FRONT SUSPENSION 3-9
Inspection
1.
Check bearings for cracked separators or worn or
pitted rollers and races.
2.
Check brake drum for
out-of-
round or scoring.
3.
Check fit of bearing outer cups in hub.
Repairs
Replacement of Bearing Cups
1.
Using steel bar stock, make press-out tools shown in
Figure 11.
2.
Insert removers through hub, indexing ends into slots
in hub shoulder behind bearing cup.
3.
Using a suitable extension pipe or rod, press bearing
cups from hub.
4.
Install new bearing cup in hub using Tool J-8849 on
the outer and Tool J-8850 on the inner cup (fig. 12).
Use Driver Handle J-8092 with the installers. Make
sure that the bearing cups are not cocked and are
fully seated against shoulder in hub.
Installation
1.
Pack both inner and. outer bearings using a high
melting point wheel bearing lubricant.
2.
Place inner bearing in hub, then install a new inner
bearing lip seal assembly. Seal flange should face
bearing cup.
3.
Carefully install wheel hub over steering spindle.
4.
Install outer bearing, pressing it firmly into the hub
by hand.
5.
Install spindle washer and adjusting nut. Draw up
tight and adjust wheel bearings as outlined under
"Front Wheel Bearing Adjustment".
STEERING KNUCKLE
Chevrolet, Chevelle, Camaro and Corvette—It is rec-
ommended that vehicle be raised and supported on a
twin-post hoist so that the front coil spring remains com-
pressed, yet the wheel and steering knuckle assembly re-
main accessible. If a frame hoist is used, support lower
control arm with an adjustable jackstand to safely retain
spring in its curb height position.
Chevy n— While vehicle weight is still on front wheels,
position support between upper control arm and frame
side rail (fig. 13), then raise vehicle and position adjust-
able jackstand under lower control arm.
Removal
1.
Raise vehicle and support lower control arm as noted
above.
2.
Remove hub cap, wheel hub dust cover, cotter pin,
adjusting nut and washer. Withdraw wheel and tire,
brake drum, (or, on Corvette--brake caliper and disc
and hub assembly, See Section 5) and wheel hub and
bearing assembly from steering knuckle spindle.
3.
Remove brake shoes from backing plate (except
Corvette, See Section 5) and clamp wheel cylinder.
CAUTION: Keep brake shoes clean and dry.
4.
Remove brake anchor pin and two bolts securing
brake backing plate and steering arm to steering
knuckle.
5.
Withdraw steering arm and brake backing plate from
steering knuckle. Wire backing plate to frame (fig.
13).
Do not disconnect brake line.
NOTE: Refer to Section 9 - Steering Linkage -
Tie Rod, for further steering arm service
operations.
6. Remove upper and lower ball stud cotter pins and re-
move ball stud nuts. Free steering knuckle from
ball studs by rapping steering knuckle bosses. With-
draw steering knuckle.
Installation
1.
Place steering knuckle in position and insert upper
and lower ball studs into knuckle bosses.
2.
Install ball stud nuts and tighten nut as shown in the
specifications at the end of this section.
Fig.
12 - Installing Front Hub Inner Bearing
Fig.
13 - Backing Plate Removed - Chevy II
CHEVROLET CHASSIS SERVICE MANUAL
FRONT SUSPENSION 3-12
2.
Remove forward nut, retainer and rubber bushing
from front end of strut rod.
3.
Remove two nuts from strut rod to lower control arm
bolts and remove bolts and washers.
4.
Withdraw strut rod from bracket.
5. Remove remaining rubber bushing, retainer, sleeve
and nut from strut rod.
6. Inspect rubber bushings for aging and replace if
necessary. *•
Installation
1.
Screw rear nu$ on forward end of rod and position it
approximately 3/4" from end of threads. Install
rear retainer, sleeve and bushing on rod so raised
pilot diameter faces forward.
2.
Insert strut rod in bracket so pilot diameter on bush-
ing pilots in hole in bracket. Install forward bushing
on sleeve so raised pilot diameter faces rear to
enter hole in bracket, then install forward retainer
and nut on rod.
3.
Attach strut rod to top of lower control arm with two
bolts,
washers and nuts.
4.
Lower vehicle to floor, check caster and camber
angles and adjust where necessary. Torque nuts as
shown in Specifications.
