brake CHEVROLET DYNASTY 1993 Owner's Guide

WARNING: WHEN REMOVING THE REAR AXLE
PIVOT BUSHING ON VEHICLES EQUIPPED WITH EI-
THER REAR COIL SPRINGS OR AIR SUSPENSION.
THE REAR AXLE MUST BE SUPPORTED BY THE
AXLE AND TRAILING ARM TO ENSURE ADEQUATE
SUPPORT OF REAR AXLE.
(3) Support the rear axle assembly at both the axle
channel and the trailing arm (Fig. 6). Then remove
lower shock absorber to rear axle mounting bolt (Fig.
6).
(4) Remove hanger bracket to frame rail bolts (Fig.
7).
(5) Lower axle assembly down enough to remove
pivot bolt and hanger bracket (Fig. 7). Right side
trailing arm shown.
PIVOT BUSHING REMOVAL FROM AXLE AS- SEMBLY
Remove bushing with Remover/Installer Spe-
cial Tool C-4212-L (Press) and 3 piece set, Spe- cial Tool 6122 (Receiver Support Bridge, Bushing
Remover/Installer and Bushing Remover). (1) Install receiver (support) bridge into base of
press C-4212-L and bushing Remover/Installer disc
onto screw. (2) Position assembly with receiver bridge support-
ing trailing arm while turning screw to begin bushing
removal. (3) After bushing has begun to move replace bushing
remover/installer (round disc) with bushing remover
(oval shaped disc). Use this assembly to finish pressing
bushing out of trailing arm (Fig. 8).
PIVOT BUSHING INSTALLATION
(1) Align the bushing with the bushing mounting
hole in the trailing arm bracket (Fig. 9). Tap bushing in
slightly to hold position. (2) Assemble bushing installer Tool onto press screw
and support bridge into press base. Position assem-
bly as shown in (Fig. 10) and press bushing into
arm to depth shown in (Fig. 9). (3) Position hanger bracket on pivot bushing, and
install through bolt, loose assemble nut (Fig. 11). Right
side trailing arm shown. (4) Position hanger to frame rail (a suitable drift will
aid in guiding hanger bracket into position). Install
and tighten screws to 75 N Im (55 ft. lbs.) torque (Fig.
12). Install lower shock absorber mounting bolt, but
do not tighten. (5) Position brake hose mounting bracket to trailing
arm, install and tighten retaining screw to 11 N Im (95
in. lbs.) torque (Fig. 13). (6) Attach park brake cable housing to hanger
bracket and cable to connector.
Fig. 8 Tools Installed To Remove Bushing
Fig. 6 Remove Pivot Bushing Hanger Bracket Bolts
Fig. 7 Remove Hanger Bracket
Ä SUSPENSION AND DRIVESHAFTS 2 - 53

(7) Lower vehicle with suspension supporting vehi-
cle weight, trailing arm at design height. Tighten
pivot bolt nut and lower shock absorber mounting
bolt to 61 N Im (45 ft. lbs.) torque.
Fig. 9 Proper Position of Pivot Bushing
Fig. 10 Tools Assembled for Bushing Installation
Fig. 11 Install Hanger Bracket to Pivot Bushing
Fig. 12 Install Hanger Bracket on Frame
Fig. 13 Brake Hose Bracket & Park Brake Cable
2 - 54 SUSPENSION AND DRIVESHAFTS Ä

