wheel CHRYSLER VOYAGER 2001 Service Manual

(20) Road test vehicle. The automatic adjuster will
continue the brake adjustment during the road test
of the vehicle.
ADJUSTMENT - REAR DRUM BRAKE SHOES
NOTE: Normally, self-adjusting drum brakes do not
require manual brake shoe adjustment. Although, in
the event of a brake shoe replacement, it is advis-
able to make the initial adjustment manually to
speed up the adjusting time.
NOTE: Before raising the vehicle, verify the parking
brake lever is fully released.
(1) Raise the vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(2) Remove rubber plug from rear brake adjusting
hole in the rear brake support plate.
(3) Insert a thin screwdriver through the adjusting
hole in the support plate and against the star wheel
of the adjusting screw. Move handle of the tool
upward rotating the star wheel until a slight drag is
felt when tire and wheel assembly is rotated.
(4) Insert a second thin screwdriver or piece of
welding rod into brake adjusting hole and push the
adjusting lever out of engagement with the star
wheel.Care should be taken so as not to bend
adjusting lever or distort lever spring.
(5) While holding the adjusting lever out of
engagement, back off the star wheel just enough to
ensure a free wheel with no brake shoe drag.
(6) Repeat the above adjustment at the other rear
wheel.
(7) Install the adjusting hole rubber plugs back in
the rear brake support plates.
(8) Lower the vehicle.
DISC BRAKE CALIPERS -
FRONT
REMOVAL - FRONT DISC BRAKE CALIPER
(DISC/DISC BRAKES)
(1) Depress the brake pedal past its first inch of
travel and hold it in this position using a brake pedal
depressor (holding) tool. This is done to isolate the
master cylinder from the brake hydraulic system dis-
allowing the brake fluid to completely drain out of
the brake fluid reservoir.
(2) Raise the vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(3) Remove front wheel and tire assembly.(4) Remove the banjo bolt connecting the brake
hose to the brake caliper. There are two washers (one
on each side of the brake hose fitting) that will come
off with the banjo bolt. Discard these washers.
(5) Remove the 2 caliper guide pin bolts.
(6) Remove the brake caliper from the adapter.
REMOVAL - FRONT DISC BRAKE CALIPER
(DISC/DRUM BRAKES)
(1) Using a brake pedal holding tool, depress the
brake pedal past its first one inch of travel and hold
it in this position. This will isolate the master cylin-
der from the brake hydraulic system and will not
allow the brake fluid to drain out of the master cyl-
inder reservoir when the lines are opened.
(2) Raise the vehicle. Refer to HOISTING in
LUBRICATION AND MAINTENANCE.
(3) Remove the front tire and wheel assembly.
(4) Remove the banjo bolt connecting the brake
hose to the brake caliper (Fig. 32). There are two
washers (one on each side of the flex hose fitting)
that will come off with the banjo bolt. Discard the
washers.
(5) Remove the two brake caliper guide pin bolts
(Fig. 32).
(6) Remove the disc brake caliper from the disc
brake adapter.
Fig. 32 Brake Caliper Mounting (Typical)
1 - BRAKE HOSE
2 - ADAPTER MOUNTING BOLTS
3 - BANJO BOLT
4 - CALIPER GUIDE PIN BOLTS
5 - 22 BRAKES - BASERS
BRAKE PADS/SHOES - REAR DRUM (Continued)

(7) Reinstall the caliper on the vehicle and bleed
the brakes as necessary. Refer to Installation in this
section.
INSTALLATION - FRONT DISC BRAKE CALIPER
(DISC/DISC BRAKES)
CAUTION: TRW and Continental Teves brake cali-
pers are not interchangeable. Each caliper is specif-
ically designed for the unique brake system (TRW -
disc/drum brake combination and Continental Teves
- disc/disc brake combination). If calipers are inter-
changed, improper performance, noise and
increased stopping distance can occur.
(1) Completely retract the caliper piston back into
piston bore of the caliper. Use a C-clamp to retract
the piston if necessary. Place a wood block over the
piston before installing the C-clamp to avoid damag-
ing the piston.
CAUTION: Use care when installing the brake cali-
per assembly onto the steering knuckle, so that the
seals on the caliper guide pin bushings do not get
damaged by the steering knuckle bosses.
(2) Carefully position the brake caliper and shoes
over the brake rotor and adapter.