FRONT SPRING
Chevrolet
Removal
1.
With an open end wrench hold the shock absorber
upper stem from turning, and then remove the upper
stem retaining nut, retainer and rubber grommet.
I IVi" rVi"i
\>. j ii
>
I
5'4
s
WOOD
BLOCK
USED
WITH
CHEVROLET
ONLY
Fig.
19
- Spring Removal Tools - Chevrolet, Chevelle and Comoro
2.
With the car supported by the frame so that the con-
trol arms hang free, remove the wheel and tire as-
sembly (replace one wheel nut to retain the brake
drum),
shock absorber, stabilizer bar to lower con-
trol arm link, strut rod to lower control arm attach-
ing, nuts, bolts and lock washers and tie rod end.
3.
Scribe the position of the inner pivot camber adjust-
ing cam bolt and then remove the nut, lock washer
and outer cam.
4.
Install a steel bar (fabricated as shown in Figure 19)
through the shock abosrber mounting hole in the
lower control arm so that the notch seats over the
bottom spring coil and the bar extends inboard and
under the inner bushing. Fit a 5" wood block (See
Figure 19) between the bar and the bushing as shown
in Figure 20.
5.
With suitable jack or hoist, lift up slightly on the end
of the bar to remove the tension from the inner pivot
cam bolt, which can then be removed.
Fig.
18-Strut Rod
Pig. 20 - Front Spring Removal - Chevrolet
CHEVROLET CHASSIS SERVICE MANUAL
FRONT SUSPENSION ,3-13
6. Carefully lower the inner end of the control arm.
Tension on the spring will be removed before the
spring can be removed from the vehicle.
7.
Remove the spring.
Installation
1.
With the suspension set up as in Step 2 of the disas-
sembly procedure, insert a block of wood between the
upper control arm and the spring tower to keep the
arm up out of the way.
2.
Set the spring in place on the crossmember after
checking on proper positioning necessary.
3.
Install the steel bar and wood block as shown in Fig-
ure 20 and lift the control arm up until the inner
pivot cam bolt can be installed. ,
4.
Install the outer cam and loosely install the lock
washer and nut
5.
Set the cam bolt on the mark scribed during the re-
moval procedure and hold in this position while tight-
ening the nut (See specifications at the end of this
book).
6. Replace the strut rod to lower control arm nuts,
bolts and lock washers, the stabilizer bar link, the
shock absorber, the tie rod end, and the wheel and
tire.
7.
Lower vehicle to floor and install the shock absorber
upper stem retaining nut retainer and grommet.
8. Check the camber adjustment.
Chevelle and Camaro
Removal
1.
With an open end wrench hold the shock absorber up-
per stem from turning, and then, remove the upper
stem retaining nut, retainer and rubber grommet.
2.
With the car supported by the frame so that the con-
trol arms hang free, remove the wheel and tire as-
sembly (replace one wheel nut to retain the brake
drum),
shock absorber, and stabilizer bar to lower
control arm link.
4.
5.
Fig.
21 - Front Spring Removal - Chevelle & Camaro
Place a steel bar (fabricated as shown in Figure 19)
through the shock absorber mounting hole in the
lower control arm so that the notch seats over the
bottom spring coil and the bar extends outboard be-
yond the end of the control arm and slightly toward
the front of the car.
With a suitable jack or hoist lift up slightly on the
end of the bar.
Remove the lower ball stud cotter pin and attaching
nut and remove the ball stud from the knuckle.
ALTERNATE METHOD
Fig.
22 - Removing or Installing Front Coil Spring - Corvette (Typical)
CHEVROLET CHASSIS SERVICE MANUAL
FRONT SUSPENSION 3-16
available the following procedure may also be
used (fig. 22-Alternate Method).
1.
Support car on suitable hoist or jack (so control
arms may swing free) and remove the wheel and
tire assembly, shock absorber, and stabilizer link
at control arm.
2.
Place suitable jack stand under the lower control
arm cross shaft.
3.
Follow Steps 2-5 as outlined on previous page.
4.
Turn head of tool screw to partially compress
spring.
5. Remove the three control arm cross shaft attaching
bolts,
washers and nuts.
6. Carefully lower jack stand and if necessary increase
compression on spring and when coil spring is out of
its upper seat, relax tension on spring (fig. 22).
