1998 DODGE RAM 1500 Fluid

(21) Install differential in housing and verify gear
backlash and gear contact pattern.
(22) Measure final rotating torque with an inch
pound torque wrench. The final pinion rotating
torque plus differential case bearing preload is:
²New Bearings:3.4-5.6 N´m (30-50 in. lbs.)
²Original Bearings:2.8-5.1 N´m (25-45 in. lbs.)
(23) Install axle shafts.(24) Install the propeller shaft with the reference
marks aligned.
(25) Install differential cover with gasket and
tighten bolts to 40 N´m (30 ft. lbs.).
(26) Fill differential with fluid and tighten fill plug
to 32 N´m (24 ft. lbs.).
DRREAR AXLE - 11 1/2 AA 3 - 167
PINION GEAR/RING GEAR/TONE RING (Continued)

BRAKES
TABLE OF CONTENTS
page page
BRAKES - BASE........................... 1BRAKES - ABS........................... 45
BRAKES - BASE
TABLE OF CONTENTS
page page
BRAKES - BASE
DIAGNOSIS AND TESTING - BASE BRAKE
SYSTEM.............................2
STANDARD PROCEDURE
STANDARD PROCEDURE - MANUAL
BLEEDING............................5
STANDARD PROCEDURE - PRESSURE
BLEEDING............................5
SPECIAL TOOLS
BASE BRAKES........................5
ADJUSTABLE PEDAL SWITCH
REMOVAL.............................6
INSTALLATION..........................6
ADJUSTABLE PEDAL MOTOR
DESCRIPTION..........................6
REMOVAL.............................7
INSTALLATION..........................7
HYDRAULIC/MECHANICAL
SPECIFICATIONS
SPECIFICATIONS - TORQUE CHART.......8
BASE BRAKE........................10
BRAKE LINES
STANDARD PROCEDURE
STANDARD PROCEDURE - DOUBLE
INVERTED FLARING...................10
STANDARD PROCEDURE - ISO FLARING . . 11
REMOVAL
REMOVAL - REAR BRAKE HOSE.........11
REMOVAL - REAR TUBE / HOSE
ASSEMBLY..........................12
REMOVAL - FRONT HOSE..............12
INSTALLATION
INSTALLATION - REAR BRAKE HOSE......12
INSTALLATION - REAR TUBE / HOSE
ASSEMBLY..........................13
INSTALLATION - FRONT BRAKE HOSE....13BRAKE PADS/SHOES
REMOVAL
REMOVAL - FRONT....................13
REMOVAL - REAR.....................14
INSTALLATION
INSTALLATION - FRONT................16
INSTALLATION - REAR.................16
DISC BRAKE CALIPERS
DESCRIPTION.........................16
OPERATION...........................16
REMOVAL
REMOVAL - FRONT....................17
REMOVAL - REAR.....................17
DISASSEMBLY.........................18
INSPECTION..........................19
ASSEMBLY............................20
INSTALLATION
INSTALLATION - FRONT................21
INSTALLATION - REAR.................21
DISC BRAKE CALIPER ADAPTER
REMOVAL
REMOVAL - FRONT....................21
REMOVAL - REAR.....................21
INSTALLATION
INSTALLATION - FRONT................22
INSTALLATION - REAR.................22
DISC BRAKE CALIPER ADAPTER MOUNT
REMOVAL - REAR......................22
INSTALLATION.........................22
FLUID
DIAGNOSIS AND TESTING - BRAKE FLUID
CONTAMINATION.....................23
STANDARD PROCEDURE - BRAKE FLUID
LEVEL..............................23
SPECIFICATIONS
BRAKE FLUID........................23
DRBRAKES 5 - 1

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)

