Rear system CHRYSLER VOYAGER 2005 User Guide

Follow pressure bleeder manufacturer's instruc-
tions for use of pressure bleeding equipment.
(1) Install the Adapter Master Cylinder Pressure
Bleed Cap, Special Tool 6921 on the fluid reservoir of
the master cylinder (Fig. 2). Attach the fluid hose
from the pressure bleeder to the fitting on Special
Tool 6921.
(2) Attach a clear plastic hose to the bleeder screw
at one wheel and feed the hose into a clear jar con-
taining fresh brake fluid.
(3) Open the left rear wheel bleeder screw at least
one full turnor more to obtain an adequate flow of
brake fluid.
CAUTION: ªJust crackingº the bleeder screw often
restricts fluid flow, allowing only a slow, weak fluid
discharge of fluid. This practice will NOT get all the
air out. Make sure the bleeder is opened at least 1
full turn when bleeding.
(4) After 4 to 8 ounces of brake fluid has been bled
through the hydraulic system, and an air-free flow is
maintained in the hose and jar, this will indicate a
good bleed of the hydraulic system has been
obtained.
(5) Repeat the procedure at all the other remain-
ing bleeder screws.
(6) Check pedal travel. If pedal travel is excessive
or has not been improved, enough fluid has not
passed through the system to expel all the trapped
air. Be sure to monitor the fluid level in the pressure
bleeder, so it stays at a proper level so air will not
enter the brake system through the master cylinder.
(7) Perform a final adjustment of the rear brake
shoes (when applicable), then test drive vehicle to be
sure brakes are operating correctly and that pedal is
solid.SPECIFICATIONS
BRAKE FASTENER TORQUE
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
ABS ICU Mounting Bolts To
Bracket11 Ð 9 7
ABS ICU Mounting
Bracket-To-Cradle Bolts28 21 250
ABS CAB-To-HCU Mounting
Screws2Ð17
ABS Wheel Speed Sensor
Head Mounting Bolt - Front13 Ð 115
ABS Wheel Speed Sensor
Head Mounting Bolt - Rear10 Ð 90
Adjustable Pedal Position
Sensor Mounting Screws7.5 66 Ð
Adjustable Pedal Module
Mounting Screws2.0 15 Ð
Brake Tube Nuts 17 Ð 145
Brake Hose Intermediate
Bracket Bolt12 Ð 105
Brake Hose-To-Caliper
Mounting Bolt47 35 Ð
Disc Brake Caliper Guide
Pin Bolts35 26 Ð
Disc Brake Caliper Bleeder
Screw15 Ð 125
Drum Brake Wheel Cylinder
Mounting Bolts8Ð75
Drum Brake Wheel Cylinder
Mounting Bleeder screw10 Ð 80
Drum Brake Support Plate
Mounting Bolts130 95 Ð
Junction Block (Non-ABS
Brakes) Mounting Bolts28 21 250
Master Cylinder Mounting
Nuts25 19 225
Power Brake Booster
Mounting Nuts28 21 250
Proportioning Valve
Mounting Bolts54 40 Ð
Proportioning Valve Axle
Bracket Mounting Bolt20 Ð 175
Parking Brake Lever (Pedal)
Mounting Bolts And Nut28 21 250
Wheel Mounting (Lug) Nuts 135 100 Ð
Fig. 2 Tool 6921 Installed On Master Cylinder
1 - SPECIAL TOOL 6921
2 - FLUID RESERVOIR
RSBRAKES - BASE5-9
BRAKES - BASE (Continued)

