2001 DODGE RAM brake fluid

STANDARD PROCEDURE - BLEEDING
The hydraulic booster is generally self-bleeding,
this procedure will normally bleed the air from the
booster. Normal driving and operation of the unit will
remove any remaining trapped air.
(1) Fill power steering pump reservoir.
(2) Disconnect fuel shutdown relay and crank the
engine for several seconds, Refer to Fuel System for
relay location and WARNING.
(3) Check fluid level and add if necessary.
(4) Connect fuel shutdown relay and start the
engine.
(5) Turn the steering wheel slowly from lock to
lock twice.
(6) Stop the engine and discharge the accumulator
by depressing the brake pedal 5 times.
(7) Start the engine and turn the steering wheel
slowly from lock to lock twice.
(8) Turn off the engine and check fluid level and
add if necessary.
NOTE: If fluid foaming occurs, wait for foam to dis-
sipate and repeat steps 7 and 8.
REMOVAL
NOTE: If the booster is being replaced because the
power steering fluid is contaminated, flush the
power steering system before replacing the booster.
(1) With engine off depress the brake pedal 5
times to discharge the accumulator.
(2) Remove brake lines from master cylinder.
(3) Remove mounting nuts from the master cylin-
der.
(4) Remove the bracket from the hydraulic booster
lines and master cylinder mounting studs.
(5) Remove the master cylinder.
(6) Remove the return hose and the two pressure
lines from the hydraulic booster (Fig. 26).
(7) Remove the booster push rod clip, washer and
rod remove from the brake pedal. (Fig. 27).
(8) Remove the mounting nuts from the hydraulic
booster and remove the booster (Fig. 28).
Fig. 26 Master Cylinder And Booster
1 - MASTER CYLINDER
2 - RETURN LINE
3 - LINE FROM PUMP
4 - HYDRAULIC BOOSTER
5 - LINE TO GEAR
Fig. 27 Booster Push Rod
1 - BOOSTER PUSH ROD
2 - WASHER
3 - CLIP
4 - PEDAL
BR/BEBRAKES 5 - 19
POWER BRAKE BOOSTER (Continued)

INSTALLATION
(1) Install the hydraulic booster and tighten the
mounting nuts to 28 N´m (21 ft. lbs.).
(2) Install the booster push rod, washer and clip
onto the brake pedal.
(3) Install the master cylinder on the mounting
studs. and tighten the mounting nuts to 23 N´m (17
ft. lbs.).
(4) Install the brake lines to the master cylinder
and tighten to 19-200 N´m (170-200 in. lbs.).
(5) Install the hydraulic booster line bracket onto
the master cylinder mounting studs.
(6) Install the master cylinder mounting nuts and
tighten to 23 N´m (17 ft. lbs.).
(7) Install the hydraulic booster pressure lines to
the bracket and booster.
(8) Tighten the pressure lines to 28 N´m (21 ft.
lbs.).
NOTE: Inspect o-rings on the pressure line fittings
to insure they are in good condition before installa-
tion. Replace o-rings if necessary.
(9) Install the return hose to the booster.
(10) Bleed base brake system, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL - STAN-
DARD PROCEDURE).
(11) Fill the power steering pump with fluid,
(Refer to 19 - STEERING/PUMP - STANDARD PRO-
CEDURE).
CAUTION: Use only MOPAR power steering fluid or
equivalent. Do not use automatic transmission fluid
and do not overfill.(12) Bleed the hydraulic booster.
ROTORS
DIAGNOSIS AND TESTINGÐDISC BRAKE
ROTOR
The rotor braking surfaces should not be refinished
unless necessary.
Light surface rust and scale can be removed with a
lathe equipped with dual sanding discs. The rotor
surfaces can be restored by machining with a disc
brake lathe if surface scoring and wear are light.
Replace the rotor for the following conditions:
²Severely Scored
²Tapered
²Hard Spots
²Cracked
²Below Minimum Thickness
ROTOR MINIMUM THICKNESS
Measure rotor thickness at the center of the brake
shoe contact surface. Replace the rotor if below min-
imum thickness, or if machining would reduce thick-
ness below the allowable minimum.
Rotor minimum thickness is usually specified on
the rotor hub. The specification is either stamped or
cast into the hub surface.
ROTOR RUNOUT
Check rotor lateral runout with dial indicator
C-3339 (Fig. 29). Excessive lateral runout will cause
brake pedal pulsation and rapid, uneven wear of the
brake shoes. Position the dial indicator plunger
approximately 25.4 mm (1 in.) inward from the rotor
edge.
NOTE: Be sure wheel bearing has zero end play
before checking rotor runout.
Maximum allowable rotor runout is 0.127 mm
(0.005 in.).
ROTOR THICKNESS VARIATION
Variations in rotor thickness will cause pedal pul-
sation, noise and shudder.
Measure rotor thickness at 6 to 12 points around
the rotor face (Fig. 30).
Position the micrometer approximately 25.4 mm (1
in.) from the rotor outer circumference for each mea-
surement.
Thickness should notvaryby more than 0.025 mm
(0.001 in.) from point-to-point on the rotor. Machine
or replace the rotor if necessary.
Fig. 28 Booster Mounting
1 - STEERING COLUMN
2 - MOUNTING NUTS
3 - BOOSTER PEDAL ROD
4 - MOUNTING NUTS
5 - 20 BRAKESBR/BE
POWER BRAKE BOOSTER (Continued)

