DODGE RAM 2003 Service Repair Manual

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 shoes
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 wheel cylinders, worn seals, driv-
ing through deep water puddles, or lining that hasbecome covered with grease and grit during repair.
Contaminated lining should be replaced to avoid fur-
ther brake problems.
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 shoes in spots, metal-to-metal
contact occurs. If the condition is allowed to continue,
rotors and drums can become so scored that replace-
ment is necessary.
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
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. In addition, worn out,
improperly adjusted, or improperly assembled rear
brake shoes can also produce a thump noise.
5 - 4 BRAKES - BASEDR
BRAKES - BASE (Continued)

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, or wheel cylinders were overhauled,
open all caliper and wheel cylinder bleed screws.
Then close each bleed screw as fluid starts to drip
from it. Top off master cylinder reservoir 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.
(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.
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 thetank 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
HANDLE C-4171
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).
HYDRAULIC/MECHANICAL
SPECIFICATIONS
SPECIFICATIONS - TORQUE CHART
TORQUE SPECIFICATIONS
DESCRIPTION N´m Ft. Lbs. In. Lbs.
Brake Booster
Mounting Nuts38 28 Ð
Master Cylinder
Mounting Nuts18 Ð 160
Caliper
Mounting Pins32 24 Ð
Caliper
Adapter Mounting Bolts176 130 Ð
Junction Block
Bolts To Frame10 7.5 Ð
Brake Pedal Assembly Bracket
Nuts28 21 Ð
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
3 - PEDAL SWITCH ELECTRICAL CONNECTOR
4 - BEZEL
5 - 6 BRAKES - BASEDR
BRAKES - BASE (Continued)

DESCRIPTION N´m Ft. Lbs. In. Lbs.
Support Plate
Mounting Bolts/Nuts64 47 Ð
Brake Line Fittings
Master Cylinder19 14 170
Brake Line Fittings
Junction Block19 14 170
Caliper
Brake Line Banjo Bolt27 20 245
Brake Hose
Front Bolts To Frame10 7.5 Ð
Brake Hose
Front Fitting19 14 250
Brake Hose
Rear Fitting19 14 250
Parking Brake Pedal Assembly 19 14 250
Hub/Bearing
Bolts163 120 Ð
BASE BRAKE
SPECIFICATIONS
DESCRIPTION SPECIFICATION
Front Disc Brake Caliper
TypeDual Piston Sliding
Rear Disc Brake Caliper
TypeSingle Piston Sliding
Front Disc Brake Caliper 54 mm (2.00 in.)
Front Disc Brake Rotor 336ý28 mm (13.2ý1.1
in.)
Front/Rear Disc Brake
Rotor
Max. Runout0.127 mm (0.005 in.)
Front/Rear Disc Brake
Rotor
Max. Thickness Variation0.025 mm (0.001 in.)
Minimum Front Rotor
Thickness26.4 mm (1.039 in.)
Mininium Rear Rotor
Thickness28.39 mm (1.117 in)
Rear Disc Brake Caliper 1x54 mm (2.12 in)
Rear Disc Brake Rotor 350x22 mm (.86 in)
Brake Booster
Type
Gasoline EnginesVacuum Dual Diaphragm
BRAKE LINES
STANDARD PROCEDURE
STANDARD PROCEDURE - DOUBLE INVERTED
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.
(1) Cut off damaged tube with Tubing Cutter.
(2) Ream cut edges of tubing to ensure proper
flare.
(3) Install replacement tube nut on the tube.
(4) Insert tube in flaring tool.
(5) Place gauge form over the end of the tube.
(6) Push tubing through flaring tool jaws until
tube contacts recessed notch in gauge that matches
tube diameter.
(7) Tighten the tool bar on the tube
(8) Insert plug on gauge in the tube. Then swing
compression disc over gauge and center tapered flar-
ing screw in recess of compression disc (Fig. 3).
(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
DRBRAKES - BASE 5 - 7
HYDRAULIC/MECHANICAL (Continued)

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. 4). 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. 4).
(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. 5).
(4) Remove the brake hose clip at the top of the
hose located at the frame (Fig. 5).
(5) Remove the vent tube (Fig. 6).
(6) Remove the two brake lines at the bottom of
the hose located at the axle (Fig. 6).
(7) Remove the mounting bolt for the brake hose
at the axle (Fig. 6).
(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. 7).
Fig. 3 Inverted Flare Tools
Fig. 4 ISO Flaring
1 - ADAPTER
2 - LUBRICATE HERE
3 - PILOT
4 - FLUSH WITH BAR
5 - TUBING
6 - BAR ASSEMBLY
Fig. 5 BRAKE LINE CLIP
1 - BRAKE HOSE
2 - CLIP
3 - BRAKE LINE
5 - 8 BRAKES - BASEDR
BRAKE LINES (Continued)

