
axle bracket or control arm and secure by installing
retainer and bolt. Install lock washer and retainer
nut.
5. On Cheveile pry lower pigtail of spring over vertical
flange of the axle bracket spring seat.
6. On Chevy II and Camaro models, install spring seat
pads and swing springs up into spring seats on axle
housing, making sure upper seat pads are aligned in
axle housing bracket.
7. Install spring front eye bolt and tighten, then install
spring seat lower mounting bracket and retaining
nuts.
8. Raise axle assembly to allow shock absorber and tie
rod installation. Position shock absorber in axle
bracket. Torque nut as outlined in Shock Absorber
Installation procedures.
9. Install brake hose and brake line retaining bracket
to carrier and connect wheel cylinder inlet lines.
Connect parking brake cable to frame bracket and
at control arm. Adjust parking brake and bleed
brakes as outlined in Section 5.
10.
Reassemble rear universal joint to companion flange.
11.
Support vehicle at axle and remove supports from
beneath the frame side rails.
12.
Remove supports and lower vehicle to floor. Torque
all affected parts to specifications.
CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-31
Fig.
77—Differential Pinion Shaft Removal
AXLE SHAFT
Removal
1.
Raise vehicle to desired working height and remove
wheel and tire assembly and brake drum.
2.
Clean all dirt from area of carrier cover. *
3.
Drain lubricant from carrier by removing cover.
4.
Remove the differential pinion shaft lock screw and
the differential pinion shaft (fig. 77).
5. Push flanged end of axle shaft toward center of
vehicle and remove "C" lock from button end of
shaft.
6. Remove axle shaft from housing, being careful not
to damage oil seal.
Wheel Bolt Replacement .
Press bolts out of axle shaft flange (as illustrated in
Figure 78) and press new bolts into place, making sure
that they are tight and square with flange.
Off Seal and/or Bearing Replacement
•1.
Remove the oil seal by using the button end of the
axle shaft - insert the button end of the shaft behind
the steel case of the oil seal, then pry seal out of
bore being careful not to damage housing.
2.
Insert Tool J-8119 into bore and position it behind
bearing so that tangs on tool engage bearing outer
x race. Remove bearing, using slide hammer as shown
in Figure 79. Figure 80 shows a detail of axle
housing outer end.
3.
Lubricate new bearing with wheel bearing lubricant,
and install bearing so that it bottoms against
Fig.
79—Wheel Bearing Removal
shoulder (fig. 81). To install bearing use Tool
J-21491 for the Chevelle, Camaro and Chevy JI
light-duty axle and Tool J-21051 for all Chevrolet
models and also for Chevelle, Camaro and Chevy tl
models with heavy-duty axle.
Pack cavity between the seal lips with a high melting
point wheel bearing lubricant; position seal on tool
(Use J-21491 for the Chevelle, Camaro and Chevy II
light-duty axle and J-21051 for all Chevrolet models
and also for Chevelle, Camaro and Chevy II models
with heavy-duty axle) and position seal in axle
housing bore, tap seal into place so that it bottoms
against bearing (fig. 81).
Brake Flange Plate Replacement
1.
Remove "brake line at wheel cylinder inlet and dis-
assemble brake components from flange plate. Refer
to Section 5 for brake disassembly procedure.
2.
Remove 4 nuts securing flange plate to axle housing.
3.
Install new flange plate to axle housing and torque
nuts to specifications.
Fig.
78—Wheel Bolt Replacement
Fig.
80-Axle Housing Detail
CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-34
COMPONENT PARTS REPLACEMENT (CORVETTE)
AXLE DRIVESHAFT-FIGURE 88
Removal
1.
Disconnect inboard driveshaft trunnion from side
gear yoke.
2.
Bend bolt lock tabs down and remove four bolts
securing shaft flange to spindle drive flange.
3.
Pry driveshaft out of outboard drive flange pilot
and remove by withdrawing outboard end first (fig.
89).
Repairs
1.
Remove bearing lock ring from trunnion yoke.
2.
Support turnnion yoke on a piece of 1-1/4" pipe on
arbor press bed.