The Continental Teves front brake caliper is a one
piece casting containing a single piston 66 mm diam-
eter bore (Fig. 4) with a phenolic piston. The caliper
mounts to a caliper adapter using two guide pin bolts
that thread into the caliper adapter and slide on
bushings mounted in the caliper.
CAUTION: TRW and Continental Teves calipers are
not interchangeable. Each caliper is specifically
designed for the unique brake system. If calipers
are interchanged, improper performance, noise and
increased stopping distance can occur.
The two different brake calipers use different
devices to control rattling. While the TRW brakes use
spring clips that mount at the ends of the shoes in
the adapters, Continental Teves brakes use a clip on
the rear of the inboard pad to hold it to the piston
and a larger clip on the outside of the caliper, holding
it to the adapter (Fig. 6).
All brake caliper adapters mount to the steering
knuckle in the same way using two mounting bolts.
The brake rotors are also different depending on
brake system. The TRW front brakes utilize an
inverted-hat style rotor. This rotor is externally
vented meaning the inner most diameter of the brak-
ing disc vents to the outboard side (or face) of the
rotor (Fig. 7). The Continental Teves front brakes uti-
lize the familiar internally-vented hat style rotor.
Internally-vented refers to the fact that the inner
most diameter of the braking disc vents to the
inboard side of the rotor (Fig. 7).CAUTION: Do not mix rotor types on the same vehi-
cle. If brake rotors are mixed, noise and wear prob-
lems can result.
Fig. 5 Guide Pins And Boots
1 - PINS
2 - BOOTSFig. 6 Anti-Rattle Devices On Calipers
1 - CONTINENTAL TEVES CALIPER
2 - TRW CALIPER
3 - ANTI-RATTLE CLIP
4 - ANTI-RATTLE CLIP
Fig. 7 Externally and Internally Vented Rotors
(Cross-Sectional View)
1 - EXTERNAL VENTS (TRW and Continental Teves BR3)
2 - INTERNAL VENTS (Continental Teves BRE)
5 - 12 BRAKES - BASERS
HYDRAULIC/MECHANICAL (Continued)

DESCRIPTION - DISC BRAKES (REAR)
There are several distinctive features to the rear
disc brakes on this vehicle (Fig. 8). The single piston,
floating caliper rear disc brake system includes a hub
and bearing assembly, adapter, rotor, caliper, and
brake shoes.
This vehicle is equipped with a caliper having a 42
mm (1.65 in.) piston and uses a 15 inch solid non-
vented brake rotor. The brake rotor is described as a
drum-in-hat style because of its dual role as a brak-
ing disc and parking brake drum.
The parking brake system on vehicles equipped
with rear disc brakes consists of a small duo-servo
drum brake mounted to the caliper adapter and uses
the interior of the rear disc brake rotor as a drum
(hat section of drum-in-hat style brake rotor).
The outboard rear disc brake shoes (pads) are side-
oriented. The shoes are marked indicating which side
they belong on.
DESCRIPTION - DISC BRAKES (EXPORT)
All vehicles are equipped with Four-Wheel-Disc
brakes. Both 15º (BRE) and 16º (BR3) disc/disc brake
systems are available. The disc brakes are manufac-
tured by Continental Teves. The BR3 system is stan-
dard equipment on all-wheel drive and all right-hand
drive models. It is optional on other models.
The BR3 system features larger, externally vented
front brake rotors.
Although there are different disc/disc systems, they
are serviced using the same service procedures. Some
specifications differ.
DESCRIPTION - DRUM BRAKES (REAR)
This vehicle's rear wheel drum brakes are a two-
shoe, internal-expanding type with an automatic
adjuster screw. The automatic adjuster screw is
located directly below the wheel cylinder that is
mounted near the top of the brake assembly (Fig. 9).
These and two brake shoes (and attaching parts) are
mounted to a support plate at each rear wheel. A
brake drum covers each brake assembly.
OPERATION
OPERATION - DISC BRAKES (FRONT)
When the brakes are applied, fluid pressure is sent
to each brake caliper. The pressure at the caliper is
exerted equally against the caliper piston. The pres-
sure applied to the piston is transmitted directly to
the inboard brake shoe. This forces the shoe lining
against the inner surface of the brake rotor. At the
same time, fluid pressure within the caliper piston
bore forces the caliper to slide inward on its guide
pins. This action brings the outboard shoe lining into
contact with the outer surface of the brake rotor.
This pressure on both sides of the brake rotor causes
friction, bringing the vehicle to a stop.
When the brake pedal is released, so is the fluid
pressure. The piston seal inside the caliper is
designed to pull the piston back into the bore of the
caliper when the brake pedal is released (Fig. 10).
This action helps maintain the proper brake shoe-to-
rotor clearance.
Fig. 8 Rear Disc Brakes
1 - CALIPER
2 - COTTER PIN
3 - ROTOR
4 - NUT RETAINER
5 - OUTER C/V JOINT
Fig. 9 Drum Brake Assembly (Right Shown)
1 - WHEEL CYLINDER
2 - BRAKE SHOE UPPER RETURN SPRING
3 - AUTOMATIC ADJUSTER LEVER
4 - TENSION CLIP
5 - AUTOMATIC ADJUSTER ASSEMBLY
RSBRAKES - BASE5-13
HYDRAULIC/MECHANICAL (Continued)