PIVOT BUSHING AC AG AJ AP BODY
REMOVE FROM VEHICLE
(1) Raise vehicle (see Hoisting, Group 0). Remove
brake hose mounting bracket screw (Fig. 1). (2) Detach park brake cable at connector and from
hanger bracket (Fig. 1).
WARNING: WHEN REMOVING THE REAR AXLE
PIVOT BUSHING ON VEHICLES EQUIPPED WITH EI-
THER REAR COIL SPRINGS OR AIR SUSPENSION.
THE REAR AXLE MUST BE SUPPORTED BY THE
AXLE AND TRAILING ARM TO ENSURE ADEQUATE
SUPPORT OF REAR AXLE. (3) Support the rear axle assembly at both the axle
channel and the trailing arm with jack stands (Fig.
2). Then remove lower shock absorber to rear axle
mounting bolt (Fig. 2).
(4) Remove hanger bracket to frame rail bolts (Fig.
3). (5) Lower axle assembly down enough to remove
pivot bolt and hanger bracket (Fig. 3). Right side
trailing arm shown.
PIVOT BUSHING REMOVAL FROM AXLE AS- SEMBLY
Remove bushing with Remover/Installer Spe-
cial Tool C-4702-7 Press. And 3 piece set, Special
Tool C-4212 and C-4366-1 (Receiver Support
Bridge, Bushing Remover/Installer and Bushing
Remover). (1) Install receiver (support) cup C-4366-1 into base
of press C-4212 and Bushing Remover Cup C-4702-7
onto screw. (2) Position assembly with receiver bridge support-
ing trailing arm while turning screw to begin bushing
removal. (3) After bushing has begun to move replace bushing
remover/installer (round disc) with bushing remover
(oval shaped disc). Use this assembly to finish pressing
bushing out of trailing arm (Fig. 4).
PIVOT BUSHING INSTALLATION
(1) Align the bushing with the bushing mounting
hole in the trailing arm bracket (Fig. 5). Tap bushing in
slightly to hold it in position on trailing arm. (2) Assemble Bushing Installer Special Tool
C-4702-2 onto press screw and Support Cup Special
Fig. 1 Remove Brake Hose Mounting Bracket Screw and Park Brake Cable
Fig. 2 Remove Pivot Bushing Hanger Bracket Bolts
Fig. 3 Remove Hanger Bracket
Fig. 4 Tools Installed To Remove Bushing
Ä SUSPENSION AND DRIVESHAFTS 2 - 55

Tool C-4366-1 into press base. Position assembly as
shown in (Fig. 6) and press bushing into arm to
depth shown in (Fig. 5).
(3) Position hanger bracket on pivot bushing, and
install through bolt, loose assemble nut (Fig. 7). Right
side trailing arm shown. (4) Position hanger to frame rail (a suitable drift will
aid in guiding hanger bracket into position). Install
and tighten screws to 75 N Im (55 ft. lbs.) torque (Fig.
8). Install lower shock absorber mounting bolt, but do
not tighten. (5) Position brake hose mounting bracket to trailing
arm, install and tighten retaining screw to 11 N Im (95
in. lbs.) torque (Fig. 9). (6) Attach park brake cable housing to hanger
bracket and cable to connector. (7) Lower vehicle with suspension supporting vehi-
cle weight, trailing arm at design height. Tighten
pivot bolt nut and lower shock absorber mounting
bolt to 61 N Im (45 ft. lbs.) torque.
Fig. 7 Install Hanger Bracket to Pivot Bushing
Fig. 8 Install Hanger Bracket on Frame
Fig. 9 Brake Hose Bracket & Park Brake Cable
Fig. 5 Proper Position of Pivot Bushing
Fig. 6 Tools Assembled for Bushing Installation
2 - 56 SUSPENSION AND DRIVESHAFTS Ä

