Installation - Proportioning Valve (Height Sensing); Rotor; Diagnosis And Testing - Brake Rotor - Chrysler Dodge Caravan 2002 Manual

RS
PROPORTIONING VALVE (Continued)
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. 92).
(2) Install the proportioning valve attaching bolts
(Fig. 92). 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.
92). 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.
BRAKING SURFACE INSPECTION
Light braking surface scoring and wear is accept-
able. If heavy scoring or warping is evident, the rotor
must be refaced or replaced. (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/ROTORS
DARD PROCEDURE).
Excessive wear and scoring of the rotor can cause
improper lining contact on the rotor's braking sur-
face. If the ridges on the rotor are not removed before
new brake shoes are installed, improper wear of the
shoes will result.
If a vehicle has not been driven for a period of time,
the rotor's braking surface will rust in the areas not
covered by the brake shoes at that time. Once the
vehicle is driven, noise and chatter from the disc
brakes can result when the brakes are applied.
Some discoloration or wear of the rotor surface is
normal and does not require resurfacing when lin-
ings are replaced. If cracks or burned spots are evi-
dent, the rotor must be replaced.
ROTOR MINIMUM THICKNESS
Measure rotor thickness at the center of the brake
shoe contact surface. Replace the rotor if it is worn
below minimum thickness or if machining the rotor
will cause its thickness to fall below specifications.
CAUTION: Do not machine the rotor if it will cause
the rotor to fall below minimum thickness.
Minimum thickness specifications are cast on the
rotor's unmachined surface (Fig. 93). Limits can also
be found in this section's specification table. (Refer to
5 - BRAKES/HYDRAULIC/MECHANICAL/ROTOR -
SPECIFICATIONS)
Fig. 93 Minimum Brake Rotor Thickness Markings
1 - ROTOR MINIMUM THICKNESS MARKING
2 - ROTOR
ROTOR THICKNESS VARIATION
Thickness variation in a rotor's braking surface
can result in pedal pulsation, chatter and surge. This
can also be caused by excessive runout in the rotor or
the hub.
Rotor thickness variation measurements should be
made in conjunction with measuring runout. Mea-
- STAN-
sure thickness of the brake rotor at 12 equal points
around the rotor braking surface with a micrometer
at a radius approximately 25 mm (1 inch) from edge
of rotor (Fig. 94). If thickness measurements vary
beyond the specification listed in the specifaction
table (Refer to 5 - BRAKES/HYDRAULIC/MECHAN-
ICAL/ROTOR - SPECIFICATIONS), the rotor should
be refaced or replaced. (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTORS
PROCEDURE).
BRAKES - BASE
(Typical)
- STANDARD
5 - 59