(3) Install the caliper guide pin bolts and tighten
to a torque of 35 N´m (26 ft. lbs.).Extreme caution
should be taken not to cross thread the caliper
guide pin bolts.
(4) Install the anti-rattle clip on the outboard side
of the caliper. Start the clip into the holes on the cal-
iper, then stretch the clip legs past the abutments on
the caliper adapter.
CAUTION: When connecting the brake hose to the
caliper, install new brake hose to caliper special
copper washers.
(5) Install the brake hose on the caliper. To do
this, first place one NEW special fitting washer on
each side of the hose fitting, then slide the banjo bolt
through the fitting. Next, thread the banjo bolt into
the threaded port on the rear of the brake caliper.
Tighten the banjo bolt to a torque of 47 N´m (35 ft.
lbs.).
(6) Install the wheel and tire assembly. Tighten
the wheel mounting stud nuts in proper sequence
until all nuts are torqued to half specification, then
repeat the tightening sequence to the full specified
torque of 135 N´m (100 ft. lbs.).
(7) Lower the vehicle.
(8) Remove the brake pedal depressor (holding)
tool.
(9) Bleed the hydraulic brake circuit to the brake
caliper. (Refer to 5 - BRAKES - STANDARD PROCE-
DURE)
Fig. 35 Installing Piston Into Caliper Bore
1 - BOOT
2 - PISTON
3 - CALIPER
Fig. 36 Installing Dust Boot
1 - HAMMER
2 - SPECIAL TOOL C-4171
3 - SPECIAL TOOL C-4689 or C-4842
4 - CALIPER
RSBRAKES - BASE5-25
DISC BRAKE CALIPERS - FRONT (Continued)

(10) Road test the vehicle and make several stops
to wear off any foreign material on the brakes and to
seat the brake shoe linings.
INSTALLATION - FRONT DISC BRAKE CALIPER
(DISC/DRUM BRAKES)
CAUTION: TRW and Continental Teves brake cali-
pers are not interchangeable. Each caliper is specif-
ically designed for the unique brake system (TRW -
disc/drum brake combination and Continental Teves
- disc/disc brake combination). If calipers are inter-
changed, improper performance, noise and
increased stopping distance can occur.
(1) Completely retract the caliper piston back into
the bore of the caliper. Use a C-clamp to retract the
piston if necessary. Place a wood block over the pis-
ton before installing the C-clamp to avoid damaging
the piston.
CAUTION: Use care when installing the caliper onto
the disc brake adapter to avoid damaging the boots
on the caliper guide pins.
(2) Install the disc brake caliper over the brake
shoes on the brake caliper adapter.
(3) Align the caliper guide pin bolt holes with the
guide pins. Install the caliper guide pin bolts and
tighten them to a torque of 35 N´m (26 ft. lbs.) (Fig.
32).
(4) Install the banjo bolt connecting the brake hose
to the brake caliper (Fig. 32). Install NEW copper
washers on each side of the hose fitting as the banjo
bolt is guided through the fitting. Thread the banjo
bolt into the caliper and tighten it to a torque of 47
N´m (35 ft. lbs.).
(5) Install the tire and wheel assembly. Tighten
the wheel mounting nuts to a torque of 135 N´m (100
ft. lbs.).
(6) Lower the vehicle.
(7) Remove the brake pedal holding tool.
(8) Bleed the caliper as necessary. (Refer to 5 -
BRAKES - BASE - STANDARD PROCEDURE).
(9) Road test the vehicle and make several stops to
wear off any foreign material on the brakes and to
seat the brake shoes.
DISC BRAKE CALIPERS -
REAR
REMOVAL - REAR DISC BRAKE CALIPER
NOTE: Handling of the rotor and caliper, must be
done in such a way as to avoid damage to the rotorand scratching or nicking of lining on the brake
shoes.
(1) Depress the brake pedal past its first inch of
travel and hold it in this position using a brake pedal
depressor (holding) tool. This is done to isolate the
master cylinder from the brake hydraulic system dis-
allowing the brake fluid to completely drain out of
the brake fluid reservoir.
(2) Raise the vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(3) Remove rear wheel and tire assembly from
vehicle.
(4) Remove the banjo bolt connecting the brake
hose to the brake caliper. There are two washers (one
on each side of the brake hose fitting) that will come
off with the banjo bolt. Discard these washers.