REAR AXLE ASSEMBLY
REMOVE
(1) Raise vehicle (see Hoisting, Group 0). Support
axle with jack stands and remove wheel and tire as-
sembly. (2) Separate park brake cable at connector. Detach
cable housing from hanger bracket (Fig. 1).
(3) Remove lock and separate brake tube assembly
from brake hose mounting bracket (Fig. 1). (4) Remove lower shock absorber through bolts and
track bar to axle pivot bolt. Support track bar end
with wire (Fig. 2).
(5) Lower axle until spring and isolator assemblies
can be removed. Remove spring and isolator assem-
blies (Fig. 3). (6) Support pivot bushing end of the trailing arms.
(as well as axle beam with jack stands) Remove pivot
bushing hanger bracket to frame screws. Lower and
remove axle assembly from vehicle. (7) Remove rear brake assemblies, see Group 5 for
proper procedure. (8) For pivot bushing removal and installation see
PIVOT BUSHING this group.
INSTALLATION
(1) Raise and support axle on jack stands.
(2) Attach pivot bushing hanger brackets to frame
rail (Fig. 4). Tighten screws to 61 N Im (45 ft. lbs.)
torque.
(3) Install springs and isolators (Fig. 5).
(4) Raise axle and install shock absorber and track
bar through bolts loose assemble only (Fig. 6).
(5) Install brake assembly as follows:
DRUM BRAKE ASSEMBLY
(1) Position spindle, seal, and brake support to
axle after routing park brake cable through trailing
arm opening and brake tube over arm (Figs. 1). In-
stall the 4 spindle mounting bolts finger tight. Then
torque the 4 spindle mounting bolts to 75 N Im (55 ft.
lbs.) torque. (2) Install brake drum and bearings.Fig. 1 Remove Brake Hose Mounting Bracket Screw and Park Brake Cable
Fig. 2 Remove Shock Absorber and Track Bar Bolts
Fig. 3 Remove/Install Coil Spring and Isolator Assembly
Fig. 4 Attach Hanger Brackets to Frame
Ä SUSPENSION AND DRIVESHAFTS 2 - 57

(3) Install washer and nut. Tighten nut to 27-34
N Im (240-300 in. lbs.) torque while rotating brake
drum. Then back off nut to completely release pre-
load. Finger tighten nut. (4) Position nut lock with one pair of slots in-line
with cotter pin hole. Install cotter pin. Clean and in-
stall grease cap. DISC BRAKE ASSEMBLY
(1) Position caliper support and spindle to axle. In-
stall the 4 spindle mounting bolts finger tight. Then
torque the 4 spindle mounting bolts to 75 N Im (55 ft.
lbs.) torque. (2) Install hub and bearings. (3) Install washer and nut. Tighten to 27-34 N
Im
(240-300 in. lbs.) torque while rotating hub. Then
back off nut to completely release preload. Finger
tighten nut. (4) Position nut lock with one pair of slots in-line
with cotter pin hole. Install cotter pin. Clean and in-
stall grease cap. (5) Install braking disc and adapter. Install caliper
assembly (see Rear Disc Brake) in Brakes Section,
Group 5. (6) Attach brake hose and parking brake cable to
caliper and suspension arm (Fig. 7). Install brake
hose mounting bracket to caliper support. (7) Route park brake cable through hanger bracket
and lock housing end into bracket. Install cable end
into (intermediate) connector (Fig. 7). (8) Install brake hose and fitting into bracket and
install lock. Attach brake tube assembly to hose fit-
ting and tighten to 16 N Im (140 in. lbs.) torque (Fig.
7). (9) Install wheel and tire assemblies and tighten
wheel stud nuts to 129 N Im (95 ft. lbs.) torque. Re-
move jacks and lower vehicle. (10) With suspension supporting vehicle, torque
lower shock absorber bolts to 61 N Im (45 ft. lbs.).
Then torque track bar bolt to 95 N Im (70 ft. lbs.).
(11) Bleed brake system. See BRAKES, Group 5.
Fig. 5 Install Springs and Isolators
Fig. 6 Install Shock Absorber and Track Bar Fasteners (Bolts)
Fig. 7 Reconnect Brake Tube and Park Brake Cable
2 - 58 SUSPENSION AND DRIVESHAFTS Ä

