1998 DODGE RAM 1500 system

FLUID RESERVOIR
REMOVAL.............................23
INSTALLATION.........................24
BRAKE JUNCTION BLOCK
REMOVAL.............................24
INSTALLATION.........................24
MASTER CYLINDER
DESCRIPTION.........................24
OPERATION...........................25
DIAGNOSIS AND TESTING - MASTER
CYLINDER/POWER BOOSTER...........25
STANDARD PROCEDURE - MASTER
CYLINDER BLEEDING..................26
REMOVAL
REMOVAL - ALL EXCEPT HYDROBOOST . . . 26
REMOVAL - HYDROBOOST.............26
INSTALLATION
INSTALLATION - ALL EXCEPT
HYDROBOOST.......................27
INSTALLATION - HYDROBOOST..........27
PEDAL
DESCRIPTION.........................28
OPERATION...........................28
REMOVAL.............................28
INSTALLATION.........................28
POWER BRAKE BOOSTER
DESCRIPTION.........................29
OPERATION...........................29
REMOVAL.............................29
INSTALLATION.........................29
HYDRO-BOOST BRAKE BOOSTER
DIAGNOSIS AND TESTING - HYDRAULIC
BOOSTER...........................30
STANDARD PROCEDURE - BLEEDING......31
REMOVAL.............................31
INSTALLATION.........................32
ROTORS
DIAGNOSIS AND TESTING
DISC BRAKE ROTOR..................32
REMOVAL
REMOVAL - FRONT....................33
REMOVAL - REAR.....................34REMOVAL - REAR DUAL WHEELS........34
INSTALLATION
INSTALLATION - FRONT................34
INSTALLATION - REAR.................34
INSTALLATION - REAR DUAL WHEELS....35
SUPPORT PLATE
REMOVAL.............................35
INSTALLATION.........................36
PARKING BRAKE
DESCRIPTION.........................36
OPERATION...........................36
CABLES
REMOVAL
REMOVAL - FRONT PARKING BRAKE
CABLE..............................36
REMOVAL - REAR PARK BRAKE CABLE . . . 37
REMOVAL - RIGHT REAR CABLE.........37
REMOVAL - LEFT REAR CABLE..........38
INSTALLATION
INSTALLATION - FRONT PARKING BRAKE
CABLE..............................38
INSTALLATION - REAR PARK BRAKE
CABLE..............................38
INSTALLATION - RIGHT REAR CABLE.....38
INSTALLATION - LEFT REAR CABLE......39
SHOES
REMOVAL.............................39
CLEANING - REAR DRUM IN HAT BRAKE....39
INSPECTION - REAR DRUM IN HAT BRAKE . . 39
INSTALLATION.........................40
ADJUSTMENTS
ADJUSTMENT - PARKING BRAKE SHOES . . 41
ADJUSTMENT - WITH ADJUSTING TOOL . . . 42
PEDAL
REMOVAL.............................42
INSTALLATION.........................42
CABLE TENSIONER
ADJUSTMENTS
ADJUSTMENT........................43
RELEASE HANDLE
REMOVAL.............................44
INSTALLATION.........................44
BRAKES - BASE
DIAGNOSIS AND TESTING - BASE BRAKE
SYSTEM
Base brake components consist of the brake pads,
calipers, brake drum in hat rotor in the rear, rotors,
brake lines, master cylinder, booster, and parking
brake components.
Brake diagnosis involves determining if the prob-
lem is related to a mechanical, hydraulic, or vacuum
operated component.
The first diagnosis step is the preliminary check.
PRELIMINARY BRAKE CHECK
(1) Check condition of tires and wheels. Damaged
wheels and worn, damaged, or underinflated tires
can cause pull, shudder, vibration, and a condition
similar to grab.
(2) If complaint was based on noise when braking,
check suspension components. Jounce front and rear
of vehicle and listen for noise that might be caused
by loose, worn or damaged suspension or steering
components.
(3) Inspect brake fluid level and condition. Note
that the brake reservoir fluid level will decrease in
proportion to normal lining wear.Also note that
brake fluid tends to darken over time. This is
5 - 2 BRAKES - BASEDR

normal and should not be mistaken for contam-
ination.
(a) If fluid level is abnormally low, look for evi-
dence of leaks at calipers, wheel cylinders, brake
lines, and master cylinder.
(b) If fluid appears contaminated, drain out a
sample to examine. System will have to be flushed
if fluid is separated into layers, or contains a sub-
stance other than brake fluid. The system seals
and cups will also have to be replaced after flush-
ing. Use clean brake fluid to flush the system.