(5) Remove the disc brake caliper to adapter guide
pin bolts (Fig. 37).
(6) Remove rear caliper from adapter using the fol-
lowing procedure. First rotate rear of caliper up from
the adapter. Then pull the front of the caliper and
the outboard brake shoe anti-rattle clip out from
under the front abutment on the adapter (Fig. 38).
(7) If the brake rotor requires removal, it can now
be removed by first removing the retainer clips from
the wheel mounting studs, then pulling the rotor
straight off the studs.
Fig. 37 Caliper Guide Pin Bolts
1 - DISC BRAKE CALIPER
2 - ADAPTER
3 - AXLE
4 - GUIDE PIN BOLTS
5 - DRIVESHAFT (AWD MODELS ONLY)
5 - 26 BRAKES - BASERS
DISC BRAKE CALIPERS - FRONT (Continued)

(6) Using a hammer and Installer, Special Tool
C-4689 or C-4842 (depending on piston size), and
Handle, Special Tool C-4171, drive the boot into the
counterbore of the caliper as necessary (Fig. 42).
(7) Reinstall the caliper on the vehicle and bleed
the brakes as necessary. Refer to Installation in this
section.
INSTALLATION - REAR DISC BRAKE CALIPER
(1) Completely retract caliper piston back into pis-
ton bore of the caliper.
(2) If removed, install the brake rotor on the hub,
making sure it is squarely seated on the face of the
hub.
CAUTION: Use care when installing the caliper
assembly onto the adapter, so the caliper guide pin
bushings do not get damaged by the mounting
bosses.
(3) Carefully lower caliper and brake shoes over
rotor and onto the adapter using the reverse proce-
dure for removal (Fig. 38).
CAUTION: When installing guide pin bolts extreme
caution should be taken not to cross-thread the cal-
iper guide pin bolts.(4) Install the caliper guide pin bolts. Tighten the
guide pin bolts to a torque of 35 N´m (26 ft. lbs.).
CAUTION: When connecting the brake hose to the
caliper, install new brake hose to caliper special
washers.
(5) Install the brake hose on the caliper. To do
this, first place one NEW special copper washer on
each side of the hose fitting, then slide the banjo bolt
through the fitting. Next, thread the banjo bolt into
the threaded port on the rear of the brake caliper.
Tighten the banjo bolt to a torque of 47 N´m (35 ft.
lbs.).
(6) Install the wheel and tire assembly.
(7) Tighten the wheel mounting stud nuts in
proper sequence until all nuts are torqued to half
specification. Then repeat the tightening sequence to
the full specified torque of 135 N´m (100 ft. lbs.).
(8) Lower the vehicle.
(9) Remove the brake pedal depressor (holding)
tool.
(10) Bleed the hydraulic brake circuit to the brake
caliper. (Refer to 5 - BRAKES - STANDARD PROCE-
DURE)
(11) Road test the vehicle and make several stops
to wear off any foreign material on the brakes and to
seat the brake shoe linings.
DISC BRAKE CALIPER
ADAPTER
REMOVAL - FRONT DISC BRAKE CALIPER
ADAPTER
(1) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(2) Remove front wheel and tire assembly, disc
brake caliper and brake shoes. (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/BRAKE PADS/SHOES
- REMOVAL)
(3) Remove two bolts fastening adapter to steering
knuckle, then remove disc brake caliper adapter.
INSTALLATION - FRONT DISC BRAKE CALIPER
ADAPTER
(1) Place adapter over brake rotor and align
adapter mounting holes to knuckle.
CAUTION: Adapter mounting bolts have a special
DacrometTcoating applied to resist corrosion. If
mounting bolts need to be replaced, use only
MoparTreplacement parts.
Fig. 42 Installing Dust Boot
1 - HAMMER
2 - SPECIAL TOOL C-4171
3 - SPECIAL TOOL C-4689 or C-4842
4 - CALIPER
RSBRAKES - BASE5-29
DISC BRAKE CALIPERS - REAR (Continued)

(2) Install adapter mounting bolts and tighten to
169 N´m (125 ft. lbs.) torque.
(3) Install brake shoes, disc brake caliper and
wheel and tire assembly. (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/BRAKE PADS/SHOES -
INSTALLATION)
(4) Lower vehicle.
(5) Pump the brake pedal several times to set the
pads to the brake rotor.