FRONT AND REAR AIR SPRINGS
The front and rear air springs are essentially pneu-
matic cylinders that replace the steel coil springs.
The air filled springs allow the vehicle suspension
height to be adjusted for all weight conditions. The air springs allow for the reduction of spring
rates to improve vehicle ride characteristics.
FRONT/REAR SPRING SOLENOIDS
The front and rear solenoids control air flow in and
out of the front and rear springs. The Air Suspension
Control Module (ASCM) opens the solenoids when
the system requires air to be added to or exhausted
from the air springs. The solenoids operate at a cur-
rent draw range of 0.6 to 1.5 amps.
HEIGHT SENSOR
A magnetic switch type sensor. Located in the
right rear shock absorber and left and right front
struts, (Fig. 2) monitors vehicle height. The sensors
transmit signals to the (ASCM) relating to vehicle
height status (low, trim, medium, high).
CONTROL MODULE
The Air Suspension Control Module (ASCM). Is a
device that controls the ground circuits for the Com-
pressor Relay, Compressor Exhaust Solenoid Valve
and Front and Rear Solenoid Valves. The (ASCM)
limits the compressor pump operation time to 170 to
190 seconds. This controlled operation time is to pre- vent damage to the compressor motor.
To prevent excessive cycling between the compres-
sor and the exhaust solenoid circuits during normal
ride conditions. A 14 to 16 second delay is incorpo-
rated in the microprocessor logic. The system is non-operation when one of the fol-
lowing conditions exists. A door(s) is/are open, the
trunk is open, the service brake is applied or the
throttle position sensor is 65% to 100% open. System
operation is inhibited during high speed cornering
activities or if there is a charging system failure.
The control module is on the CCD bus system.
COMPRESSOR ASSEMBLY
The compressor assembly is driven by an electric
motor and supplies air pressure between 930 to 1241
kPa (135 to 180 psi) (Fig. 3). A solenoid operated ex-
haust valve. Located in the compressor head assem-
bly, releases air when energized. A heat actuated circuit breaker. Located inside the
compressor motor housing. Is used to prevent damage
to the compressor motor in case of control module
failure.
COMPRESSOR AIR DRYER
The air dryer is attached to the compressor (Fig. 3).
This component serves two purposes. It absorbs mois-
ture from the atmosphere before it enters the system
Fig. 2 Front and Rear Air Springs
2 - 74 SUSPENSION AND DRIVESHAFTS Ä

and with internal valving maintains a residual pres-
sure of 172 to 276 kPa (25 to 40 psi).
AIR LINES
Nylon air lines (4) are routed from the compressor
(air dryer) to each strut/spring assembly. Rightside
strut and air spring air lines are routed with the fuel
lines. Leftside strut and air spring air lines are
routed across the vehicle (forward of the fuel tank).
And to the front of the vehicle with the brake lines
(Figs. 4 and 5).
Fig. 3 Air Compressor/Dryer Assembly
Fig. 4 Air Lines Front
Ä SUSPENSION AND DRIVESHAFTS 2 - 75