(4) Check parking brake operation. Verify free
movement and full release of cables and pedal. Also
note if vehicle was being operated with parking
brake partially applied.
(5) Check brake pedal operation. Verify that pedal
does not bind and has adequate free play. If pedal
lacks free play, check pedal and power booster for
being loose or for bind condition. Do not road test
until condition is corrected.
(6) Check booster vacuum check valve and hose.
(7) If components checked appear OK, road test
the vehicle.
ROAD TESTING
(1) If complaint involved low brake pedal, pump
pedal and note if it comes back up to normal height.
(2) Check brake pedal response with transmission
in Neutral and engine running. Pedal should remain
firm under constant foot pressure.
(3) During road test, make normal and firm brake
stops in 25-40 mph range. Note faulty brake opera-
tion such as low pedal, hard pedal, fade, pedal pulsa-
tion, pull, grab, drag, noise, etc.
(4) Attempt to stop the vehicle with the parking
brake only and note grab, drag, noise, etc.
PEDAL FALLS AWAY
A brake pedal that falls away under steady foot
pressure is generally the result of a system leak or
fluid contamination. The leak point could be at a
brake line, fitting, hose, or caliper/wheel cylinder. If
leakage is severe, fluid will be evident at or around
the leaking component.
Internal leakage (seal by-pass) in the master cylin-
der caused by worn or damaged piston cups, may
also be the problem cause.
An internal leak in the ABS or RWAL system may
also be the problem with no physical evidence.
LOW PEDAL
If a low pedal is experienced, pump the pedal sev-
eral times. If the pedal comes back up worn linings,
rotors, drums, or rear brakes out of adjustment are
the most likely causes. The proper course of action isto inspect and replace all worn component and make
the proper adjustments.
SPONGY PEDAL
A spongy pedal is most often caused by air in the
system. However, thin brake drums or substandard
brake lines and hoses can also cause a spongy pedal.
The proper course of action is to bleed the system,
and replace thin drums and substandard quality
brake hoses if suspected.
HARD PEDAL OR HIGH PEDAL EFFORT
A hard pedal or high pedal effort may be due to
lining that is water soaked, contaminated, glazed, or
badly worn. The power booster or check valve or a
vacuum hose could also be faulty.
PEDAL PULSATION
Pedal pulsation is caused by components that are
loose, or beyond tolerance limits.
The primary cause of pulsation are disc brake
rotors with excessive lateral runout or thickness vari-
ation, or out of round brake drums. Other causes are
loose wheel bearings or calipers and worn, damaged
tires.
NOTE: Some pedal pulsation may be felt during
ABS activation.
BRAKE DRAG
Brake drag occurs when the lining is in constant
contact with the rotor or drum. Drag can occur at one
wheel, all wheels, fronts only, or rears only.
Drag is a product of incomplete brake shoe release.
Drag can be minor or severe enough to overheat the
linings, rotors and drums.
Minor drag will usually cause slight surface char-
ring of the lining. It can also generate hard spots in
rotors and drums from the overheat-cool down pro-
cess. In most cases, the rotors, drums, wheels and
tires are quite warm to the touch after the vehicle is
stopped.
Severe drag can char the brake lining all the way
through. It can also distort and score rotors and
drums to the point of replacement. The wheels, tires
and brake components will be extremely hot. In
severe cases, the lining may generate smoke as it
chars from overheating.
Common causes of brake drag are:
²Seized or improperly adjusted parking brake
cables.
²Loose/worn wheel bearing.
²Seized caliper or wheel cylinder piston.
²Caliper binding on corroded bushings or rusted
slide surfaces.
²Loose caliper mounting.
DRBRAKES - BASE 5 - 3
BRAKES - BASE (Continued)

of chatter are out-of-tolerance rotors, brake lining not
securely attached to the shoes, loose wheel bearings
and contaminated brake lining.
THUMP/CLUNK NOISE
Thumping or clunk noises during braking are fre-
quentlynotcaused by brake components. In many
cases, such noises are caused by loose or damaged
steering, suspension, or engine components. However,
calipers that bind on the slide surfaces can generate
a thump or clunk noise.
STANDARD PROCEDURE
STANDARD PROCEDURE - MANUAL BLEEDING
Use Mopar brake fluid, or an equivalent quality
fluid meeting SAE J1703-F and DOT 3 standards
only. Use fresh, clean fluid from a sealed container at
all times.
(1) Remove reservoir filler caps and fill reservoir.