(6) Check and adjust brake fluid level as neces-
sary.
DISC BRAKE CALIPER GUIDE
PINS
REMOVAL - DISC BRAKE CALIPER GUIDE PINS
(DISC/DRUM BRAKES)
(1) Raise the vehicle. Refer to HOISTING in
LUBRICATION AND MAINTENANCE.
(2) Remove the front tire and wheel assembly.
(3) Remove the two brake caliper guide pin bolts
(Fig. 43).
(4) Remove the disc brake caliper from the disc
brake caliper adapter and hang it out of the way
using wire or a bungee cord. Use care not to overex-
tend the brake hose when doing this.
(5) Remove the guide pins and boots from the
adapter as shown (Fig. 44).
INSTALLATION - DISC BRAKE CALIPER GUIDE
PINS (DISC/DRUM BRAKES)
(1) Lubricate the guide pins and inside the boots
with the packet supplied with the service kit, Syth-
eso GLK-1 lubricant or equivalent.
(2) Install the guide pins and boots in the adapter
as shown (Fig. 44). The boots have grooves built into
their inner lips to fit onto the pins and adapter.
CAUTION: Use care when installing the caliper onto
the disc brake adapter to avoid damaging the boots
on the caliper guide pins.
(3) Install the disc brake caliper over the brake
shoes on the brake caliper adapter.
(4) Align the caliper guide pin bolt holes with the
guide pins. Install the caliper guide pin bolts and
tighten them to a torque of 35 N´m (26 ft. lbs.) (Fig.
43).
(5) Install the tire and wheel assembly. Tighten
the wheel mounting nuts to a torque of 135 N´m (100
ft. lbs.).
(6) Lower the vehicle.
(7) Pump the brake pedal several times before
moving the vehicle to set the shoes to the brake
rotor.
Fig. 43 Brake Caliper Mounting
1 - BRAKE HOSE
2 - ADAPTER MOUNTING BOLTS
3 - BANJO BOLT
4 - CALIPER GUIDE PIN BOLTS
Fig. 44 Guide Pins And Boots
1 - PINS
2 - BOOTS
5 - 30 BRAKES - BASERS
DISC BRAKE CALIPER ADAPTER (Continued)

DRUM
STANDARD PROCEDURE - BRAKE DRUM
MACHINING
Measure the runout and diameter of the rear brake
using only accurate measuring equipment. There
should be no variation in the drum diameter greater
than 0.090 mm (0.004 inch). Drum runout should not
exceed 0.15 mm (0.006 inch) out of round. If the
drum runout or diameter variation exceed these val-
ues the drum should be refaced. For best results in
eliminating the irregularities that cause brake rough-
ness and surge, the amount of material removed dur-
ing a single cut should be limited to 0.13 mm (0.005
inch). When the entire braking surface has been
cleaned, a final cut of 0.0254 mm (0.001 inch) will
assure a good drum surface providing the equipment
used is capable of the precision required for resurfac-
ing brake drums. Deeper cuts are permissible for the
sole purpose of removing deep score marks.Do not
reface more than 1.52 mm (0.060 inch) over the
standard drum diameter.
All drums will show markings of maximum allow-
able diameter (Fig. 45). For example, a drum will
have a marking of MAX. DIA. 251.55 mm (9.90 inch).
This marking includes 0.76 mm (0.030 inch) for
allowable drum wear beyond the recommended 1.52
mm (0.060 inch) of drum refacing.
REMOVAL
(1) Raise the vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
(2) Remove the tire and wheel assembly from the
vehicle(3) Remove the rear brake shoe adjusting hole
cover plug.
(4) Insert a thin screwdriver into brake adjusting
hole and hold adjusting lever away from notches of
adjusting screw star wheel.
(5) Insert another thin screwdriver into brake
adjusting hole and engage notches of brake adjusting
screw star wheel. Release brake adjustment by pry-
ing down with adjusting tool.
(6) Remove rear brake drum from rear hub/bear-
ing assembly.
INSTALLATION
(1) Adjust brake shoe assemblies so as not to inter-
fere with brake drum installation.
(2) Install the rear brake drums on the hubs.
(3) Adjust drum brake shoes as necessary per pro-
cedure found in the Adjustment section of this ser-
vice manual group (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/DRUM -
ADJUSTMENTS).
