HEATER AND AIR CONDITIONING 1A-65
Fig.
92—Chevrolet Four-Season Ducts
Installation
Reverse
assembly.
the removal procedure to reinstall the duct
Left Outlet Duct
Removal
1.
Remove the two parking brake lever bracket to
dash brace attaching screws and move the lever and
cable so they will not interfere with the duct
removal.
2.
Remove the screw and lock washer attaching the duct
outer bracket to the hinge pillar support.
3.
Remove the screws and lock washers attaching the
duct assembly to the dash brace bracket.
4.
Carefully pull the outer end of the duct downward,
detaching the courtesy light from its bracket.
5. Loosen the screws clamping the outlet duct to dis-
tributor assembly flexible tubing at the outlet duct.
The outlet duct may now be removed from beneath
the instrument panel.
6. The duct extension assembly and the deflector as-
sembly may be removed, if desired, as seen in
Figure 95.
Installation
The duct assembly is installed by reversing the re-
moval instructions.
Center Outlet Duct
Removal
1.
Remove the right and left console trim panels.
2.
Remove the radio receiver.
3.
Remove the electric clock.
4.
Remove the knobs, nuts and bezels from the two
air conditioning controls above the clock, AIR COND.
PULL and COLD IN-HOT PULL.
5. Carefully pull the outlet duct and control cables
loose from the rear of the center console and work
it down and out from under the dash. The left hand
control cable runs through the left hand flexible
tubing and may be left in the tubing after it is dis-
engaged from the duct. The right hand control cable
must also be pulled from the duct assembly as the
duct is removed.
6. The center deflector barrel assembly may now be
removed if necessary. Snap off the hairpin clips to
remove the barrel and spacer washers.
Installation
Reverse the removal procedure for installation.
AIR DISTRIBUTOR ASSEMBLY
Removal
1.
Drain the cooling system radiator.
2.
Remove the heater hoses from the core pipes and
remove the cover attaching nuts and cover surround-
ing the core pipes.
3.
Remove the glove compartment assembly and the
glove compartment door.
NOTE:.
See "Section 1 - Body" for removal
and installation of body items.
4.
Remove the right kick pad.
5. Remove the right and left center console trim panels.
6. Remove the radio receiver assembly.
7. Remove the defroster duct.
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-6
Fig.
10—Toe-in Adjusting Shim Location (Corvette)
Toe-in
Wheel toe-in is adjusted by inserting shims of varying
thickness inside the frame side member on both sides
of the torque arm pivot bushing (fig. 10). Shims are
available in thicknesses of
1/64",
1/32",
1/8" and 1/4".
To adjust toe-in, remove torque arm pivot bolt; then
position torque arm to obtain specified toe-in. Shim gap
toward vehicle centerline between torque arm bushing
and frame side inner wall.
NOTE: Do not use thicker shim than necessary,
and do not use undue force when shimming inner
side of torque arm - to do so may cause toe
setting to change.
Shim outboard gap as necessary to obtain solid stack-
up between torque arm bushing and inner wall of frame
side member. After correct shim stack has been se-
lected, install pivot bolt and hardened washers (fig. 10) -
making sure that all shims are retained - torque nut to
specifications and install cotter pin. If specified torque
does not permit cotter pin insertion, tighten nut to next
flat.
WHEEL BEARING ADJUSTMENT (CORVETTE)
inspection
The tapered-roller spindle bearings should have end
play of .001" to
.008".
During inspection, check end
play and, when necessary, adjust as outlined in this
section.
1.
Raise rear of vehicle until wheels clear ground.
2.
Disengage bolt lock tabs and disconnect outboard end
of axle drive shaft from wheel spindle flange.
3.
Mark camber cam in relation to bracket. Loosen and
turn camber bolt until strut rod forces control arm
outward. Position loose end of axle drive shaft to
one side for access to spindle.
4.
Remove wheel and tire assembly. Mount dial in-
dicator (Tool J-8001) on torque arm or adjacent
surface and rest pointer on flange or spindle end
(fig. H).
5.
Grasp brake disc and move axially (in and out) while
reading movement on dial indicator. If end movement
is within the .001" to .008" limit, bearings do not
require adjustment. If not within .001" to .008"
limit, record reading for future reference and adjust
bearings as outlined below.
Adjustment
1.
Apply parking brake to prevent spindle from turning
and remove cotter pin and nut from spindle.
2.
Release parking brake and remove drive spindle
flange from splined end of spindle.
3.
Remove brake caliper and brake disc as outlined in
Section 5.
4.
Install Thread Protector J-21859-2 over spindle
threads; then remove drive spindle from spindle
support, using Tool J-22602 as shown in Figure 12.