7. By using a pry bar to assist, if necessary, remove
the coil spring from the lower control arm.
8. Installation is the reverse of the above procedure.
Carefully follow instructions for installing spring
tool.
LOWER CONTROL ARM SPHERICAL JOINT
Chevrolet, Chevelle, Comoro and Corvette
Inspection
The lower control arm spherical joint should be re-
placed whenever wear is indicated in the upper joint
inspection.
NOTE: The lower control arm spherical joint
is a loose fit in the assembly when not connected
to the steering knuckle.
Only if inspection of each upper joint indicates them
both to be within limits, inspect each lower joint for ex-
cessive wear as follows:
1.
After reconnecting upper joints to steering knuckles,
support vehicle weight on wheels or wheel hubs.
2.
With outside micrometer or caliper, measure dis-
tance from top of lubrication fitting to bottom of ball
stud, and record the dimensions for each side.
3.
Then support vehicle weight at outer end of each
lower control arm, so that wheels or wheel hubs are
free,
then repeat Step 2.
4.
If the difference in dimensions on either side is
greater than 1/16" (.0625"), the joint is excessively
worn and both lower joints should be replaced.
If inspection of lower spherical joints does not indicate
excessive wear, inspect further as follows:
5.
On Chevrolet Only--Examine lubrication hole in each
joint assembly after cleaning out hole. Look for evi-
dence of the liner partially or fully blocking lubrica-
tion opening. Such evidence indicates that liner is
disintegrating and that both lower spherical joints
should be replaced.
Another indication of lower spherical joint excessive
wear is indicated when difficulty is experienced when
lubricating the joint. If the liner has worn to the point
where the lubrication grooves in the liner have worn
away, then abnormal pressure is required to force lubri-
cant through the joint. This is another reason to recom-
mend replacement of both lower joints.
If the above inspections do not indicate any reason for
spherical joint replacements, test the torque tightness of
Fig. 27 - Removing Lower Ball Joint - Chevelle
&
Camaro
the lower ball stud in the knuckle on each side as follows:
1.
Wire-brush off nut and cotter pin attaching spherical
joint ball stud to steering knuckle and examine for
evidence of looseness of stud in knuckle.
2.
If no evidence of looseness, remove cotter pin and
with prick punch or equivalent, mark nut stud and
knuckle to identify relative location.
3.
Tighten nut as installed and observe torque reading.
If less than 45 lbs. ft., stud may have been loose in
steering knuckle and replacement of both lower
spherical joints may be recommended.
4.
Check to see if torque of 60-94 lbs. ft. can be ob-
tained without bottoming stud or ball joint against
knuckle. If bottoming occurs, replace ball joint or
steering knuckle.
Chevrolet and Corvette
Removal
1.
Support lower control arm at outer end on floor jack,
with hoist or jack pad clear of lower ball stud nut.
2.
Remove upper and lower ball stud nuts, free ball
studs from steering knuckle and wire knuckle and
brake drum assembly up to fender skirt to preclude
interference while performing next step.
3.
Being careful not to enlarge the holes in control arm,
cut off rivets.
Installation
1.
Install new joint against underside of control arm and
CHEVROLET CHASSIS SERVICE MANUAL
SECTION
4
REAR SUSPENSION
AND
DRIVE LINE
CONTENTS
OF
THIS SECTION
Page
Rear Suspension
4-1
Drive Line.
. 4-26
Rear Axle ......
4-26
Propeller Shaft
and
Universal Joints
Special Tools
4-37
4-43
REAR SUSPENSION
INDEX
General Description
4-1
Chevrolet
4-1
Chevelle
4-1
Chevy
n and
Camaro
. . . . . 4-2
Corvette
. . . . . . 4-3
Maintenance
and
Adjustments ...............
4-4
Riding Height Check (Chevrolet, Camaro,
Chevelle
and
Chevy
II) 4-5
Wheel Alignment (Corvette)
4-5
Wheel Bearing Adjustment (Corvette)
4-6
Component Parts Replacement (Chevrolet, Camaro,
Chevelle
and
Chevy
JJ) 4-7
Coil Spring
4-7
Chevrolet
4-7
Removal
4-7
Installation
4-7
Chevelle
4-8
Removal
4-8
4-8
Installation
.