(2) If calipers were overhauled, open all caliper
bleed screws. Then close each bleed screw as fluid
starts to drip from it. Top off master cylinder reser-
voir once more before proceeding.
(3) Attach one end of bleed hose to bleed screw
and insert opposite end in glass container partially
filled with brake fluid (Fig. 1). Be sure end of bleed
hose is immersed in fluid.
NOTE: Bleed procedure should be in this order (1)
Right rear (2) Left rear (3) Right front (4) Left front.(4) Open up bleeder, then have a helper press
down the brake pedal. Once the pedal is down close
the bleeder. Repeat bleeding until fluid stream is
clear and free of bubbles. Then move to the next
wheel.
(5) Before moving the vehicle verify the pedal is
firm and not mushy.
(6) Top off the brake fluid and install the reservoir
cap.
STANDARD PROCEDURE - PRESSURE
BLEEDING
Use Mopar brake fluid, or an equivalent quality
fluid meeting SAE J1703-F and DOT 3 standards
only. Use fresh, clean fluid from a sealed container at
all times.
Follow the manufacturers instructions carefully
when using pressure equipment. Do not exceed the
tank manufacturers pressure recommendations. Gen-
erally, a tank pressure of 15-20 psi is sufficient for
bleeding.
Fill the bleeder tank with recommended fluid and
purge air from the tank lines before bleeding.
Do not pressure bleed without a proper master cyl-
inder adapter. The wrong adapter can lead to leak-
age, or drawing air back into the system.
SPECIAL TOOLS
BASE BRAKES
Fig. 1 Bleed Hose Setup
1 - BLEED HOSE
2 - FLUID CONTAINER PARTIALLY FILLED WITH FLUID
INSTALLER, BRAKE CALIPER DUST BOOT C-4340
INSTALLER, BRAKE CALIPER DUST BOOT
C-3716-A
DRBRAKES - BASE 5 - 5
BRAKES - BASE (Continued)

ADJUSTABLE PEDAL SWITCH
REMOVAL
(1) Remove the lower drivers side bezel (Refer to
23 - BODY/INSTRUMENT PANEL/INSTRUMENT
PANEL DR SIDE BEZEL - REMOVAL).
(2) Disconnect the electrical connector from the
adjustable pedal switch.
(3) Remove the switch from the lower drivers side
bezel by squeezing the retaining clips together and
pushing the switch outwards (Fig. 2).
INSTALLATION
(1) Install the switch to the lower drivers side
bezel by pushing the switch inwards seating the
retaining clips to the lower drivers side bezel.
(2) Reconnect the electrical connector to the
adjustable pedal switch.
(3) Install the lower drivers side bezel (Fig. 2)
(Refer to 23 - BODY/INSTRUMENT PANEL/IN-
STRUMENT PANEL DR SIDE BEZEL - INSTALLA-
TION).
ADJUSTABLE PEDAL MOTOR
DESCRIPTION
The Adjustable Pedals System (APS) is designed to
enable the fore and aft repositioning of the brake and
accelerator pedals. This results in improved ergonom-
ics in relation to the steering wheel for taller and
shorter drivers. Being able to adjust the pedal posi-
tions also allows the driver to set steering wheel tilt
and seat position to the most comfortable position.
The position of the brake and accelerator pedals can
be adjusted without compromising safety or comfort
in actuating the pedals.
Change of pedal position is accomplished by means
of a motor driven screw. Operating the adjustable
pedal switch activates the pedal drive motor (Fig. 3).
The pedal drive motor turns a screw that changes
the position of the brake and accelerator pedals. The
pedal can be moved rearward (closer to the driver) or
forward (away from driver). The brake pedal is
moved on its drive screw to a position where the
driver feels most comfortable.
The accelerator pedal is moved at the same time
and the same distance as the brake pedal.
Neither the pedal drive motor (Fig. 3) nor drive
mechanism are subject to the mechanical stress of
brake or accelerator application.
²SYSTEM FEATURES:
²Range of Adjustment: The pedals may be
adjusted up to 3 in. (75 mm)
²Pedal Adjustment Speed: 0.5 in./sec (12.5
mm/sec)
HANDLE C-4171
CAP, MASTER CYLINDER PRESSURE BLEED 6921
GAUGE, BRAKE SAFE-SET C-3919
Fig. 2 LOWER DRIVERS SIDE BEZEL
1 - SCREWS (2)
2 - ADJUSTABLE PEDAL SWITCH (if equipped)
3 - PEDAL SWITCH ELECTRICAL CONNECTOR
4 - BEZEL
5 - 6 BRAKES - BASEDR
BRAKES - BASE (Continued)

(9) Tighten tool handle until plug gauge is
squarely seated on jaws of flaring tool. This will start
the inverted flare.