CAUTION: When using Tool J-22601 to remove
drive spindle, make sure puller plate is posi-
Fig.
11—Checking Wheel Bearing Adjustment (Corvette)
Fig. 12—Removing Drive Spindle from Support (Corvette)
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-9
Fig.
17—Rear Spring—Exploded View (Chevy II)
LEAF SPRING, SPRING SEAT PADS, SPRING EYE
BUSHINGS Chevy II (Fig. 17)
Removal
1.
Raise vehicle and support rear axle assembly.
2.
Pull parking brake cable out of lower spring pad
mounting bracket clamp and disconnect cable above
axle housing. Remove four nuts securing lower
spring pad mounting bracket to axle spring seat
(fig. 18). Drop lower bracket and remove rubber
spring pad.
3.
Loosen and drive out front spring eye bolt. Lower
spring and remove front rubber eye bushing (fig. 19).
4.
Remove nuts from rear spring shackle (fig. 20),
spread shackle to separate it from spring eye and
support bracket and remove spring. Remove rear
spring eye bushings.
5.
Remove upper spring pad cushion.
Installation
1.
Inspect spring eye bushings and spring pads for ex-
cessive wear or aging and replace as necessary.
Inspect spring rear shackles, front spring bracket
and eye bolt for bending or cracking and correct
where needed.
2.
Assemble spring rear shackle as follows:
a. All except Station Wagons (fig. 21).
Fig.
19—Removing Front Eye Bushings (Chevy II)
3.
' Fig. 20—Disassembling Rear Spring Shackle (Chevy II)
1.
Insert inboard rubber spring eye bushings into
i'ear spring eye and outboard shackle bushings
into shackle mounting bracket.
2.
Position spring and install shackle to spring
and mounting bracket with top nut toward out-
board of vehicle and bottom nut toward vehicle
centerline.
3.
Tighten nuts but-do not torque at this point,
b.
Station Wagon (fig. 22):
When installing shackle as in Step 2 above, top
nut should be toward centerline of vehicle and
bottom nut toward outboard of vehicle.
Insert inboard rubber bushing into front spring eye.
Fig.
18—Removing Lower Pad Bracket (Chevy II)
Fig.
21—Rear Spring Shackle Exploded View-All
Except Station Wagon (Chevy II)
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-11
lower cushion
correct.
will be aligned if installation is
Fig.
25—Installing Spring Front Bushing (Camaro)
Unnecessary torque applied after flange is
seated will tend to distort flange and reposition
bushing in spring.
i. Disassemble bushing installation tools and re-
move from spring.
8. Pry parking brake cable out of the retainer bracket
mounted on the spring mounting plate.
9. Remove spring bracket-to-axle bracket retaining
nuts,
remove upper and lower rubber spring pads
and bracket.
10.
Support spring, then remove lower bolt from spring
rear shackle. Separate shackle and withdraw spring
from vehicle.
11.
Remove rear spring shackle upper bolt and withdraw
shackle bushings from frame.
Installation
1.
Position spring front mounting bracket to spring
front eye. Spring attaching bolt must be installed
so that head of bolt is toward center of vehicle.
2.
Position spring shackle upper bushings in frame,
position shackles to bushings and loosely install
bolt and nut.
3.
Install bushing halves in spring rear eye, place
spring to shackles and loosely install shackle lower
bolt and nut.
NOTE: When installing spring, make sure
spring is positioned so that parking brake cable
is on underside of spring.
4.
Raise front end of spring and position bracket to
underbody. Guide spring into position so that it will
index in the axle bracket and also make sure that
the tab on spring bracket is indexed in slot pro-
vided in the underbody.
5.
Loosely install spring-to-underbody bracket.
6. Position spring upper cushion between spring and
axle bracket so that spring cushion ribs align with
axle bracket locating ribs.
7.
Place lower spring cushion on spring so that .cushion
is indexed on locating dowel. Upper cushion and
8. Place lower mounting plate over locating dowel on
spring lower pad and loosely install retaining nuts.
9. If new mounting plate was installed, transfer parking
brake cable retaining bracket to new plate.
10.
Position shock absorber to spring mounting plate and
loosely install eye bolt and nut - head of bolt should
be toward front of vehicle.
11.
Position parking brake cable in retaining bracket and
securely clamp bracket to retain cable.
12.
Remove stand jacks and lower vehicle so that weight
of vehicle rests on suspension components. Torque
all affected parts to specifications.
SHOCK ABSORBER
Chevrolet and Chevelle
Removal
1.
Raise rear of vehicle and support rear axle
assembly.