3.
Using suitable socket or rod, press trunnion down
far enough to drive opposite bearing cup from yoke.
4.
Remove trunnion and press other bearing cup from
yoke, being careful not to
drop'
cup
or lose bearing
rollers.
5. Remove trunnion and yoke from other joint in a
similar manner.
3
AXLE
II 1
i
c
DRI\
c
y
'E SHAFT ^
AXLE
v
DRIVE^
SHAFT
•
Fig.
88—Axle Driveshaft
6. Remove dust seals from trunnion, clean and inspect
bearing rollers and trunnion. Relubricate bearings
with a high-melting point wheel bearing type
lubricant.
NOTE:
In addition to packing the bearings,
make sure that the lubricant reservoir at the
end of each trunnion is completely filled with
lubricant. In filling these reservoirs, pack lu-
bricant into the hole so as to fill from the .
bottom. This will prevent air pockets and en-
sure an adequate supply of lubricant.
7. Place new dust seals on trunnion, cavity of seal
toward end of trunnion - then position Tool J-21556
over end of trunnion and into cavity portion of seal.
Press seal onto trunnion until tool bottoms against
trunnion (fig. 90).
NOTE:
Installation of seal is critical to proper
sealing - use specified tool during installation
to prevent seal distortion and to assure proper
seating of seal on trunnion.
8. Partially install one bearing cup into yoke. Place
trunnion in yoke and into bearing cup. Install other
bearing cup and press both bearing cups into yoke,
being careful to keep trunnion aligned in bearing
cups.
9. Press bearing cups far enough to install lock rings,
and install lock rings.
NOTE:
It may be more convenient, if neces-
sary, to use a bench vise for removal and
installation, instead of an arbor press. In this
case, proceed with disassembly and assembly
procedure as with an arbor press.
Installation
1.
Place driveshaft inboard trunnion into side gear
yokes and assemble
"XJ"
bolts. Rotate yokes so that
trunnion seats are phased 90° apart.
2.
Install outboard drive flange into spindle drive flange
pilot, position bolt lock over bolt holes and install
four bolts. Torque bolts to specification and bend
lock tabs flat against bolt heads.
Fig. 89—Removing Driveshaft
Fig.
90—
"U"
Joint Trunnion Seal Installation
CHEVROLET CHASSIS SERVICE MANUAL

REAR SUSPENSION AND DRIVE LINE 4-36
Fig.
94—Installing Pinion Oil Seal
DIFFERENTIAL CARRIER
Removal
1.
Disconnect spring end link bolts as outlined in
Spring—Removal, in this section.
2.
Disconnect axle drive shafts at carrier by removing
"U"
bolts securing trunnion to side gear yoke.
3.
Disconnect carrier front support bracket at frame
crossmember.
4.
Disconnect propeller shaft at transmission and at
companion flange. Slide transmission yoke forward
into transmission. Drop propeller shaft down and
Fig.
95-Pinion Sea! Installed
out toward the rear.
5. Mark camber cam and bolt relative location on strut
rod bracket and loosen cam bolts.
6. Remove four bolts securing bracket to carrier lower
surface and drop bracket. Remove camber cam bolts
and swing strut rods up and out of the way.
7. Remove eight carrier-to-cover bolts. Loosen bolts
gradually to allow lubricant to drain out.
8. With mounting bolts removed, pull carrier partially
out of cover, drop nose to clear crossmember and
gradually work carrier down and out.
Installation
1.
Clean inside of carrier cover and liberally grease
gasket surface. Place new gasket on cover.
2.
Cut heads off two l/2"-13 x 1-1/4" bolts and slot
unthreaded end. Install these aligning studs into two
below-center carrier bolt holes, one on each side.
3.
Raise carrier into position aligning studs into
cover (fig. 96).
4.
Install carrier-to-cover bolts and tighten securely.
5. Connect propeller shaft to companion flange and
transmission yoke.
6. Install rubber cushion on bracket and position to
frame crossmember. Install hut and torque to
specifications.