As disc brake shoe linings wear, master cylinder
reservoir brake fluid level will drop. Adjust as neces-
sary. Fluid level should always be checked after
replacing shoes.
OPERATION - DISC BRAKES (REAR)
The rear disc brakes operate similarly to front disc
brakes, however, there are some features that require
different service procedures.
DIAGNOSIS AND TESTING - DRUM BRAKE
AUTOMATIC ADJUSTER
The rear drum brakes on this vehicle automatically
adjust when required during the normal operation of
the vehicle every time the brakes are applied. Use
the following procedure to test the operation of the
automatic adjuster.
Place the vehicle on a hoist with a helper in the
driver's seat to apply the brakes. Remove the access
plug from the adjustment hole in each brake support
plate to provide visual access of the brake adjuster
star wheel.
To eliminate the condition where maximum adjust-
ment of the rear brake shoes does not allow the auto-
matic adjuster to operate when tested, back the star
wheel off approximately 30 notches. It will be neces-
sary to hold the adjuster lever away from the star
wheel to permit this adjustment.
Have the helper apply the brakes. Upon applica-
tion of the brake pedal, the adjuster lever should
move down, turning the adjuster star wheel. Thus, a
definite rotation of the adjuster star wheel can be
observed if the automatic adjuster is working prop-
erly. If one or more adjusters do not function prop-
erly, the respective drum must be removed for
adjuster servicing.
BRAKE LINES
DESCRIPTION - BRAKE TUBES AND HOSES
The brake tubes are steel with a corrosion-resis-
tant nylon coating applied to the external surfaces.
The flex hoses are made of reinforced rubber with fit-
tings at each end.
The primary and secondary brake tubes leading
from the master cylinder to the ABS ICU Hydraulic
Control Unit (HCU) or the non-ABS junction block
have a special flexible section. This flexible section is
required due to cradle movement while the vehicle is
in motion (The ICU and non-ABS junction block are
mounted to the cradle).If replacement of these
lines is necessary, only the original factory
brake line containing the flexible section must
be used.
OPERATION - BRAKE TUBES AND HOSES
The purpose of the chassis brake tubes and flex
hoses is to transfer the pressurized brake fluid devel-
oped by the master cylinder to the wheel brakes of
the vehicle. The flex hoses are made of rubber to
allow for the movement of the vehicle's suspension.
INSPECTION - BRAKE TUBES AND HOSES
Flexible rubber hose is used at both front brakes
and at the rear axle. Inspection of brake hoses
should be performed whenever the brake system is
serviced and every 7,500 miles or 12 months, which-
ever comes first (every engine oil change). Inspect
hydraulic brake hoses for surface cracking, scuffing,
or worn spots. If the fabric casing of the rubber hose
becomes exposed due to cracks or abrasions in the
rubber hose cover, the hose should be replaced imme-
diately. Eventual deterioration of the hose can take
place with possible burst failure. Faulty installation
can cause twisting, resulting in wheel, tire, or chassis
interference.
The brake tubing should be inspected periodically
for evidence of physical damage or contact with mov-
ing or hot components.
The flexible brake tube sections used on this vehi-
cle in the primary and secondary tubes from the
master cylinder to the ABS hydraulic control unit
connections must also be inspected. This flexible tub-
ing must be inspected for kinks, fraying and contact
with other components or with the body of the vehi-
cle.
Fig. 10 Caliper Piston Seal Function For Automatic
Adjustment
1 - PISTON
2 - CYLINDER BORE
3 - PISTON SEAL BRAKE PRESSURE OFF
4 - CALIPER HOUSING
5 - DUST BOOT
6 - PISTON SEAL BRAKE PRESSURE ON
5 - 14 BRAKES - BASERS
HYDRAULIC/MECHANICAL (Continued)

INSTALLATION
INSTALLATION - FRONT DISC BRAKE CALIPER
(CONTINENTAL TEVES BRAKES)
CAUTION: TRW and Continental Teves brake cali-
pers are not interchangeable. Each caliper is specif-
ically designed for the unique brake system. If
calipers are interchanged, improper performance,
noise and increased stopping distance can occur.
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL -
DESCRIPTION)
(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)(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
(TRW BRAKES)
CAUTION: TRW and Continental Teves brake cali-
pers are not interchangeable. Each caliper is specif-
ically designed for the unique brake system. If
calipers are interchanged, improper performance,
noise and increased stopping distance can occur.
(Refer to 5 - BRAKES/HYDRAULIC/MECHANICAL -
DESCRIPTION)
(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.
31).
(4) Install the banjo bolt connecting the brake hose
to the brake caliper (Fig. 31). 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.
RSBRAKES - BASE5-27
DISC BRAKE CALIPER - FRONT (Continued)