Leaf Spring, Spring Seat Pads, Spring
Eye
Bushings
4-9
Chevy
H 4-9
Removal
4-9
Installation
4-9
Camaro
4-10
Removal
4-10
Installation
4-11
Shock Absorber
4-11
Chevrolet
and
Chevelle
. 4-11
Removal
4-11
Installation
. . 4-12
Chevy
II 4-12
Removal
4-12
Installation
4-rl2
Camaro
4-12
Removal
. 4-12
Installation
4-12
Control
Arm . . 4-12
Chevrolet Upper
4-12
Removal
. 4-12
Page
Bushing Replacement
. 4-13
Installation
4-14
Chevrolet Lower
4-14
Removal
4-14
Bushing Replacement
4-14
Installation
. 4-15
Chevelle Upper
and
Lower.
. 4-15
Removal
4-15
Bushing Replacement
4-15
Installation
4-17
Rear Suspension
Tie Rod
(Chevrolet)
. . .
......
. . . 4-17
Removal
4-17
Bushing Replacement
4-17
Installation
4-17
Component Parts Replacement (Corvette)
. . 4-17
Wheel Spindle
and
Support
4-17
Removal
4-17
Repairs
', . 4-17
Installation
4-18
Differential Carrier Support Bracket Replacement.
. 4-20
Shock Absorber
4-20
Removal
4-20
Installation
* .... 4-20
Strut
Rod and
Bracket
4-20
Removal
4-20
Repairs
4-21
Installation
4-21
Spring
4-21
Removal
4-21
Repairs
4-22
Installation
4-22
Torque Control
Arm 4-23
Removal
4-23
Repairs
. 4-23
Installation
4-24
Suspension Crossmember
4-24
Removal
4-24
Repairs—Isolation Mount
4-25
Installation
4-25
Stabilizer Shaft Replacement
4-25
GENERAL DESCRIPTION
CHEVROLET
The link type rear suspension (fig. 1) has two lower
control arms which maintain proper axle to frame re-
lationship and also take the acceleration, drive and
braking forces. A single upper control arm on light-
duty models (or two upper control arms on heavy-duty
models and all station wagons) limits axle rotation when
drive, acceleration or braking forces are applied. Lateral
movement of the axle is restricted by the axle-to-frame
tie rod. Two full coil springs and two direct, double
acting shock absorbers are provided for additional ride
control.
CHEVELLE
The rear suspension (fig. 2) is of the four-link design
utilizing axle mounted, full coil springs and direct,
double-acting shock absorbers.
Two rubber-bushed lower control arms, stretching
slightly outboard from axle-mounted brackets to frame
side member mounted brackets, maintain fore and aft
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-8
Fig.
14—Coil Spring Installation (Chevrolet)
supported on the jack. With the spring now com-
pressed to approximately curb height, positively
position the springs in the lower seats by torquing
the nut on the lower seat bolt (fig. 15).
Re-connect shock absorbers, torque rear attach-
ment of upper and lower control arms, and re-
connect the axle tie rod at proper torque.
With the rear of vehicle still supported by jack under
axle;
remove the nut from the lower seat bolt of one
Fig.
15—Installing Coil Spring to Lower Control Arm (Chevrolet)
Fig.
16—Coil Spring Installation (Chevelle)
rear spring, slide proper lock washer on the bolt
and reinstall the nut to proper torque. Similarly
install a lock washer at the lower seat of the other
rear spring.
5.
Install rear wheels and lower vehicle to floor.
Chevelle
Removal
The following procedure may be utilized to replace
either or both rear coil springs.
1.
Raise vehicle to a height that will allow axle assem-
bly to hang freely, and position supports under both
frame side rails.
2.
Support axle assembly with an adjustable lifting
device, and disconnect shock absorber at axle
bracket. Shock absorber on side opposite need not
be disconnected if only one spring is being removed.
Refer to Shock Absorber Removal procedures out-
lined in this section.
3.
Lower axle assembly until suspension reaches end
of travel; then pry lower% pigtail over vertical re-
tainer on axle bracket and remove spring and insula-
tor from vehicle.
Installation
1.
Position rubber insulator on end of spring, making
sure that end of pigtail is butted against stop in
insulator. Install insulator and spring in upper
spring seat so that insulator is properly indexed
against stop (fig. 16).
