Dodge Durango (DN). Manual — part 245

(10) Install caliper bleed screw and bleed screw

cap if removed (Fig. 53).

WHEEL CYLINDER

DISASSEMBLY

(1) Remove push rods and boots (Fig. 54).
(2) Press pistons, cups and spring and expander

out of cylinder bore.

(3) Remove bleed screw.

ASSEMBLY

(1) Lubricate wheel cylinder bore, pistons, piston

cups and spring and expander with clean brake fluid.

(2) Install first piston in cylinder bore. Then

install first cup in bore and against piston. Be sure
lip of piston cup is facing inward (toward
spring and expander) and flat side is against
piston.

(3) Install

spring

and

expander

followed

by

remaining piston cup and piston.

(4) Install boots on each end of cylinder and insert

push rods in boots.

(5) Install cylinder bleed screw.

CLEANING AND INSPECTION

REAR DRUM BRAKE

CLEANING

Clean the individual brake components, including

the support plate and wheel cylinder exterior, with a
water dampened cloth or with brake cleaner. Do not
use any other cleaning agents. Remove light rust and
scale from the brake shoe contact pads on the sup-
port plate with fine sandpaper.

INSPECTION

As a general rule, riveted brake shoes should be

replaced when worn to within 0.78 mm (1/32 in.) of
the rivet heads. Bonded lining should be replaced
when worn to a thickness of 1.6 mm (1/16 in.).

Examine the lining contact pattern to determine if

the shoes are bent or the drum is tapered. The lining
should exhibit contact across its entire width. Shoes
exhibiting contact only on one side should be
replaced and the drum checked for runout or taper.

Inspect the adjuster screw assembly. Replace the

assembly if the star wheel or threads are damaged,
or the components are severely rusted or corroded.

Discard the brake springs and retainer components

if worn, distorted or collapsed. Also replace the
springs if a brake drag condition had occurred. Over-
heating will distort and weaken the springs.

Inspect the brake shoe contact pads on the support

plate, replace the support plate if any of the pads are
worn or rusted through. Also replace the plate if it is
bent or distorted (Fig. 55).

CALIPER

CLEANING

Clean the caliper components with clean brake

fluid or brake clean only. Wipe the caliper and piston
dry with lint free towels or use low pressure com-
pressed air.

Fig. 53 Installing Caliper Bleed Screw And Cap

1 – BLEED SCREW CAP
2 – BLEED SCREW

Fig. 54 Wheel Cylinder Components–Typical

1 – SPRING
2 – CYLINDER
3 – PISTON CUP
4 – BOOT
5 – PUSH ROD
6 – PISTON
7 – BLEED SCREW
8 – CUP EXPANDERS

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BRAKES

5 - 27

DISASSEMBLY AND ASSEMBLY (Continued)

CAUTION: Do not use gasoline, kerosene, paint
thinner, or similar solvents. These products may
leave a residue that could damage the piston and
seal.

INSPECTION

The piston is made from a phenolic resin (plastic

material) and should be smooth and clean.

The piston must be replaced if cracked or scored.

Do not attempt to restore a scored piston surface by
sanding or polishing.

CAUTION: If the caliper piston is replaced, install
the same type of piston in the caliper. Never inter-
change phenolic resin and steel caliper pistons.
The pistons, seals, seal grooves, caliper bore and
piston tolerances are different.

The bore can be lightly polished with a brake

hone to remove very minor surface imperfections
(Fig. 56). The caliper should be replaced if the bore is
severely corroded, rusted, scored, or if polishing
would increase bore diameter more than 0.025 mm
(0.001 inch).

WHEEL CYLINDER

CLEANING

Clean the cylinder and pistons with clean brake

fluid or brake cleaner only. Do not use any other
cleaning agents.

Dry the cylinder and pistons with compressed air.

Do not use rags or shop towels to dry the cylinder
components. Lint from cloth material will adhere to
the cylinder bores and pistons.

INSPECTION

Inspect the cylinder bore. Light discoloration and

dark stains in the bore are normal and will not
impair cylinder operation.

The cylinder bore can be lightly polished but only

with crocus cloth. Replace the cylinder if the bore is
scored, pitted or heavily corroded. Honing the bore to
restore the surface is not recommended.

Inspect the cylinder pistons. The piston surfaces

should be smooth and free of scratches, scoring and
corrosion. Replace the pistons if worn, scored, or cor-
roded. Do attempt to restore the surface by sanding
or polishing.

Discard the old piston cups and the spring and

expander. These parts are not reusable. The original
dust boots may be reused but only if they are in good
condition.

ADJUSTMENTS

REAR DRUM BRAKE

The rear drum brakes are equipped with a self-ad-

justing mechanism. Under normal circumstances, the
only time adjustment is required is when the shoes
are replaced, removed for access to other parts, or
when one or both drums are replaced.

Adjustment can be made with a standard brake

gauge or with adjusting tool. Adjustment is per-
formed with the complete brake assembly installed
on the backing plate.

ADJUSTMENT WITH BRAKE GAUGE

(1) Be sure parking brakes are fully released.
(2) Raise rear of vehicle and remove wheels and

brake drums.