DISC BRAKE CALIPER - 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 rotor
and 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. 36).
(6) Remove rear caliper from adapter using the fol-
lowing procedure. First rotate front of caliper up
from the adapter. Then pull the rear of the caliper
and the outboard brake shoe anti-rattle clip out from
under the rear abutment on the adapter (Fig. 37).
(7) If the brake rotor requires removal, it can now
be removed by first removing the retainer clips fromthe wheel mounting studs, then pulling the rotor
straight off the studs.
DISASSEMBLY - CALIPER PISTON AND SEAL
WARNING: UNDER NO CONDITION SHOULD HIGH
PRESSURE AIR EVER BE USED TO REMOVE A PIS-
TON FROM A CALIPER BORE. PERSONAL INJURY
COULD RESULT FROM SUCH A PRACTICE.
NOTE: Before disassembling the brake caliper,
clean and inspect it. Refer to CLEANING AND
INSPECTION in this section.
NOTE: The safest way to remove the piston from
the caliper bore is to use the hydraulic pressure of
the vehicle's brake system.
(1) Following the removal procedure in DISC
BRAKE SHOES found in this section, remove the
caliper from the brake rotor and hang the assembly
on a wire hook away from rotor and body of the vehi-
cle so brake fluid cannot get on these components.
Remove the brake shoes, and place a small piece of
wood between the piston and caliper fingers.
(2) Carefully depress the brake pedal to hydrauli-
cally push piston out of its bore. Once completed,
apply and hold down the brake pedal to any position
beyond the first inch of pedal travel using a brake
pedal holding tool. This will prevent the fluid in the
master cylinder reservoir from completely draining
out.
Fig. 36 Caliper Guide Pin Bolts
1 - DISC BRAKE CALIPER
2 - ADAPTER
3 - AXLE
4 - GUIDE PIN BOLTS
5 - DRIVESHAFT (AWD MODELS ONLY)
Fig. 37 Removing/Installing Caliper
1 - LIFT THIS END OF CALIPER AWAY FROM ADAPTER FIRST
2 - DISC BRAKE CALIPER
3 - ADAPTER ABUTMENT
4 - OUTBOARD BRAKE SHOE HOLD DOWN CLIP
5 - OUTBOARD BRAKE SHOE
6 - ROTOR
7 - ADAPTER
5 - 28 BRAKES - BASERS

CAUTION: When tightening the primary and sec-
ondary brake tube nuts at master cylinder, be sure
brake tubes do not contact any other components
within the vehicle and that there is slack in the flex-
ible sections of the tubes. This is required due to
the movement between the ABS ICU and the master
cylinder while the vehicle is in motion.
(4) Connect primary and secondary brake tubes to
master cylinder primary and secondary ports (Fig.
50). Brake tubes must be held securely when tight-
ened to control orientation of flex section. Tighten
tube nuts to a torque of 17 N´m (145 in. lbs.).
(5) Install wiring harness connector to brake fluid
level switch mounted in brake fluid reservoir (Fig.
46).
(6) Install battery, clamp and nut.
(7) Install battery shield.
(8) Connect positive battery terminal.
(9) Connect negative battery terminal.
(10) Fill master cylinder with clean, fresh Mopart
Brake Fluid or equivalent.
(11) Road test vehicle to ensure proper operation of
brakes.
PEDALS - ADJUSTABLE
REMOVAL
NOTE: Before proceeding, review all Steering Col-
umn and Airbag Warnings and Cautions. (Refer to
19 - STEERING/COLUMN - WARNING)(Refer to 8 -
ELECTRICAL/RESTRAINTS - WARNING)
(1) Move driver's seat to full rearward position.
(2) Disconnect negative battery cable from battery
post and isolate.
(3) Remove throttle cable from throttle body lever.
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
THROTTLE CONTROL CABLE - REMOVAL)
(4) Remove screws securing lower steering column
cover/knee blocker, then remove it (Fig. 53).
(5) Disconnect parking brake release link at
release handle.
(6) Compress tabs on sides of data link diagnostic
connector and remove it from knee blocker reinforce-
ment plate.
(7) Remove screws securing knee blocker reinforce-
ment plate in place, then remove reinforcement plate
(Fig. 53).
(8) Remove hood release from lower left reinforce-
ment.
(9) Remove screws securing instrument panel
lower left reinforcement in place, then remove rein-
forcement (Fig. 54).(10) Remove brake lamp switch.Discard original
switch; it must not be reused.(Refer to 8 - ELEC-
TRICAL/LAMPS/LIGHTING - EXTERIOR/BRAKE
LAMP SWITCH - REMOVAL)
(11) Remove upper and lower steering column
shrouds. (Refer to 19 - STEERING/COLUMN/
LOWER SHROUD - REMOVAL)
Fig. 53 Lower Steering Column Cover And
Reinforcement
1 - INSTRUMENT PANEL
2 - REINFORCEMENT PLATE
3 - LOWER STEERING COLUMN COVER/KNEE BLOCKER
Fig. 54 Instrument Panel Lower Left Reinforcement
1 - INSTRUMENT PANEL LOWER REINFORCEMENT
2 - STEERING WHEEL
3 - LOWER LEFT REINFORCEMENT
5 - 40 BRAKES - BASERS
MASTER CYLINDER (Continued)