2.
Pry lower pigtail portion of spring over vertical
flange of the axle bracket spring seat.
3.
Raise axle to allow shock absorber installation.
Position shock absorber in axle bracket. Torque nut
as outlined in Shock Absorber Installation
procedures.
4.
Lower vehicle and check rear riding height.
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION AND DRIVE LINE 4-15
ship of parts, then install Spacer J-
7574-
3 over
the partially installed bushing and between the
sides of the control arm.
f. Continue to tighten J-
21058-
8
until bushing is
pulled flush against control arm. Do not exert
undue force against control arm after bushing is
installed. Overtightening of J-21058-
8
will cause
damage to walls of control arm.
g. Disassemble tools and inspect bushing for proper
installation.
Replace the rear bushing as follows:
a. Position Puller Screw J-21058-8 through Re-
mover Adapter J-21830-2 so that head of screw
is opposite button end of remover. Install this
assembly, threaded end of sc'rew first, through
bushing to be removed.
b.
Install Receiver J-21830-4 and Bridge J-21830-7
. over screw and against control arm. Position
thrust bearing against J-21830-7 and screw
J-21058-8 snugly against bearing. Install Spacer
J-
2183d-
3
between sides of control arm and over
bushing.
c. Check tool installation for proper alignment and
tighten J-21058-8 to withdraw bushing from con-
trol arm. Refer to Figure 35 for installed view
of tools.
d. Disassemble tools and position Installer Adapter
J-21830-2 on flanged end of new bushing. Posi-
tion bushing in control arm making sure of cor-
rect installation. Small end of bushing will pass
through one side of arm without any interference.
e. Install J-21830-4, J-21830-7, thrust bearing and
J-21058-8 on threaded end of J-21058-15 as
shown in Figure 36. Tighten J-21058 to main-
tain proper relationship of parts; then position
Spacer J- 21830- 3 over bushing and between sides
of control arm.
f. Tighten J-21058-8 until bushing is fully seated
J-21058-8 J-21830-7 J-21830-4 J-21830-3 J-21830-2
\
J-2K
X
D58-8
J-218
30-7
IP
•he?
21830-4
J-21830-2
JfSir
J-21830-3
Fig.
35—Lower Control Arm Rear Bushing Removal
(Chevrolet)
Fig.
36—Lower Control Arm Rear Bushing Installation
(Chevrolet)
against side of control arm. Do not apply undue
pressure to J-21058 after bushing is seated--to
do so may cause permanent distortion to control
arm.
g. Disassemble tools and check bushing for proper
installation.
Installation
NOTE:
Make sure control arm is reinstalled
in proper forward attaching position. Reinstall
in same hole as noted during removal. Top
attaching hole is used for all installations except
station wagons and heavy-duty suspension (RPO
F41).
Opposite arm must be installed in cor-
responding position.
1.
Position the control arm between the mounting
brackets and loosely install the pivot bolt retaining
nuts in the proper position.
2.
Install spring and shock absorber as outlined in this
section.
3.
Lower vehicle so that weight is placed on sus-
pension components and torque all affected parts to
specifications.
Chevelle Upper and Lower
Removal
NOTE:
If both upper control arms and both
lower control arms are to be removed at the
same time, remove both coil springs as outlined
under "Coil Spring Removal".
1.
Raise vehicle to a height that will allow axle assem-
bly to hand freely and position supports under both
frame side rails.
2.
Support axle assembly with an adjustable lifting de-
vice and raise rear axle assembly until tension is
relieved in control arm being removed.
3.
Disconnect control arm at forward and rearward
attaching points and remove from vehicle.
Bushing Replacement
The upper arm front bushing and carrier ear bushings
are of the same part number and are interchangeable.
CHEVROLET CHASSIS SERVICE MANUAL
REAR SUSPENSION
AND
DRIVE LINE
4-26
DRIVE LINE
REAR AXIE
INDEX
Page
General
Description
4-26
Chevrolet,
Camaro,
Chevelle
and
Chevy
II 4-26
Corvette
4-26
Maintenance
and
Adjustments
4-27
Lubricant
4.37
Lubricant'
Leaks
4_27
Axle Bolts
and
Wheel
Nuts
4-27
Rear Axle Noise
Diagnosis
4-29
Gear Noise
4_29
Bearing
Noise
4-29
Failure
Analysis
4^9
Hypoid
Gears
4..3Q
Differential Gears. 4_30
Bearings
....'.