(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.
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) Install anti-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 bottom of the caliper over rotor and
under adapter. Then push the top 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 BRAKE SHOES-11 inch
(1) Clean and inspect individual brake compo-
nents, (Refer to 5 - BRAKES/HYDRAULIC/ME-
CHANICAL/DRUM - CLEANING).
(2) Lubricate anchor pin and brake shoe contact
pads on support plate with high temperature grease
or Lubriplate (Fig. 50).
Fig. 48 Shoe Hold-Down Springs
Fig. 49 Brake Shoe Removal
Fig. 50 Shoe Contact Surfaces
1 - ANCHOR PIN
2 - SUPPORT PLATE
3 - SHOE CONTACT SURFACES
BR/BEBRAKES 5 - 27
BRAKE PADS/SHOES (Continued)

(6) Position adjuster lever return spring on pivot.
(7) Install adjuster lever.
(8) Attach adjuster cable to adjuster lever. Be sure
cable is properly routed.
(9) Adjust brake shoes to drum with brake gauge.
MASTER CYLINDER
DESCRIPTION
A two-piece master cylinder is used on all models.
The cylinder body containing the primary and sec-
ondary pistons is made of aluminum. The removable
fluid reservoir is made of nylon reinforced with glass
fiber. The reservoir stores reserve brake fluid for the
hydraulic brake circuits. The reservoir is the only
serviceable component.
The fluid compartments of the nylon reservoir are
interconnected to permit fluid level equalization.
However, the equalization feature does not affect cir-
cuit separation in the event of a front or rear brake
malfunction. The reservoir compartments will retain
enough fluid to operate the functioning hydraulic cir-
cuit.
Care must be exercised when removing/installing
the master cylinder connecting lines. The threads in
the cylinder fluid ports can be damaged if care is not
exercised. Start all brake line fittings by hand to
avoid cross threading.
The cylinder reservoir can be replaced when neces-
sary. However, the aluminum body section of the
master cylinder is not a repairable component.
NOTE: If diagnosis indicates that an internal mal-
function has occurred, the aluminum body section
must be replaced as an assembly.
OPERATION
The master cylinder bore contains a primary and
secondary piston. The primary piston supplies
hydraulic pressure to the front brakes. The secondary
piston supplies hydraulic pressure to the rear brakes.
DIAGNOSIS AND TESTING - MASTER
CYLINDER/POWER BOOSTER
(1) Start engine and check booster vacuum hose
connections. A hissing noise indicates vacuum leak.
Correct any vacuum leak before proceeding.
(2) Stop engine and shift transmission into Neu-
tral.
(3) Pump brake pedal until all vacuum reserve in
booster is depleted.
(4) Press and hold brake pedal under light foot
pressure. The pedal should hold firm, if the pedal
falls away master cylinder is faulty (internal leak-
age).
(5) Start engine and note pedal action. It should
fall away slightly under light foot pressure then hold
firm. If no pedal action is discernible, power booster,
vacuum supply, or vacuum check valve is faulty. Pro-