If equipped with superlift shock absorber, disconnect
air line from shock absorber.
Disconnect shock absorber at upper mounting bracket
by removing the two retaining bolts. Refer to Figure
26 for shock absorber mounting details. (Chevelle
components shown as typical.)
Disconnect shock absorber at lower attaching bracket
and remove shock.
NOTE: When performing any service opera-
tions that requires removal or loosening of the
lower attaching nut, it is essential that the stud
be prevented from turning. A hex is located on
the stud between the axle bracket and shock
absorber in order that a wrench may be used
for this purpose. Failure to hold the stud in
this manner will result in damage to the mer
chanical bond between the shock absorber bush-
ing and the mounting stud.
2.
3.
STATION WAGON AND PICKUP
Fig.
26—Shock Absorber Mounting—Exploded View
(Chevelle)
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-18
ig.
44—Rear Suspension Tie Rod Attaching Points (Chevrolet)
Bushing
Replacement
The following bushing removal procedure is effective
for both ends of the tie rod used on station wagons and
the left end of the tie rod used on all models except
station wagons.
1,
With tie rod bushing centered over Tool J-7877-2
and with tie rod supported horizontally, press or
drive bushing from rod, using Tools J-7877-1 and
J-7079-2 as shown in Figure 45.
2.
With tie rod centered over Tool J-7877-2 and rod
supported horizontally, press or drive bushing into
arm using Tools J-7877-3 and J-7079-2 as shown
in Figure 45. Tool J-7877-3 should bottom on tie
rod when bushing is fully installed.
fig.
45—Tie Rod Bushing Replacement (Chevrolet)
Installation
1.
Mount the tie rod to the axle bracket stud. Install
nut and special washer but do not tighten.
NOTE:
On the tie rod used on all models except
station wagons, place flanged portion of bushing
against attaching bracket.
2.
Install the bolt, lock washer and nut to the frame
bracket (fig. 44). Do not tighten.
NOTE:
Bolt may be installed from either
direction.
3.
Lower vehicle to floor (if raised) and bounce rear
end several times to settle bushings. Tighten af-
fected parts to specifications.
COMPONENT PARTS REPLACEMENT (CORVETTE)
WHEEL SPINDLE AND SUPPORT (Fig. 46)
Removal
Hemdve wheel drive spindle as outlined previously in
this section under "Wheel Bearing Adjustment".
Repairs
Out of 3/8" square steel bar stock, make bearing
removers and use as shown in Figure 47.
After removing deflector, spindle inner grease seal
and inner bearing race, bearing cups may be re-
moved while spindle support is still mounted to the
torque arm, by inserting remover tool and tapping
cup out. New bearing cups are installed using Tool
J-7817 cup installer and handle J-8092 (fig. 48).
To remove spindle support from torque arm, pro-
ceed as follows.
a. Disconnect parking brake cable from actuating
lever.
b.
Remove four nuts securing support to torque arm
and withdraw brake backing plate and position it
out of the way.
c. Disconnect shock absorber lower eye from strut
rod mounting shaft. It may be necessary to sup-
port spring outer end before disconnecting shock
absorber, as shock absorber has internal rebound
control.
d. Remove cotter pin and nut from strut rod mount-
ing shaft, then pull shaft from support and strut
rod.
e. Spindle support may then be removed and bearing
cups serviced as in Step 2 above.
4.
To remove drive spindle outer bearing and seal
proceed as follows.
a. Position Tool J-8331 between chamfered edge of
bearing seat and inner race of bearing (fig. 49).
Clamp Tool J-8331 in a vise and apply pressure
to unseat bearing.
CAUTION: Use extreme caution when position-
ing Tool J-8331 against machined surface of
spindle. Make sure all tool imperfections such
as nicks and burrs are removed from spindle
contact area before applying pressure to unseat
bearing.
b.
Position Tool J-8331 and spindle in an arbor
press and press bearing from spindle (fig. 50).
c. Remove outer seal and inspect for damage--re-
place if necessary. Outer seal must be placed on
spindle before outer bearing inner race and roller
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-20
Fig.
51—Shock Absorber Installation (Corvette)
6. Tap new spindle inner grease seal into seal bore
and install deflector over support inner end.
Installation
1.
Position support over torque arm bolts with strut
rod fork toward center of vehicle and downward.
Place backing plate over studs and torque nuts to
specifications.
2.
Connect parking brake cable to actuating lever.
3.
Install drive spindle assembly as outlined previously
in this section under "Wheel Bearing Adjustment".
4.
If new spindle support or associated parts are in-
stalled, determine correct shim size as follows.
a. Assemble spindle to support, using a .145" shim.
b.