(10) Remove the plug gauge and complete the
inverted flare.
STANDARD PROCEDURE - ISO FLARING
A preformed metal brake tube is recommended and
preferred for all repairs. However, double-wall steel
tube can be used for emergency repair when factory
replacement parts are not readily available.
To make a ISO flare use an ISO flaring tool kit.
(1) Cut off damaged tube with Tubing Cutter.
(2) Remove any burrs from the inside of the tube.
(3) Install tube nut on the tube.
(4) Position the tube in the flaring tool flush with
the top of the tool bar (Fig. 6). Then tighten the tool
bar on the tube.
(5) Install the correct size adaptor on the flaring
tool yoke screw.
(6) Lubricate the adaptor.
(7) Align the adaptor and yoke screw over the tube
(Fig. 6).
(8) Turn the yoke screw in until the adaptor is
squarely seated on the tool bar.
REMOVAL
REMOVAL - REAR BRAKE HOSE
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support the vehicle.(3) Remove the brake line from the hose at the
frame (Fig. 7).
(4) Remove the brake hose clip at the top of the
hose located at the frame (Fig. 7).
(5) Remove the vent tube (Fig. 8).
(6) Remove the two brake lines at the bottom of
the hose located at the axle (Fig. 8).
Fig. 5 Inverted Flare Tools
Fig. 6 ISO Flaring
1 - ADAPTER
2 - LUBRICATE HERE
3 - PILOT
4 - FLUSH WITH BAR
5 - TUBING
6 - BAR ASSEMBLY
Fig. 7 BRAKE LINE CLIP
1 - BRAKE HOSE
2 - CLIP
3 - BRAKE LINE
DRBRAKES - BASE 5 - 11
BRAKE LINES (Continued)

(7) Remove the mounting bolt for the brake hose
at the axle (Fig. 8).
(8) Remove the hose.
REMOVAL - REAR TUBE / HOSE ASSEMBLY
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support the vehicle.
(3) Remove the brake line located at the axle.
(4) Remove the mounting bolt for the brake hose
at the axle (Fig. 9).
(5) Remove the banjo bolt at the caliper (Fig. 9).
(6) Remove the hose.
REMOVAL - FRONT HOSE
(1) Install a prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support vehicle.
(3) Remove the tire and wheel assembly.
(4) Remove the brake hose from the brake line
located at the frame (Fig. 10).
(5) Remove the brake hose banjo bolt at the caliper
(Fig. 10).
(6) Remove the mounting bolt securing the brake
hose to the frame and remove the wheel speed sensor
wire from the brake hose (Fig. 10).
(7) Remove the hose.
INSTALLATION
INSTALLATION - REAR BRAKE HOSE
(1) Install the hose.
(2) Install the mounting bolt for the brake hose at
the axle (Fig. 8).
(3) Install the two brake lines at the bottom of the
hose located at the axle (Fig. 8).
(4) Install the vent tube (Fig. 8).
(5) Install the brake hose clip at the top of the
hose located at the frame (Fig. 7).
(6) Install the brake line to the hose at the frame
(Fig. 7).
(7) Lower the vehicle and remove the support.
(8) Remove the prop rod.
(9) Bleed the brake system (Refer to 5 - BRAKES -
STANDARD PROCEDURE).
Fig. 8 REAR HOSE
1 - BRAKE HOSE
2 - VENT HOSE
3 - BRAKE LINES
Fig. 9 BRAKE LINE WITH RUBBER HOSE
1 - BANJO BOLT
2 - MOUNTING BOLT
3 - REAR TUBE / HOSE ASSEMBLY
Fig. 10 BRAKE HOSE MOUNTED PASSENGER SIDE
1 - MOUNTING BOLT
2 - BRAKE HOSE
3 - BANJO BOLT
4 - WHEEL SPEED SENSOR WIRE
5 - 12 BRAKES - BASEDR
BRAKE LINES (Continued)

INSTALLATION - REAR TUBE / HOSE
ASSEMBLY
(1) Install the hose.
(2) Install the banjo bolt at the caliper (Fig. 9) and
tighten fitting bolt to 27 N´m (245 in. lbs.).
(3) Install the mounting bolt for the brake hose at
the axle (Fig. 9).
(4) Install the brake line located at the axle.