(4) Install wheel and tire assembly.
(5) Tighten the wheel mounting stud nuts in
proper sequence until all nuts are torqued to half
specification. Then repeat the tightening sequence to
the full specified torque of 135 N´m (100 ft. lbs.).
(6) Lower the vehicle.
FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION
Indications of fluid contamination are swollen or
deteriorated rubber parts.
Swollen rubber parts indicate the presence of
petroleum in the brake fluid.
To test for contamination, put a small amount of
drained brake fluid in clear glass jar. If fluid sepa-
rates into layers, there is mineral oil or other fluid
contamination of the brake fluid.
If brake fluid is contaminated, drain and thor-
oughly flush system. Replace master cylinder, propor-
tioning valve, caliper seals, wheel cylinder seals,
Antilock Brake hydraulic unit and all hydraulic fluid
hoses.
Fig. 45 Rear Brake Drum Maximum Diameter
Identification
1 - MAXIMUM DIAMETER OF BRAKE DRUM SHOWN ON THIS
SURFACE
2 - BRAKE DRUM
RSBRAKES - BASE5-31

STANDARD PROCEDURE - BRAKE FLUID
LEVEL CHECKING
Check master cylinder reservoir fluid level a mini-
mum of twice annually.
Fluid reservoirs are marked with the words FULL
and ADD to indicate proper brake fluid fill level of
the master cylinder.
If necessary, add brake fluid to bring the level to
the bottom of the FULL mark on the side of the mas-
ter cylinder fluid reservoir.
Use only Mopartbrake fluid or equivalent from a
sealed container. Brake fluid must conform to DOT 3
specifications (DOT 4 or DOT 4+ are acceptable).
DO NOTuse brake fluid with a lower boiling
point, as brake failure could result during prolonged
hard braking.
Use only brake fluid that was stored in a tightly-
sealed container.
DO NOTuse petroleum-based fluid because seal
damage will result. Petroleum based fluids would be
items such as engine oil, transmission fluid, power
steering fluid etc.
SPECIFICATIONS
BRAKE FLUID
The brake fluid used in this vehicle must conform
to DOT 3 specifications (DOT 4 and DOT 4+ are
acceptable) and SAE J1703 standards. No other type
of brake fluid is recommended or approved for usage
in the vehicle brake system. Use only MopartBrake
Fluid or equivalent from a tightly sealed container.
CAUTION: Never use reclaimed brake fluid or fluid
from an container which has been left open. An
open container of brake fluid will absorb moisture
from the air and contaminate the fluid.
CAUTION: Never use any type of a petroleum-based
fluid in the brake hydraulic system. Use of such
type fluids will result in seal damage of the vehicle
brake hydraulic system causing a failure of the
vehicle brake system. Petroleum based fluids would
be items such as engine oil, transmission fluid,
power steering fluid, etc.
JUNCTION BLOCK
DESCRIPTION - NON-ABS JUNCTION BLOCK
A junction block is used on vehicles that are not
equipped with antilock brakes (ABS). The junction
block mounts in the same location as the integrated
control unit (ICU) does on vehicles equipped withABS. This allows for use of the same brake tube con-
figuration on all vehicles. The junction block is
located on the driver's side of the front suspension
cradle/crossmember below the master cylinder (Fig.
46).
It has six threaded ports to which the brake tubes
connect. Two are for the primary and secondary
brake tubes coming from the master cylinder. The
remaining four are for the chassis brake tubes going
to each brake assembly.
OPERATION - NON-ABS JUNCTION BLOCK
The junction block distributes the brake fluid com-
ing from the master cylinder primary and secondary
ports to the four chassis brake tubes leading to the
brakes at each wheel. Since the junction block
mounts in the same location as the ABS integrated
control unit (ICU), it allows for the common use of
brake tubes going to the brakes whether the vehicle
is equipped with or without ABS.
NOTE: Although the brake tubes coming from the
master cylinder to the junction block or ABS ICU
may appear to be the same, they are not. They are
unique to each brake system application.
REMOVAL - NON-ABS JUNCTION BLOCK
(1) Using a brake pedal depressor, move and lock
the brake pedal to a position past its first 1 inch of
travel. This will prevent brake fluid from draining
out of the master cylinder when the brake tubes are
removed from the junction block.
(2) Disconnect the battery negative cable.