Check bearing adjustment and correct as neces-
sary, following adjustment procedures previously
outlined.
DIFFERENTIAL CARRIER SUPPORT
BRACKET REPLACEMENT
1.
Place a 1/2" thick block of wood or steel between
nose of differential carrier and floor pan. This will
prevent carrier from twisting upward when support
bracket is disconnected.
2.
Remove carrier support-to-crossmember attaching
bolt.
3.
Remove nut from both of the bracket-to-carrier
through bolts.
4.
Slide bolts to one side until bolt head contacts floor
well. Mark the floor well at this point and drill a
3/4"
diameter hole for each bolt in floor well and
remove bolts.
5. Assemble carrier support bracket by reversing
above procedure. Torque all affected parts to
specifications.
6. Insert plastic plugs from the inside of the floor well
holes to prevent dust and water entry.
STRUT ROD SHAFT STRUT ROD
CAMBER CAM
AND BOLT
Fig.
52—Strut Rods (Corvette)
SHOCK ABSORBER (Fig. 51)
Removal
1.
Disconnect shock absorber upper mounting bolt*
2.
Remove lower mounting nut and lock washer.
3.
Slide shock upper eye out of frame bracket and pull
lower eye and rubber grommets off strut rod mount-
ing shaft.
4.
Inspect grommets and shock absorber upper eye for
excessive wear.
Installation
1.
Slide upper mounting eye into frame mounting
bracket and install bolt, lock washer and nut.
2.
Place rubber grommet, shock lower eye, inboard
grommet, washers and nut over strut rod shaft.
3.
Torque nuts to specifications.
STRUT ROD AND BRACKET (Fig. 52)
Removal
1.
Raise vehicle enough to provide working clearance.
2.
Disconnect shock absorber lower eye from strut
rod shaft.
3.
Remove strut rod shaft cotter pin and nut. With-
draw shaft by pulling toward front of vehicle (fig. 53).
4.
Mark relative position of camber adjusting cam and
Fig.
53-Removing Strut Rod Shaft (Corvette)
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-23
Fig.
62—Torque Control Arm (Corvette)
2.
Place center clamp plate in position and install four
bolts and washers. Tighten bolts and torque to
specifications.
3.
Raise spring outer end with floor jack until spring
is nearly flat and secure with chain as in Step 3-
Removal.
.4.
Lower jack, align torque control arm with spring
end and insert link bolt, rubber cushions and re-
tainers. Install castellated nut on link bolt and
tighten until cotter pin hole in bolt is visible. In-
sert new cotter pin and bend ends around.
5. Raise spring end with jack under link bolt, and re-
move chain and C clamp when loose.
6. Carefully lower jack, making sure rubber cushions
remain indexed in retainers.
7. Remove jack and repeat on opposite side. Install
wheels and tires, remove frame supports and lower
vehicle to floor.
TORQUE CONTROL ARM (Fig. 62)
Removal
1.
Disconnect spring on side torque arm is to be re-
moved. Follow Steps 1-6, Spring-Removal.
NOTE:
If vehicle is so equipped, disconnect
stabilizer rod from torque arm - refer to
"Stabilizer Rod Replacement".
2.
Remove shock absorber lower eye from strut rod
shaft.
3.
Disconnect and remove strut rod shaft and swing
strut rod down.
4.
Remove four bolts securing axle drive shaft to
spindle flange and disconnect drive shaft.
NOTE:
It may be necessary to force torque
arm outboard to provide clearance to drop drive
shaft.
5. Disconnect brake line at wheel cylinder inlet or
caliper and from torque arm. Disconnect parking
brake cable.
6. Remove torque arm pivot bolt and toe-in shims and
pull torque arm out of frame. Tape shims together
and identify for correct reinstallation.
RETAINER
RETAINER
PLATE
BUSHING
CONTROL ARM
Fig.
63—Torque Control Arm Bushing Cross-Sect ion (Corvette)
NOTE:
For service operations pertaining to
the spindle support assembly, refer to service
operations under Wheel Spindle and Support
earlier in this section.
Repairs (Fig. 63)
1.
Using 11/16" drill, drill out flared end of bushing
retainer (fig. 64).
2.
Remove special retainer plate and tap retainer out
of bushing.
3.
Remove bushings by spreading them apart with a
chisel and tap out of arm (fig. 65).
NOTE:
If bushing diameters are severely
rusted in torque arm, and arm tends to spread
during removal, clamp arm in a C-clamp to
prevent spreading.
Fig.
64—Drilling Out Retainer Flare (Corvette)
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