ceed to the POWER BOOSTER VACUUM TEST.
(6) If the POWER BOOSTER VACUUM TEST
passes, rebuild booster vacuum reserve as follows:
Release brake pedal. Increase engine speed to 1500
rpm, close the throttle and immediately turn off igni-
tion to stop engine.
(7) Wait a minimum of 90 seconds and try brake
action again. Booster should provide two or more vac-
uum assisted pedal applications. If vacuum assist is
not provided, booster is faulty.
POWER BOOSTER VACUUM TEST
(1) Connect vacuum gauge to booster check valve
with short length of hose and T-fitting (Fig. 54).
(2) Start and run engine at curb idle speed for one
minute.
(3) Observe the vacuum supply. If vacuum supply
is not adequate, repair vacuum supply.
(4) Clamp hose shut between vacuum source and
check valve.
(5) Stop engine and observe vacuum gauge.
(6) If vacuum drops more than one inch HG (33
millibars) within 15 seconds, booster diaphragm or
check valve is faulty.
POWER BOOSTER CHECK VALVE TEST
(1) Disconnect vacuum hose from check valve.
(2) Remove check valve and valve seal from
booster.
(3) Use a hand operated vacuum pump for test.
(4) Apply 15-20 inches vacuum at large end of
check valve (Fig. 55).
Fig. 53 Hold-Down Spring And Pin Attachment
1 - SHOE HOLD DOWN SPRING
2 - HOLD DOWN PIN
3 - BACKING PLATE
4 - BRAKE SHOE WEB
BR/BEBRAKES 5 - 29
BRAKE PADS/SHOES (Continued)

(5) Vacuum should hold steady. If gauge on pump
indicates vacuum loss, check valve is faulty and
should be replaced.
STANDARD PROCEDUREÐMASTER CYLINDER
BLEEDING
A new master cylinder should be bled before instal-
lation on the vehicle. Required bleeding tools include
bleed tubes and a wood dowel to stroke the pistons.
Bleed tubes can be fabricated from brake line.
(1) Mount master cylinder in vise.
(2) Attach bleed tubes to cylinder outlet ports.
Then position each tube end into reservoir (Fig. 56).
(3) Fill reservoir with fresh brake fluid.
(4) Press cylinder pistons inward with wood dowel.
Then release pistons and allow them to return under
spring pressure. Continue bleeding operations until
air bubbles are no longer visible in fluid.
REMOVAL
(1) Pump the brake pedal several times to deplete
booster vacuum reserve.
(2) Remove brake lines from the master cylinder
(Fig. 57).
(3) Remove mounting nuts from the master cylin-
der (Fig. 57).
(4) Remove the master cylinder.
INSTALLATION
NOTE: If master cylinder is replaced, bleed cylinder
before installation.
(1) Install master cylinder on the booster mount-
ing studs.
(2) Install mounting nuts and tighten to 23 N´m
(17 ft. lbs.).
(3) Install brake lines and tighten to 19-23 N´m
(170-200 in. lbs.).
Fig. 54 Typical Booster Vacuum Test Connections
1 - TEE FITTING
2 - SHORT CONNECTING HOSE
3 - CHECK VALVE
4 - CHECK VALVE HOSE
5 - CLAMP TOOL
6 - INTAKE MANIFOLD
7 - VACUUM GAUGE
Fig. 55 Vacuum Check Valve And Seal
1 - BOOSTER CHECK VALVE
2 - APPLY TEST VACUUM HERE
3 - VALVE SEAL
Fig. 56 Master Cylinder Bleeding±Typical
1 - BLEEDING TUBES
2 - RESERVOIR
5 - 30 BRAKESBR/BE
MASTER CYLINDER (Continued)