(3) If the vehicle is equipped with speed control,
perform the following:
(a) Disconnect the battery positive cable.
(b) Remove the battery (Refer to 8 - ELECTRI-
CAL/BATTERY SYSTEM/BATTERY - REMOVAL).
(c) Disconnect the vacuum hose connector at the
tank built into the battery tray.
(d) Remove the screw securing the coolant filler
neck to the battery tray.
(e) Remove the battery tray (Refer to 8 - ELEC-
TRICAL/BATTERY SYSTEM/TRAY - REMOVAL).
(f) Remove the fasteners and move the speed
control servo off to the side, out of the way.
CAUTION: Before removing the brake tubes from
the junction block, the junction block and the brake
tubes must be thoroughly cleaned. This is required
to prevent contamination from entering the brake
hydraulic system.
5 - 32 BRAKES - BASERS
FLUID (Continued)

For information on master cylinder application,
bore and type, view the following table:
BRAKE SYSTEMMASTER CYLINDER
BORE/TYPE
Disc/Drum - ABS23.8 mm Conventional
Compensating Port
Disc/Drum - Non-ABS23.8 mm Conventional
Compensating Port
Disc/Disc - ABS25.4 mm (1-1/16 in.)
Conventional
Compensating Port
Disc/Disc ABS With
Traction Control25.4 mm (1-1/16 in.) Dual
Center Port
CAUTION: When replacing a master cylinder, be
sure to use the correct master cylinder for the type
of brake system the vehicle is equipped with.
The body of the master cylinder is an anodized alu-
minum casting. It has a machined bore to accept the
master cylinder pistons and threaded ports with
seats for the hydraulic brake line connections.
The brake fluid reservoir is mounted on the top of
the master cylinder. It is made of a see-through
polypropylene type plastic for easy fluid level view-
ing. A brake fluid level switch is attached to the
brake fluid reservoir.
The master cylinder is not a repairable component
and must be replaced if diagnosed to be functioning
improperly. The brake fluid reservoir and brake fluid
level switch can be replaced separately.
CAUTION: Do not hone the bore of the cylinder as
this will remove the anodized surface from the bore.
OPERATION
When the brake pedal is depressed, the master cyl-
inder primary and secondary pistons apply brake
pressure through the chassis tubes to the brakes at
each tire and wheel assembly.
The master cylinder primary outlet port supplies
hydraulic pressure to the right front and left rear
brakes. The secondary outlet port supplies hydraulic
pressure to the left front and right rear brakes.
STANDARD PROCEDURE - MASTER CYLINDER
BLEEDING
CAUTION: When clamping master cylinder in vise,
only clamp master cylinder by its mounting flange,
do not clamp on primary piston, seal or body of
master cylinder.(1) Clamp the master cylinder in a vise using only
the mounting flange.
NOTE: Two different size bleeding tubes need to be
used depending on which type of master cylinder
the vehicle is equipped with. Vehicles equipped
with traction control have different size brake tubes
and nuts at the master cylinder than the non-trac-
tion control equipped vehicles. Be sure the correct
size bleeding tubes are used when bleeding the
master cylinder.
(2) Thread Bleeding Tubes, Special Tool 8358, for a
non-traction control master cylinder or Special Tool
8129 for a traction control master cylinder into mas-
ter cylinder primary and secondary ports. Position
outlet ends of bleeding tubes in reservoir with the
outlets below surface of brake fluid when reservoir is
filled to its proper level.
(3) Fill brake fluid reservoir with Mopartbrake
fluid or equivalent conforming to DOT 3 (DOT 4 and
DOT 4+ are acceptable) specifications.
(4) Using a wooden dowel, depress push rod slowly,
and then allow pistons to return to released position.
Repeat several times until all air bubbles are
expelled from master cylinder.
(5) Remove bleeding tubes from master cylinder
outlet ports, and then plug outlet ports and install
fill cap on reservoir.
(6) Remove master cylinder from vise.
(7) Install the filler cap on master cylinder fluid
reservoir.
(8) Install master cylinder. (Refer to 5 - BRAKES -
BASE/HYDRAULIC/MECHANICAL/MASTER CYL-
INDER - INSTALLATION)
REMOVAL - MASTER CYLINDER
CAUTION: Vacuum in the power brake booster must
be pumped down (removed) before removing mas-
ter cylinder from power brake booster. This is nec-
essary to prevent the power brake booster from
sucking in any contamination as the master cylin-
der is removed. This can be done simply by pump-
ing the brake pedal, with the vehicle's engine not
running, until a firm feeling brake pedal is achieved.