7. Raise axle drive shafts into position and assemble
inboard trunnion to side gear yokes with "U" bolts.
8. Assemble strut rods to bracket and raise bracket
into position under carrier. Install four bolts and
torque to specifications. Move camber cams to
marked location and tighten cam nuts.
Fig.
96—Installing Carrier Assembly
CHEVROLET CHASSIS SERVICE MANUAL

BRAKES 5-5
LEVEL CYLINDER
TILTED CYLINDER
Fig.
8—Correct Main Cylinder Fluid Level
expelled brake fluid flows in a solid stream from the
bleeder hose and no bubbles are present, then close
bleeder valve tightly.
6. Remove brake bleeder wrench and bleeder hose from
wheel cylinder bleeder valve.
7. Repeat Steps 2 through 7 on the remaining wheel
cylinders in the correct bleeding sequence (fig. 5).
8. Fill the main cylinder to the levels shown in
Figure 8.
9. Install main cylinder diaphragm and cover.
PUSH ROD TO MAIN CYLINDER CLEARANCE
The brake pedal has a definite stop which is permanent
and not adjustable. This stop consists of a rubber
bumper at the release end of pedal travel. Before
adjusting push rod to main cylinder clearance, make
sure pedal returns to the fully released position freely
and that the pedal retracting spring has hot lost its
tension, then proceed as follows:
1.
Loosen check nut on push rod.
2.
Turn push rod as required to provide correct ad-
justment. Movement of pedal pad before push rod
contacts main cylinder pistons must be 1/16" to
1/4" (fig. 9).
3.
Tighten check nut against clevis, and recheck
movement.
HYDRAULIC BRAKE LINES
Hydraulic Brake Hose
The flexible hoses which carry the hydraulic pressure
from the steel lines to the wheel cylinders are carefully
designed and constructed to withstand all conditions of
stress and twist which they encounter during normal
vehicle usage.
The hoses require no service other than periodic
inspection for damage from road hazards or other like
sources. Should damage occur and replacement become
necessary, the following procedure is to be followed.
Removal
1.
Separate hose from steel line by turning double
flare connector out of hose fitting.
2.
Remove "U" shaped retainer from hose fitting and
withdraw hose from support bracket.
3.
Turn hose fitting out of wheel cylinder inlet.
Replacement
1.
Install new copper gasket on cylinder end of hose
(male end).
2.
Moisten threads with brake fluid and install hose in
wheel cylinder inlet.
3.
With weight of car on wheels and suspension in
normal position (front wheels straight ahead) pass
female end of hose through support bracket, allowing
hose to seek its own position. Insert hex of hose
fitting into the 12 point hole in support bracket
in position which induces least twist to hose (figk 10).
NOTE:
Do not twist hose unduly during ^
operation as its natural curvature is absolutely
necessary to maintain proper hose-tot
suspension clearance through full movement o£
the suspension and steering parts.
4.
Install "U" shaped retainer to secure hose in sup-
port bracket.
5. Inspect by removing weight completely from wheel,
turn wheels from lock to lock while observing hose
position. Be sure that hose does not tough other
parts at any time during suspension or wheel travel.
If contact does occur, remove hose retainer and
rotate the female hose end in the support bracket
CHEVROLET CHASSIS SERVICE MANUAL

BRAKES 5-6
Fig.
9—Brake Pedal Free Movement
one or two points in appropriate direction, replace
retainer, and re-inspect.
6. Place steel tube connector in hose fitting and tighten
securely.
7. Bleed all brakes as outlined in this section.
8. Do not tighten male end (wheel cylinder end) once
the other end is fixed. If necessary to tighten male
1 end, disconnect hose at opposite end, then reconnect
following above procedure.
Hydraulic Brake Tubing
Hydraulic brake tubing is a double layer annealed
steel terne plate tubing which resists corrosion and has
the physical strength to stand up under the high pr.es-
Fig.
11—Hydraulic Brake Tube Double Flaring Tool
sures which are developed when applying the brakes. In
making up hydraulic brake pipes, it is important that
the proper flaring tool be used to flare the ends of the
tubing for the compression couplings. Unless the tubing
is properly flared, the connections will leak and the
brakes will become ineffective.
