1996 CHRYSLER VOYAGER Service Manual

both the rotor and one wheel stud on the high side of
the runout. This will ensure that the original location
of the rotor in relation to the hub can be retained
(Fig. 14). Remove rotor from hub.
Thoroughly clean the front surface of the front
hub. Then install Dial Indicator, Special Tool C-3339
and Mounting Adaptor, Special Tool SP-1910 on
steering knuckle. Position stem so it contacts hub
face near outer diameter. Care must be taken to posi-
tion stem outside the stud circle but inside the cham-
fer on the hub face (Fig. 15).Clean hub surface
before checking.
Lateral runout should not exceed 0.08 mm (0.003
inch). If runout exceeds this specification, the hub
must be replaced. See Suspension Group 2. If lateral
runout of the hub does not exceed this specification,
install rotor on hub with chalk marks two wheel
studs apart (Fig. 16). Tighten nuts in the properse-
quence and torque to specification. Finally, check lat-eral runout of rotor to see if lateral runout is now
within specification.
If lateral runout is not within specification, install
a new rotor or reface rotor, being careful to remove
as little rotor material as possible from each side of
rotor. Remove equal amounts from each side of rotor.
Do not reduce thickness below minimum thickness
marking cast into the un-machined surface (Fig. 17)
of the rotor .
Thickness variation measurements of the rotor
should be made in conjunction with the lateral
runout measurements. Measure the thickness of the
rotor at 12 circumferentially equal points with a
Fig. 16 Indexing Rotor And Wheel Stud
Fig. 13 Checking Brake Rotor For Runout
Fig. 14 Marking Rotor And Wheel Stud
Fig. 15 Checking Disc Brake Rotor For Runout
NSBRAKES 5 - 15
DIAGNOSIS AND TESTING (Continued)

micrometer at a radius approximately 25.4 mm (1
inch) from outer edge of rotor (Fig. 18). If thickness
measurements vary by more than 0.013 mm (0.0005
inch), rotor should be removed and resurfaced, or a
new rotor installed. If cracks or burned spots are evi-
dent, rotor must be replaced.
Light scoring and/or wear is acceptable. If heavy
scoring or warping is evident, the rotor must be
refinished or replaced (See Refinishing/RefacingRotor). If cracks are evident in the rotor, replace the
rotor.
PROPORTIONING VALVES
FIXED PROPORTIONING VALVE TEST
PROCEDURE
On a vehicle equipped with ABS, premature or
excessive rear wheel ABS cycling may be an indica-
tion that the brake fluid pressure to the rear brakes
is above the desired output.
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. The vehicles brake system is
not balanced for after market brake shoe
assembly lining material.
If brake shoe assembly lining material is of satis-
factory condition, and of the correct material specifi-
cation, check for proper proportioning valve function
using the following procedure.
(1) Road test vehicle to be sure the vehicle is truly
exhibiting a condition of excessive rear wheel ABS
cycling. Since ABS cycles both rear brakes together
both proportioning valves of the assembly(Fig.
19) must be tested. Use the following procedure to
test the proportioning valve.
(2) Remove one of the chassis brake lines (Fig. 19)
coming from the ABS modulator, at
(3) the proportioning valve assembly. Remove the
hydraulic brake line going to one of the rear wheels
of the vehicle from the proportioning valve (Fig. 19)
Fig. 17 Minimum Rotor Thickness Markings
Fig. 18 Checking Rotor For Thickness Variation
Fig. 19 Rear Brake Proportioning Valve And Brake
Tube Locations
5 - 16 BRAKESNS
DIAGNOSIS AND TESTING (Continued)

(4) Remove the 2 bolts (Fig. 19) attaching the pro-
portioning valve to the frame rail.
CAUTION: When lowering the proportioning valve,
care must be taken not to kink any of the chassis
brake lines.
(5) Carefully lower the proportioning valve for
clearance to install the proportioning valve test fit-
tings.
(6) Install the required fitting from Pressure Test
Fittings, Special Tool 6833 (Fig. 20) into the inlet
port of the proportioning valve assembly, from which
the chassis brake line was removed. Install the
removed chassis brake line into the Pressure Test
Fitting (Fig. 20). Install the required fitting from
Pressure Test Fittings, Special Tool 6833 into the
required outlet port of the proportioning valve.
Install the required fitting from Pressure Test Fit-
tings, Special Tool 6833 into the required outlet port
of the proportioning valve (Fig. 20). Then install the
removed chassis brake line into the Pressure Test
Fitting (Fig. 20).
(7) Install a pressure gauge from Gauge Set, Spe-
cial Tool C-4007-A into each pressure test fitting (Fig.
21). Bleed air out of hose from pressure test fittings
to pressure gauges, at the pressure gauges (Fig. 21).
Then bleed air out of the brake line being tested, at
that rear wheel cylinder.
(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.(9) Repeat steps 2 through 7 for the other propor-
tioning valve of the assembly.
CAUTION: When mounting the original or a
replacement proportion valve on the frame rail of
the vehicle install the mounting bolts in only the
two forward holes of the mounting bracket (Fig. 19).
HEIGHT SENSING PROPORTIONING VALVE
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.
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 an
incorrectly adjusted proportioning valve actuator
assembly, or contaminated front or rear brake lin-
ings.
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
Fig. 20 Proportioning Valve Test Fitting Installation
Fig. 21 Pressure Gauges Installed On Pressure Test
Fittings
NSBRAKES 5 - 17
DIAGNOSIS AND TESTING (Continued)

shoe assemblies meeting the OEM lining mate-
rial specification. The vehicles brake system is
not balanced for after market brake shoe
assembly lining material.
If both front and rear brakes check OK, proceed to
verify that the actuator assembly for the height sens-
ing proportioning valve is adjusted correctly. See
Height Sensing Proportioning Valve in the Adjust-
ment Section in this group of the service manual for
the adjustment procedure. If the proportioning valve
is adjusted correctly, proceed with the test procedure
for the height sensing proportioning valve as follows:
(1) Remove the actuator assembly adjustment nut
(Fig. 22). Remove the actuator assembly from the
lever on the height sensing proportioning valve.
(2) Remove the chassis brake tube coming from
the junction block from the front of the height sens-
ing proportioning valve (Fig. 23). Remove the chassis
brake tube going to the rear brakes from the back of
the height sensing proportioning valve (Fig. 23).(3) Install the required fittings from Pressure Test
Fittings, Special Tool 6833 (Fig. 24) into the inlet
port of the proportioning valve assembly, from which
the chassis brake line was removed. Install the
removed chassis brake line into the Pressure Test
Fitting (Fig. 24). Install the required fitting from
Pressure Test Fittings, Special Tool 6833 into the
required outlet port of the proportioning valve.
Install the required fitting from Pressure Test Fit-
tings, Special Tool 6833 into the required outlet port
of the proportioning valve (Fig. 24). Then install the
removed chassis brake line into the Pressure Test
Fitting (Fig. 20).
(4) Install a pressure gauge from Gauge Set, Spe-
cial Tool C-4007-A into each pressure test fitting (Fig.
25). Bleed air out of hose from pressure test fittings
to pressure gauges, at the pressure gauges (Fig. 25).
Then bleed air out of the brake line being tested, at
that rear wheel cylinder.
Fig. 22 Actuator Assembly Adjustment Nut
Fig. 23 Brake Tube Connections To Proportioning
Valve
Fig. 24 Proportioning Valve Test Fitting Installation
Fig. 25 Pressure Gauges Installed On Pressure Test
Fittings
5 - 18 BRAKESNS
DIAGNOSIS AND TESTING (Continued)