(3) Check solenoid to volume canister joint.
² Front strut to solenoid valve connection.
² Rear spring to solenoid valve connection.
(4) Check air line for ruptures, cuts, splits or heat
damage. Use a soap and water solution or a liquid de-
veloped for leak detection.
SYSTEM OPERATION
ENGINE RUN OPERATION
The system will compensate for load
addition/removal when.
² The trunk and all doors are closed.
² The engine speed exceeds 600 R.P.M.
² Throttle angle is less than 65 degrees.
² The brake is not applied.
² You are not cornering above 10 mph.
² There is not a charging system problem with the
vehicle.
ENGINE OFF OPERATION
After passengers/load is removed from the vehicle
the system will correct the vehicle attitude after:
² The trunk and all doors are closed.
² The ignition switch is in the OFF position.
Opening the a door or trunk wakes up the body
computer and the air suspension module. The air
suspension system is now capable of leveling, if
required.
LONG TERM IGNITION OFF OPERATION
The system is capable of one an additional leveling
cycle. After 2 continuous hours of ignition key off and
no door open or trunk open activities. This feature is
implemented to eliminate possible ice freeze-up be-
tween the tire and the inner fender shield.
SYSTEM OPERATION INHIBITORS
The air suspension system is inhibited when:
² The trunk is open.
² A door(s) is/are open.
² The brake pedal is engaged.
² The throttle is at the wide open position.
² The charging system fails.
The maximum compressor pump or exhaust
time is 3 minutes.
SYSTEM FAILURES
Vehicles equipped with air suspension and overhead
console. Will alert the driver of an air suspension
system malfunction. A warning Check Air Suspension
will appear on the overhead console screen.
SAFETY CONCERNS
WARNING: REAR AIR SPRINGS MUST BE DEFLATED
BEFORE BEING REMOVED FROM THE VEHICLE.
WARNING: OPEN TRUNK, OR DOOR(S) OR REMOVE
GROUND STRAP FROM BATTERY BEFORE HOIST-
ING OR JACKING A VEHICLE DURING MECHANICAL
REPAIRS.
WARNING: IF THE VEHICLE NEEDS SERVICE OR
REPAIR OF THE REAR SHOCK ABSORBERS OR
REAR AXLE PIVOT BUSHINGS. THE REAR AIR
SPRINGS MUST HAVE THE AIR PRESSURE RE-
MOVED BEFORE THE VEHICLE CAN BE SERVICED
SAFELY.
SHIPPING MODE
(1) Removing shipping height signal for customer
use.
² Use DRB II tester and 1991 Chassis (Air Suspen-
sion) service cartridge.
² Follow DRB II requirements to cancel shipping
height message in the body computer.
² Connect the Ignition Off Draw (I.O.D.) circuit.
The connection of the IOD circuit will cancel
the Shipping height signal. (2) Return to shipping height.
² Set shipping command in the body computer using
the DRB II and the 1991 Chassis (Air suspension)
service cartridge.
² Disconnect the I.O.D. connector.
DIAGNOSIS
INITIAL DIAGNOSTIC CHECK
(1) Check for blown or missing fuses.
Fig. 9 Compressor Current Draw Test
2 - 78 SUSPENSION AND DRIVESHAFTS Ä

REAR (STUB) AXLE ALIGNMENT ALL MODELS INDEX
page page
General Information ....................... 89 Rear Wheel Alignment..................... 89
GENERAL INFORMATION
Because front wheel drive vehicles are equipped with
rear suspension incorporating stub axles (or wheel
spindles). It is possible to align both the camber and toe
of the rear wheels.
REAR WHEEL ALIGNMENT
Alignment adjustment if required. Is made by adding
0.010 inch shims (from the service package kit) be-
tween the spindle mounting surface and axle mounting
plate. Each shim equals wheel change by .3É as shown
(for all car lines) in (Figs. 3 to 6). If rear wheel alignment is required, place vehicle on
alignment rack and check alignment specifications.
When recording rear toe-in (vehicle backed onto
alignment rack) REMEMBER to reverse sign
convention; a total toe-in on direct reading
charts is actually toe-out while driving. Maintain
rear alignment within Chrysler Motors recommenda-
tions, found in Specifications.
INSTALLATION OF REAR ALIGNMENT SHIMS
(1) Block front tires so vehicle will not move.
(2) Release parking brake.
(3) Hoist vehicle so that rear suspension is in full
rebound and tires are off the ground. See Hoisting in
Lubrication and Maintenance, Group 0. (4) Remove wheel and tire assembly.
(5) Pry off grease cap.
(6) Remove cotter pin and castle lock.
(7) Remove adjusting nut.
(8) Remove brake drum (Fig. 1). (9) Loosen four (4) brake assembly and spindle
mounting bolts enough to allow clearance for shim
installation (Fig. 2). Do not remove mounting
bolts.
(10) Install shims as shown in Figs. 3, 4, 5 and 6
for desired wheel change. No more than two shims
on each spindle should be used to bring alignment
within acceptable range. Wheel change by .3É per shim.
(11) Tighten down the 4 brake support plate and
spindle to axle mounting bolts until they are snug.
Then tighten the 4 bolts to the torque values listed
for the vehicle line which is being serviced.
² AA, AG, AJ, AP Bodies 75 N Im (55 ft. lbs.)
Fig. 2 Loosen Mounting Bolts
Fig. 3 Shim Installation for Toe-Out
Fig. 1 Remove Brake Drum
Ä SUSPENSION AND DRIVESHAFTS 2 - 89