(1) With engine not running, pump brake pedal
until a firm pedal is achieved (4-5 strokes).
(2) Disconnect negative battery terminal.
(3) Disconnect positive battery terminal.
(4) Remove battery shield.
(5) Remove nut and clamp securing battery to tray,
remove battery.
5 - 34 BRAKES - BASERS
MASTER CYLINDER (Continued)

OPERATION - PROPORTIONING VALVE
(HEIGHT SENSING)
Vehicles not equipped with ABS use a height sens-
ing proportioning valve.
The height sensing proportioning valve operates
similarly to a standard proportioning valve in the fol-
lowing way. As hydraulic pressure is applied to the
valve, full input hydraulic pressure is supplied to the
rear brakes up to a certain pressure point, called the
split point. Beyond the split point, the proportioning
valve reduces the amount of hydraulic pressure to
the rear brakes according to a given ratio. Thus, on
light brake applications, approximately equal
hydraulic pressure will be transmitted to both the
front and rear brakes. Upon heavier brake applica-
tions, the hydraulic pressure transmitted to the rear
brakes will be lower than the front brakes. This will
prevent premature rear wheel lockup and skid.
Here is how the height sensing proportioning valve
differs from a standard proportioning valve. As the
height of the rear suspension changes, the height
sensing portion of the proportioning valve changes
the split point of the proportioning valve. When the
height of the rear suspension is low, the proportion-
ing valve interprets this as extra load and the split
point of the proportioning valve is raised to a higher
pressure to allow for more rear braking. When the
height of the rear suspension is high, the proportion-
ing valve interprets this as a light load and the split
point of the proportioning valve is lowered to a lower
pressure and rear braking is reduced.
The height sensing proportioning valve regulates
the pressure by sensing the load condition of thevehicle through the movement of the proportioning
valve actuator lever (Fig. 61). As the position of the
rear axle changes, depending on the load the vehicle
is carrying, the movement is transferred to the pro-
portioning valve. The proportioning valve adjusts the
hydraulic pressure accordingly.
The height sensing proportioning valve allows the
brake system to maintain the optimal front to rear
brake balance regardless of the vehicle load condi-
tion. Under a light load condition, hydraulic pressure
to the rear brakes is minimized. As the rear load con-
dition increases, so does the hydraulic pressure to
the rear brakes.
DIAGNOSIS AND TESTING - PROPORTIONING
VALVE (HEIGHT SENSING)
CAUTION: The use of aftermarket load leveling or
load capacity increasing devices on this vehicle is
prohibited. Using air shock absorbers or helper
springs on this vehicle will cause the height sens-
ing proportioning valve to inappropriately reduce
the hydraulic pressure to the rear brakes. This inap-
propriate reduction in hydraulic pressure potentially
could result in increased stopping distance of the
vehicle.
When a premature rear wheel skid is obtained on a
brake application, it may be an indication that the
hydraulic pressure to the rear brakes is above the
specified output from the proportioning valve. This
condition indicates a possible malfunction of the
height sensing proportioning valve, which will
require testing to verify that it is properly controlling
the hydraulic pressure allowed to the rear brakes.
Premature rear wheel skid may also be caused by
contaminated front or rear brake linings.
Prior to testing a proportioning valve for function,
check that all tire pressures are correct. Also, ensure
the front and rear brake linings are in satisfactory
condition.It is also necessary to verify that the
brakes shoe assemblies on a vehicle being
tested are either original equipment manufac-
turers (OEM) or original replacement brake
shoe assemblies meeting the OEM lining mate-
rial specification. This vehicles brake system is
not balanced for aftermarket brake shoe assem-
bly lining material.
If both front and rear brakes check OK, proceed
with the following test procedure for the height sens-
ing proportioning valve.
(1) Road test the vehicle to determine which rear
wheel brake is exhibiting premature wheel skid.
Fig. 61 HEIGHT SENSING PROPORTIONING VALVE
1 - PROPORTIONING VALVE
2 - ACTUATOR LEVER
3 - AXLE BRACKET
4 - REAR AXLE
5 - 42 BRAKES - BASERS
PROPORTIONING VALVE (Continued)

(2) Raise vehicle. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE)
(3) Remove the chassis brake tube going to the
rear brake in question at the proportioning valve.