4.30
Component Parts Replacement
(Chevrolet, Chevelle, Camaro and Chevy n ..... 4.30
Axle Assembly ,. . 4_30
Removal 4 30
Installation * ' 4 3Q
Axle Shaft . . . 4-31
Removal 4-31
Wheel Bolt Replacement 4-31
Oil Seal and/or Bearing Replacement. 4-31
Brake Flange Plate Replacement 4-31
Installation 4-32
Pinion Flange, Dust Deflector and/or
Oil Seal Replacement 4-32
Component Parts Replacement (Corvette) 4-34
Axle Driveshaft .- 4-34
Removal 4-34
Repairs 4-34
Installation. . 4-34
Pinion Flange, Dust Deflector and/or Oil Seal. .... 4-35
Removal 4-35
Inspection . 4-35
Installation .- 4-35
Differential Carrier 4-36
Removal 4-36
Installation 4-36
Positraction Differential Unit-On the Vehicle Check . . 4-37
\
GENERAL DESCRIPTION
CHEVROLET, CHEVELLE, CHEVY
I! AND
CAMARO
The rear axle
(fig. 72) is a
semifloating, fabricated
construction type consisting
of a
cast carrier with large
bosses
on
each
end
into which
two
welded steel tubes
are fitted.
The
carrier contains
an
overhung hypoid
pinion
and
ring gear.
The
differential
is a
two pinion
arrangement.
The axle housing
is
made up
of
two steel welded tubes
pressed into
the
crossbore
of the
cast carrier
-
each
tube
is
puddle welded
at
three places
to the
carrier.
Welded-on brackets provide attachment points
for
Chevelle springs,; shock absorbers,
and
lower control
arms.
Chevrolet models have welded-on brackets
for
control arms,
tie
rod, and shock absorbers. The housing
on Chevy II and Camaro has welded brackets
for
mounting
lower spring
pad
and shock absorber.
A
welded flange
is
provided
for
brake flange plate attachment.
The overhung hypoid drive pinion
is
supported
by
two
preloaded tapered roller bearings.
The
pinion shaft
is
sealed
by
means
of a
molded, spring loaded, rubber seal.
The seal
is
mounted
on the
pinion shaft flange which
is
splined and bolted
to
the hypoid pinion shaft.
The hypoid ring gear
is
bolted
to a
one-piece differen-
tial case which
is
supported
by two
preloaded tapered
roller bearings.
CORVETTE
The Corvette rear axle
is of the
type where
the dif-
ferential carrier housing enclosing
the
differential
and
hypoid gears
is
supported
on a
crossmember mounted
to
the chassis frame.
The
differential
is
connected through
universal joints
to the
drive shafts
and
wheels
(fig. 73).
The internal components
of the
carrier
are of
conven-
tional design, incorporating
a
hypoid gear
set
with
an
overhung pinion supported
on two
pre-loaded, tapered
roller bearing assemblies,
and a
two-pinion differential
assembly supported
on
tapered roller bearings. Pinion
mounting distance adjustments
are
made through the
use
of shims,
as are the
differential bearing pre-load
and
backlash adjustments.
The
differential side gears drive
two splined yokes which
are
retained laterally
by
snap
rings located on the yoke splined end. The yokes
are
sup-
ported on caged needle bearings pressed into
the
carrier,
adjacent
to the
differential bearings.
A
lip seal, pressed
in outboard
of
the bearings, prevents
oil
leakage and dirt
entry.
The
carrier cover
is
bolted
to the
carrier and
provides accessibility
to the
internal parts.
The
cover
incorporates two integral, reinforced mounting pads which
serve
as the
carrier attaching point
to the
suspension
crossmember,
and an
attaching point
for the
spring
center section. The filler plug
is
located on the right side
of the cover near the bolting flange.
All service operations allow carrier removal without
removing
the
carrier cover. Cover removal
is
not nec-
essary
in any of the
service procedures except
in
the
case
of
complete carrier housing replacement,
as the
carrier and cover
are
serviced
as
an assembly.
CHEVROLET CHASSIS SERVICE MANUAL