²Drum brake shoes binding on worn/damaged
support plates.
²Mis-assembled components.
²Long booster output rod.
If brake drag occurs at all wheels, the problem
may be related to a blocked master cylinder return
port, or faulty power booster (binds-does not release).
BRAKE FADE
Brake fade is usually a product of overheating
caused by brake drag. However, brake overheating
and resulting fade can also be caused by riding the
brake pedal, making repeated high deceleration stops
in a short time span, or constant braking on steep
mountain roads. Refer to the Brake Drag information
in this section for causes.
BRAKE PULL
Front brake pull condition could result from:
²Contaminated lining in one caliper
²Seized caliper piston
²Binding caliper
²Loose caliper
²Rusty caliper slide surfaces
²Improper brake pads
²Damaged rotor
A worn, damaged wheel bearing or suspension
component are further causes of pull. A damaged
front tire (bruised, ply separation) can also cause
pull.
A common and frequently misdiagnosed pull condi-
tion is where direction of pull changes after a few
stops. The cause is a combination of brake drag fol-
lowed by fade at one of the brake units.
As the dragging brake overheats, efficiency is so
reduced that fade occurs. Since the opposite brake
unit is still functioning normally, its braking effect is
magnified. This causes pull to switch direction in
favor of the normally functioning brake unit.
An additional point when diagnosing a change in
pull condition concerns brake cool down. Remember
that pull will return to the original direction, if the
dragging brake unit is allowed to cool down (and is
not seriously damaged).
REAR BRAKE GRAB OR PULL
Rear grab or pull is usually caused by improperly
adjusted or seized parking brake cables, contami-
nated lining, bent or binding shoes and support
plates, or improperly assembled components. This is
particularly true when only one rear wheel is
involved. However, when both rear wheels are
affected, the master cylinder or proportioning valve
could be at fault.BRAKES DO NOT HOLD AFTER DRIVING THROUGH DEEP
WATER PUDDLES
This condition is generally caused by water soaked
lining. If the lining is only wet, it can be dried by
driving with the brakes very lightly applied for a
mile or two. However, if the lining is both soaked and
dirt contaminated, cleaning and/or replacement will
be necessary.
BRAKE LINING CONTAMINATION
Brake lining contamination is mostly a product of
leaking calipers or worn seals, driving through deep
water puddles, or lining that has become covered
with grease and grit during repair. Contaminated lin-
ing should be replaced to avoid further brake prob-
lems.
WHEEL AND TIRE PROBLEMS
Some conditions attributed to brake components
may actually be caused by a wheel or tire problem.
A damaged wheel can cause shudder, vibration and
pull. A worn or damaged tire can also cause pull.
Severely worn tires with very little tread left can
produce a grab-like condition as the tire loses and
recovers traction. Flat-spotted tires can cause vibra-
tion and generate shudder during brake operation. A
tire with internal damage such as a severe bruise,
cut, or ply separation can cause pull and vibration.
BRAKE NOISES
Some brake noise is common with rear drum
brakes and on some disc brakes during the first few
stops after a vehicle has been parked overnight or
stored. This is primarily due to the formation of trace
corrosion (light rust) on metal surfaces. This light
corrosion is typically cleared from the metal surfaces
after a few brake applications causing the noise to
subside.
BRAKE SQUEAK/SQUEAL
Brake squeak or squeal may be due to linings that
are wet or contaminated with brake fluid, grease, or
oil. Glazed linings and rotors with hard spots can
also contribute to squeak. Dirt and foreign material
embedded in the brake lining will also cause squeak/
squeal.
A very loud squeak or squeal is frequently a sign of
severely worn brake lining. If the lining has worn
through to the brake pads in spots, metal-to-metal
contact occurs. If the condition is allowed to continue,
rotors can become so scored that replacement is nec-
essary.
BRAKE CHATTER
Brake chatter is usually caused by loose or worn
components, or glazed/burnt lining. Rotors with hard
spots can also contribute to chatter. Additional causes
5 - 4 BRAKES - BASEDR
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)

INSTALLATION
INSTALLATION - FRONT
(1) Bottom pistons in caliper bore with C-clamp.
Place an old brake shoe between a C-clamp and cal-
iper piston.
(2) Clean caliper mounting adapter and anti-rattle
springs.
(3) Lubricate anti-rattle springs with Mopar brake
grease.
(4) Installnewanti-rattle springs.
NOTE: Anti-rattle springs are not interchangeable.
(5) Install inboard brake shoe in adapter.
(6) Install outboard brake shoe in adapter.(7) Tilt the top of the caliper over rotor and under
adapter. Then push the bottom of the caliper down
onto the adapter.
(8) Install caliper, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION).
(9) Install wheel and tire assemblies and lower
vehicle, (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(10) Apply brakes several times to seat caliper pis-
tons and brake shoes and obtain firm pedal.
(11) Top off master cylinder fluid level.
INSTALLATION - REAR
(1) Clean caliper mounting adapter and anti-rattle
springs.
(2) Lubricate anti-rattle springs with Mopar brake
grease.
(3) Installnewanti-rattle springs.
NOTE: Anti-rattle springs are not interchangeable.
(4) Install inboard brake shoe in adapter.
(5) Install outboard brake shoe in adapter.
(6) Tilt the bottom of the caliper over rotor and
under adapter. Then push the top of the caliper down
onto the adapter.
(7) Install caliper, (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/DISC BRAKE CALIPERS
- INSTALLATION) (Refer to 5 - BRAKES/HYDRAU-
LIC/MECHANICAL/DISC BRAKE CALIPERS -
INSTALLATION).
(8) Install wheel and tire assemblies and lower
vehicle, (Refer to 22 - TIRES/WHEELS/WHEELS -
STANDARD PROCEDURE).
(9) Apply brakes several times to seat caliper pis-
tons and brake shoes and obtain firm pedal.
(10) Top off master cylinder fluid level.
DISC BRAKE CALIPERS
DESCRIPTION
The calipers are a single piston type in the rear
and dual piston type in the front. The calipers are
free to slide laterally, this allows continuous compen-
sation for lining wear.
OPERATION
When the brakes are applied fluid pressure is
exerted against the caliper piston. The fluid pressure
is exerted equally and in all directions. This means
pressure exerted against the caliper piston and
within the caliper bore will be equal (Fig. 24).
Fluid pressure applied to the piston is transmitted
directly to the inboard brake pad. This forces the pad
lining against the inner surface of the disc brake
Fig. 22 Top Anti-Rattle Spring
1 - CALIPER ADAPTER
2 - ANTI-RATTLE SPRING
Fig. 23 Bottom Anti-Rattle Spring
1 - ANTI-RATTLE SPRING
2 - CALIPER ADAPTER
5 - 16 BRAKES - BASEDR
BRAKE PADS/SHOES (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)