PROPORTIONING VALVE
DESCRIPTION - PROPORTIONING VALVE
(HEIGHT SENSING)
NOTE: Only vehicles without antilock brakes (ABS)
have a proportioning valve. Vehicles with ABS uti-
lize electronic brake distribution which is controlled
through the ABS integrated control unit.
Vehicles not equipped with ABS use a height sens-
ing proportioning valve. It is mounted to the body of
the vehicle above the rear axle (Fig. 80). It has an
actuator lever that attaches to the rear axle and
moves with the axle to help the valve sense the vehi-
cle height.
CAUTION: The height sensing proportioning valve
is not adjustable. No attempt should be made to
adjust it. It is replaced as a complete assembly.
CAUTION: The use of after-market load leveling or
load capacity increasing devices on this vehicle are
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.
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 the
vehicle through the movement of the proportioning
valve actuator lever (Fig. 80). 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.
Fig. 80 HEIGHT SENSING PROPORTIONING VALVE
1 - PROPORTIONING VALVE
2 - ACTUATOR LEVER
3 - AXLE BRACKET
4 - REAR AXLE
RSBRAKES - BASE5-53

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.
(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. 81).
(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.
NOTE: Actuator rod is a linear spring and is meant
to flex by design. When rod is raised, it will have
some curvature to it.
(7) Remove the screw fastening the proportioning
valve actuator rod bracket to the rear axle. Raise the
actuator lever to the full-upward position and hold it
there.
(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 vehicle
is 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.
5 - 54 BRAKES - BASERS
PROPORTIONING VALVE (Continued)

PROPORTIONING VALVE SPECIFICATIONS
WHEEL
BASEDRIVE
TRAINSALES
CODEBRAKE
SYSTEMSPLIT
POINTSLOPEINLET
PRESSURE
PSIOUTLET
PRESSURE
PSI
SWB FWD BRB-BGF159DISC/
DRUM W/O
ANTILOCKVAR. 0.59 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. (Refer to LUBRICATION &
MAINTENANCE/HOISTING - STANDARD PROCE-
DURE).
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. 81).
(4) Remove the two bolts attaching the proportion-
ing valve and bracket to the vehicle (Fig. 81).
(5) Slide the bracket out from under rear track bar
bracket. Lower the valve down enough to pull itsactuator rod 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 rod through the
axle bracket grommet and slide the proportioning
valve bracket under the rear track bar body bracket
(Fig. 81).
(2) Install the proportioning valve attaching bolts
(Fig. 81). 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.
81). 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.
(4) Bleed the brake system thoroughly to ensure
that all air has been expelled from the hydraulic sys-
tem. (Refer to 5 - BRAKES - BASE - STANDARD
PROCEDURE).
(5) Lower the vehicle to the ground.
(6) Road test the vehicle to verify proper operation
of the brake system.
ROTOR
DIAGNOSIS AND TESTING - BRAKE ROTOR
Any servicing of the rotor requires extreme care to
maintain the rotor within service tolerances to
ensure proper brake action.
Excessive runout or wobble in a rotor can increase
pedal travel due to piston knock-back. This increases
guide pin sleeve wear due to the tendency of the cal-
iper to follow the rotor wobble.
When diagnosing a brake noise or pulsation, the
machined disc braking surface should be checked and
inspected.
Fig. 81 PROPORTIONING VALVE MOUNTING
1 - LEFT REAR OUTLET TUBE
2 - RIGHT REAR OUTLET TUBE
3 - RIGHT REAR INLET TUBE
4 - MOUNTING BOLTS
5 - LEFT REAR INLET TUBE
RSBRAKES - BASE5-55
PROPORTIONING VALVE (Continued)