CAUTION: When necessary to replace brake
tubing, always use special steel tubing which
is designed to withstand high pressure and re-
sist corrosion. Ordinary copper tubing is not
satisfactory and should not be used.
This safety steel tubing must be double-lap flared at
the ends in order to produce a strong leak-proof joint.
The brake tube flaring. Tool J-8051 (fig. 11) is used to
form the double-lap flare.
Figure 12 shows two pieces of tubing, one with single-
lap flare "A" and the other with double-lap flare "B".
It will be noted that the single-lap flare in "A" split
the tubing while the one shown in "B" is well-formed and
unbroken due to the reinforcement of the double wall.
The following procedure should be followed in making
up hydraulic brake pipes.
Double Lap Flaring
1.
Clamp the tubing in the proper size die blocks with
the flat ends of the blocks toward the end of the
tubing to be cut off. Cut the end of the tubing flush
and square. Using a mill file, dress tubing and
square ends.
Fig.
10-Brake Line Support Bracket
Fig.
12—Single and Double Lap Flaring
CHEVROLET CHASSIS SERVICE MANUAL

BRAKES 5-7
LATCH PLATE
DIE BLOCK
TUBE
UPSET FLARE PUNCH
RAM GUIDE
STOP PLATE
Fig.
13—Flaring Operation--Position ing Tubing
2.
Remove the tubing from the die block and deburr
the inside and outside edges.
3.
Install compression couplings on tubing and dip end
of tubing to be flared in hydraulic fluid. This lubri-
cation results in better formation of the flare.
4.
Place on-half of the die blocks in the tool body with
the counterbored ends toward the ram guide. Now
lay the tubing in the block with approximately 1/2"
protruding beyond the end.
Fit the other half of the block into the tool body,
close the latch plate and tighten the nuts "finger
tight".
5. Select the correct size upset flare punch. One end
of this punch is counterbored or hollowed out to
gauge the amount of tubing necessary to form a
double lap flare. Slip the punch into the tool body
with the gauge end toward the die blocks. Install the
ram; then tap lightly until the punch meets the die
, blocks and they are forced securely against the
stop plate (fig. 13).
6. Using the supplied wrench, draw the latch plate
nut down tight to prevent the tube from slipping.
Tightening the nuts alternately (beginning with the
nut at the closed hole in the plate) will prevent
distortion of the plate. Remove the punch and the
ram. Now reverse the punch and put it back into the
tool body. Install the ram and tap it lightly until
the face of the upset flare punch contacts the face
of the die blocks (fig. 14). This completes the
first operation. Remove the ram and the punch.
7. To complete the flare, insert the pointed finish
flare punch and the ram into the tool body. Tap
the ram until a good seat is formed (fig. 15).
NOTE:
The seat should be inspected at inter-
vals during the finishing operation to avoid
over-seating.
LATCH
DIE BLOCK
TUBE
UPSET FLARE PUNCH
RAM GUIDE
RAM
1ST OPERATION
UPSET FLARE
PUNCH
2ND OPERATION
FINISH FLARE
PUNCH
Fig.
15—Flaring Operation—First and Second Flare
BRAKE ADJUSTMENT
Service Brake
Although the brakes are self-adjusting, a preliminary
or initial adjustment may be necessary after the brakes
have been relined or replaced, or whenever the length
of the adjusting screw has been changed. The final
adjustment is made by using the self-adjusting feature.
1.
With brake drum off, disengage the actuator from
the star wheel and rotate the star wheel by spinning
or turning with a small screw driver.
2.
Recommended
a. Use special Tool J-21177; Drum-to-Brake Shoe
Clearance Gauge, to check the diameter of the
brake drum inner surface (fig. 16).
Fig.
14—Flaring Operation—First Flare
Fig.
16—Using Drum-to-Brake Shoe Clearance
Gauge Tool J-21177
CHEVROLET CHASSIS SERVICE MANUAL