(5) Lower the vehicle and remove the support.
(6) Remove the prop rod.
(7) Bleed the brake system (Refer to 5 - BRAKES -
STANDARD PROCEDURE).
INSTALLATION - FRONT BRAKE HOSE
(1) Install the hose.
(2) Install the mounting bolt for the brake hose at
the frame (Fig. 11).
(3) Install the brake hose banjo bolt at the caliper
(Fig. 10).
(4) Reinstall the wheel speed sensor wire to the
brake hose (Fig. 10).
(5) Remove the support and lower the vehicle.
(6) Remove the prop rod from the brake pedal.
(7) Bleed the brake system (Refer to 5 - BRAKES -
STANDARD PROCEDURE).
BRAKE PADS/SHOES
REMOVAL
REMOVAL - FRONT
(1) Raise and support vehicle.
(2) Remove the wheel and tire assemblies.(3) Compress the caliper.
(4) Remove the caliper, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- REMOVAL).
(5) Remove the caliper by tilting the top up and off
the caliper adapter (Fig. 12).
NOTE: Do not allow brake hose to support caliper
assembly.
(6) Support and hang the caliper. (Fig. 13)
(7) Remove the inboard brake shoe from the cali-
per adapter (Fig. 14).
Fig. 11 BRAKE HOSE MOUNT DRIVERS SIDE
1 - MOUNTING BOLT
2 - WHEEL SPEED SENSOR WIRE
3 - BRAKE HOSE
Fig. 12 Caliper
1 - CALIPER
2 - CALIPER ADAPTER
Fig. 13 DISC BRAKE CALIPER - FRONT
1 - STEERING KNUCKLE
2 - DISC BRAKE CALIPER
3 - CALIPER MOUNTING ADAPTER
4 - DISC BRAKE ROTOR
DRBRAKES - BASE 5 - 13
BRAKE LINES (Continued)

rotor. At the same time, fluid pressure within the pis-
ton bore forces the caliper to slide inward on the
mounting bolts. This action brings the outboard
brake pad lining into contact with the outer surface
of the disc brake rotor.
In summary, fluid pressure acting simultaneously
on both piston and caliper, produces a strong clamp-
ing action. When sufficient force is applied, friction
will attempt to stop the rotors from turning and
bring the vehicle to a stop.
Application and release of the brake pedal gener-
ates only a very slight movement of the caliper and
piston. Upon release of the pedal, the caliper and pis-
ton return to a rest position. The brake pads do not
retract an appreciable distance from the rotor. In
fact, clearance is usually at, or close to zero. The rea-
sons for this are to keep road debris from getting
between the rotor and lining and in wiping the rotor
surface clear each revolution.
The caliper piston seal controls the amount of pis-
ton extension needed to compensate for normal lining
wear.
During brake application, the seal is deflected out-
ward by fluid pressure and piston movement (Fig.
25). When the brakes (and fluid pressure) are
released, the seal relaxes and retracts the piston.
The amount of piston retraction is determined by
the amount of seal deflection. Generally the amountis just enough to maintain contact between the pis-
ton and inboard brake pad.
REMOVAL
REMOVAL - FRONT
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose will result. Provide a suitable support to hang
the caliper securely.
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support the vehicle.
(3) Remove the tire and wheel assembly.
(4) Compress the disc brake caliper.
(5) Remove the banjo bolt and discard the copper
washer.
(6) Remove the caliper slide bolts.
(7) Remove the disc brake caliper (Fig. 26) or (Fig.
27).
REMOVAL - REAR
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose will result. Provide a suitable support to hang
the caliper securely.
(1) Install prop rod on the brake pedal to keep
pressure on the brake system.
(2) Raise and support vehicle.
(3) Remove the wheel and tire assembly.
(4) Drain small amount of fluid from master cylin-
der brake reservoir with suction gun.
(5) Remove the brake hose banjo bolt and discard
the copper washers if replacing caliper (Fig. 28).
Fig. 24 Brake Caliper Operation
1 - CALIPER
2 - PISTON
3 - PISTON BORE
4 - SEAL
5 - INBOARD SHOE
6 - OUTBOARD SHOE
Fig. 25 Lining Wear Compensation By Piston Seal
1 - PISTON
2 - CYLINDER BORE
3 - PISTON SEAL BRAKE PRESSURE OFF
4 - CALIPER HOUSING
5 - DUST BOOT
6 - PISTON SEAL BRAKE PRESSURE ON
DRBRAKES - BASE 5 - 17
DISC BRAKE CALIPERS (Continued)