Remove the chassis brake tube coming from the junc-
tion block at the proportioning valve (Fig. 62).
(4) Install the appropriate fittings from Pressure
Test Fittings, Special Tool 6833, into the open ports
of the proportioning valve.
(5) Install the previously removed brake lines into
the Pressure Test Fittings. Tighten all tube nuts to
17 N´m (145 in. lbs.).
(6) Install a pressure gauge from Gauge Set, Spe-
cial Tool C-4007-A into the open port on each pres-
sure test fitting. Bleed air out of hose from pressure
test fittings to pressure gauges at the pressure
gauges. Then bleed air out of the brake line being
tested at that rear wheel brake bleeder.
(7) Remove the screw fastening the proportioning
valve actuator lever bracket to the rear axle. Raise
the actuator lever to the full-upward position.
(8) With the aid of a helper, apply pressure to the
brake pedal until a pressure of 6895 kPa (1000 psi) is
obtained on the proportioning valve inlet gauge.
Then, based on the type of brake system the vehicleis equipped with and the pressure specification
shown on the following table, compare the pressure
reading on the outlet gauge to the specification. If
outlet pressure at the proportioning valve is not
within specification when required inlet pressure is
obtained, replace the proportioning valve. (Refer to 5
- BRAKES/HYDRAULIC/MECHANICAL/PROPOR-
TIONING VALVE - REMOVAL)
CAUTION: Do not attempt to adjust the height sens-
ing proportioning valve. If found to be defective,
replace the valve.
(9) Remove the pressure test fittings and pressure
gauges from the proportioning valve.
(10) Install the chassis brake lines in the correct
ports of the proportioning valve. Tighten all tube
nuts to 17 N´m (145 in. lbs.).
(11) If necessary, repeat the above steps on the
remaining side of the proportioning valve which con-
trol the other rear wheel brake.
(12) Attach the actuator lever and bracket to the
rear axle.
(13) Bleed rear brakes. (Refer to 5 - BRAKES -
STANDARD PROCEDURE)
(14) Road test vehicle.
WHEEL
BASEDRIVE
TRAINSALES CODE BRAKE SYSTEMSPLIT
POINTSLOPEINLET
PRESSURE
PSIOUTLET
PRESSURE
PSI
SWB FWD BRB-BGF159DISC/DRUM
W/O ANTILOCKVAR. .59 1000 PSI 675-875 PSI
REMOVAL - PROPORTIONING VALVE (HEIGHT
SENSING)
(1) Using a brake pedal depressor, move and lock
the brake pedal to a position past its first 1 inch of
travel. This will prevent brake fluid from draining
out of the master cylinder when the brake tubes are
removed from the proportioning valve.
(2) Raise vehicle on jackstands or centered on a
hoist. (Refer to LUBRICATION & MAINTENANCE/
HOISTING - STANDARD PROCEDURE).
CAUTION: Before removing the brake tubes from
the proportioning valve, the proportioning valve and
the brake tubes must be thoroughly cleaned. This is
required to prevent contamination from entering the
proportioning valve or the brake tubes.
(3) Remove the four brake tubes from the inlet and
outlet ports of the proportioning valve (Fig. 62).
(4) Remove the two bolts attaching the proportion-
ing valve and bracket to the vehicle (Fig. 62).(5) Slide the bracket out from under rear track bar
bracket. Lower the valve down enough to pull its
actuator lever out of the axle bracket and remove the
proportioning valve from the vehicle.
INSTALLATION - PROPORTIONING VALVE
(HEIGHT SENSING)
(1) Install the end of the actuator lever through
the axle bracket grommet and slide the proportioning
valve bracket under the rear track bar body bracket
(Fig. 62).
(2) Install the proportioning valve attaching bolts
(Fig. 62). Tighten the attaching bolts to a torque of
54 N´m (40 ft. lbs.).
(3) Install the four chassis brake lines into the
inlet and outlet ports of the proportioning valve (Fig.
62). Tighten all tube nuts to a torque of 17 N´m (145
in. lbs.).
CAUTION: The height sensing proportioning valve
is not adjustable. No attempt should be made to
adjust it.
RSBRAKES - BASE5-43
PROPORTIONING VALVE (Continued)