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

(3) Install the brake hose banjo bolt at the caliper
(Fig. 8).
(4) Reinstall the wheel speed sensor wire to the
brake hose (Fig. 8).
(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
(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. 10).
NOTE: Do not allow brake hose to support caliper
assembly.
(6) Support and hang the caliper. (Fig. 11)
(7) Remove the inboard brake shoe from the cali-
per adapter (Fig. 12).
(8) Remove the outboard brake shoe from the cali-
per adapter (Fig. 13).
(9) Remove the anti-rattle springs from the caliper
adapter (Fig. 14) and (Fig. 15).
NOTE: Anti-rattle springs are not interchangeable.
INSTALLATION
(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) Install anti-rattle springs.
NOTE: Anti-rattle springs are not interchangeable.
(5) Install inboard brake shoe in adapter.
Fig. 9 BRAKE HOSE MOUNT DRIVERS SIDE
1 - MOUNTING BOLT
2 - WHEEL SPEED SENSOR WIRE
3 - BRAKE HOSE
Fig. 10 Caliper
1 - CALIPER
2 - CALIPER ADAPTER
Fig. 11 DISC BRAKE CALIPER - FRONT
1 - STEERING KNUCKLE
2 - DISC BRAKE CALIPER
3 - CALIPER MOUNTING ADAPTER
4 - DISC BRAKE ROTOR
5 - 10 BRAKES - BASEDR
BRAKE LINES (Continued)

(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.
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.
Fig. 12 Inboard Brake Shoe
1 - INBOARD SHOE
2 - CALIPER ADAPTER
Fig. 13 Outboard Brake Shoe
1 - OUTBOARD SHOE
2 - CALIPER ADAPTER
Fig. 14 Top Anti-Rattle Spring
1 - CALIPER ADAPTER
2 - ANTI-RATTLE SPRING
Fig. 15 Bottom Anti-Rattle Spring
1 - ANTI-RATTLE SPRING
2 - CALIPER ADAPTER
DRBRAKES - BASE 5 - 11
BRAKE PADS/SHOES (Continued)

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. 16).
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
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 gettingbetween 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.
17). 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 amount
is just enough to maintain contact between the pis-
ton and inboard brake pad.
REMOVAL
REMOVAL - REAR
(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 if replacing
caliper (Fig. 18).
(6) Remove the caliper mounting slide pin bolts
(Fig. 18).
(7) Remove the caliper from vehicle.
REMOVAL - FRONT
CAUTION: Never allow the disc brake caliper to
hang from the brake hose. Damage to the brake
hose with 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.
Fig. 16 Brake Caliper Operation
1 - CALIPER
2 - PISTON
3 - PISTON BORE
4 - SEAL
5 - INBOARD SHOE
6 - OUTBOARD SHOE
Fig. 17 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
5 - 12 BRAKES - BASEDR
DISC BRAKE CALIPERS (Continued)

(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 pin bolts.
(7) Remove the disc brake caliper (Fig. 19) or (Fig.
20).
DISASSEMBLY
(1) Drain the brake fluid from caliper.
(2) C-clamp a block of wood over one piston (Fig.
21).
(3) Take another piece of wood and pad it with
one-inch thickness of shop towels. Place this piece in
the outboard shoe side of the caliper in front of the
other piston. This will cushion and protect caliper
piston during removal (Fig. 22).
(4) To remove the caliper piston directshort
bursts of low pressure airwith a blow gun
through the caliper brake hose port. Use only enough
air pressure to ease the piston out.
Fig. 18 DISC BRAKE CALIPER - REAR
1 - CALIPER ADAPTER
2 - CALIPER ADAPTER MOUNTING BOLTS
3 - CALIPER SLIDE BOLTS
4 - BRAKE HOSE
5 - CABLE
6 - CALIPER
7 - ROTOR
8 - ANTI-RATTLE CLIPS
Fig. 19 DISC BRAKE CALIPER - FRONT
1 - STEERING KNUCKLE
2 - DISC BRAKE CALIPER
3 - CALIPER MOUNTING ADAPTER
4 - DISC BRAKE ROTOR
Fig. 20 8 LUG ROTOR & CALIPER ASSEMBLY
1 - ROTOR
2 - CALIPER ADAPTER
3 - ANTI-RATTLE CLIPS
4 - BRAKE HOSE WITH BANJO BOLT
5 - DISC BRAKE CALIPER
6 - OUTBOARD BRAKE PAD
Fig. 21 C-Clamp One Piston
1 - BLOCK OF WOOD
2 - C-CLAMP
3 - CALIPER
DRBRAKES - BASE 5 - 13
DISC BRAKE CALIPERS (Continued)