Fig. 55 Shoe Contact Surfaces

1 – ANCHOR PIN
2 – SUPPORT PLATE
3 – SHOE CONTACT SURFACES

Fig. 56 Polishing Piston Bore

1 – SPECIAL HONE
2 – CALIPER
3 – PISTON BORE

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BRAKES

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CLEANING AND INSPECTION (Continued)

(3) Verify that left and right automatic adjuster

levers and cables are properly connected.

(4) Insert brake gauge in drum. Expand gauge

until gauge inner legs contact drum braking surface.
Then lock gauge in position (Fig. 57).

(5) Reverse gauge and install it on brake shoes.

Position gauge legs at shoe centers as shown (Fig.
58). If gauge does not fit (too loose/too tight), adjust
shoes.

(6) Pull shoe adjuster lever away from adjuster

screw star wheel.

(7) Turn adjuster screw star wheel (by hand) to

expand or retract brake shoes. Continue adjustment
until gauge outside legs are light drag-fit on shoes.

(8) Install brake drums and wheels and lower

vehicle.

(9) Drive vehicle and make one forward stop fol-

lowed by one reverse stop. Repeat procedure 8-10
times to operate automatic adjusters and equalize
adjustment.

NOTE: Bring vehicle to complete standstill at each
stop. Incomplete, rolling stops will not activate
automatic adjusters.

ADJUSTMENT WITH ADJUSTING TOOL

(1) Be sure parking brake lever is fully released.
(2) Raise vehicle so rear wheels can be rotated

freely.

(3) Remove plug from each access hole in brake

support plates.

(4) Loosen parking brake cable adjustment nut

until there is slack in front cable.

(5) Insert adjusting tool through support plate

access hole and engage tool in teeth of adjusting
screw star wheel (Fig. 59).

(6) Rotate adjuster screw star wheel (move tool

handle upward) until slight drag can be felt when
wheel is rotated.

(7) Push and hold adjuster lever away from star

wheel with thin screwdriver.

(8) Back off adjuster screw star wheel until brake

drag is eliminated.

Fig. 57 Adjusting Gauge On Drum

1 – BRAKE GAUGE
2 – BRAKE DRUM

Fig. 58 Adjusting Gauge On Brake Shoes

1 – BRAKE GAUGE
2 – BRAKE SHOES

Fig. 59 Brake Adjustment

1 – STAR WHEEL
2 – LEVER
3 – BRAKE SHOE WEB
4 – SCREWDRIVER
5 – ADJUSTING TOOL
6 – ADJUSTER SPRING

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BRAKES

5 - 29

ADJUSTMENTS (Continued)

(9) Repeat adjustment at opposite wheel. Be sure

adjustment is equal at both wheels.

(10) Install support plate access hole plugs.
(11) Adjust parking brake cable and lower vehicle.
(12) Drive vehicle and make one forward stop fol-

lowed by one reverse stop. Repeat procedure 8-10
times to operate automatic adjusters and equalize
adjustment.

NOTE: Bring vehicle to complete standstill at each
stop. Incomplete, rolling stops will not activate
automatic adjusters.

PARK BRAKE CABLE TENSIONER

NOTE: Tensioner

adjustment

is

only

necessary

when the tensioner, or a cable has been replaced or
disconnected for service. When adjustment is nec-
essary, perform adjustment only as described in the
following procedure. This is necessary to avoid
faulty park brake operation.

(1) Raise vehicle.
(2) Back off cable tensioner adjusting nut create

slack in cables.

(3) Remove

rear

wheel/tire

assemblies.

Then

remove brake drums.

(4) Verify brakes are in good condition and operat-

ing properly.

(5) Verify park brake cables operate freely and are

not binding, or seized.

(6) Check rear brake shoe adjustment with stan-

dard brake gauge.

(7) Install drums and verify that drums rotate

freely without drag.

(8) Install wheel/tire assemblies.
(9) Lower vehicle enough for access to park brake

foot pedal. Then fully apply park brakes.

NOTE: Leave park brakes applied until adjustment
is complete.

(10) Raise vehicle again.
(11) Mark tensioner rod 6.35 mm (1/4 in.) from

edge of tensioner if no mark is visible (Fig. 60).

NOTE: The rod is marked from the factory.

(12) Tighten adjusting nut on tensioner until the

1/4 inch mark is no longer visible.

CAUTION: Do not loosen, or tighten the tensioner
adjusting nut for any reason after completing
adjustment.

(13) Lower vehicle until rear wheels are 15-20 cm

(6-8 in.) off shop floor.

(14) Release park brake foot pedal and verify that

rear wheels rotate freely without drag. Then lower
vehicle.

SPECIFICATIONS

BRAKE FLUID

The brake fluid used in this vehicle must conform

to DOT 3 specifications and SAE J1703 standards.
No other type of brake fluid is recommended or
approved for usage in the vehicle brake system. Use
only Mopar brake fluid or an 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.

Fig. 60 Adjustment Mark On Cable Tensioner Rod

1 – CABLE CONNECTOR
2 – ADJUSTER NUT
3 – 6.35MM (1/4 IN.)

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BRAKES

DN

ADJUSTMENTS (Continued)