(4) Bleed base brake system, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL - STAN-
DARD PROCEDURE)
WHEEL CYLINDERS
REMOVAL
(1) Raise vehicle and remove tire and wheel
assembly.
(2) Remove brake drum.
(3) Lift adjuster lever away from adjuster screw.
Then turn screw star wheel until screw is fully
retracted.
(4) Remove brake shoe return springs, adjuster
spring and adjuster screw. Move upper ends of brake
shoes apart to provide removal clearance for wheel
cylinder links.
(5) Disconnect brake line from wheel cylinder.
(6) Remove wheel cylinder attaching screws and
remove cylinder from support plate
DISASSEMBLY
(1) Remove push rods and boots (Fig. 58).
(2) Press pistons, cups and spring and expander
out of cylinder bore.
(3) Remove bleed screw.
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 cylindercomponents. 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.
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.
Fig. 57 Master Cylinder
1 - MOUNTING NUT
2 - MOUNTING NUT
3 - BRAKE LINES
4 - MASTER CYLINDER
Fig. 58 Wheel Cylinder Components±Typical
1 - SPRING
2 - CYLINDER
3 - PISTON CLIP
4 - BOOT
5 - PUSH ROD
6 - PISTON
7 - BLEED SCREW
8 - CUP EXPANDERS
BR/BEBRAKES 5 - 31
MASTER CYLINDER (Continued)

INSTALLATION
(1) Apply thin coat of silicone sealer to wheel cyl-
inder mounting surface of support plate (Fig. 59).
Sealer prevents road splash from entering brake
drum past cylinder.
(2) Start brake line in cylinder inlet by hand. Do
not tighten fitting at this time.
(3) Mount wheel cylinder on support plate and
install cylinder attaching screws. Tighten screws to
20 N´m (15 ft. lbs.).
(4) Tighten brake line fitting to 13 N´m (115 in.
lbs.).
(5) Install brake shoe components.
(6) Adjust brake shoes to drum using brake gauge.
(7) Install brake drum.
(8) Bleed base brake system, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL - STAN-
DARD PROCEDURE).
(9) Install wheel and tire assemblies, (Refer to 22 -
TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE) and lower vehicle.
SUPPORT PLATE
REMOVAL
(1) Remove wheel and tire assemblies.
(2) Remove brake drums
(3) Remove axle shaft, (Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE - 9 1/4/AXLE
SHAFTS - REMOVAL).
(4) Remove brake shoes and hardware for access to
parking brake cable.
(5) Remove parking brake cable from support
plate.(6) Disconnect brake line at wheel cylinder and
remove cylinder.
(7) Remove bolts attaching support plate to axle
and remove support plate.
INSTALLATION
(1) Apply thin bead of silicone sealer around axle
mounting surface of support plate.
(2) Install support plate on axle flange. Tighten
attaching bolts to 47-68 N´m (35-50 ft. lbs.).
(3) Apply thin bead of silicone sealer around wheel
cylinder mounting surface. Install wheel cylinder on
new support plate.
(4) Install parking brake cable in support plate.
(5) Install brake shoes and hardware.
(6) Install axle shaft, (Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE - 9 1/4/AXLE
SHAFTS - INSTALLATION).
(7) Adjust brake shoes to drum with brake gauge.
(8) Install brake drums.
(9) Fill and bleed brake system, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL - STAN-
DARD PROCEDURE).
(10) Install wheel and tire assemblies, (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE) and lower vehicle.
DRUM
DESCRIPTION
All 1500 models and early year production
2500/3500 are equipped with rear drum brake assem-
blies. They are two-shoe, duo-servo units with an
automatic adjuster mechanism.
Drum brake assemblies used:
²1500 models: 11 x 2.25 in.
²2500/3500 models: 12 1/8 x3.5 in.
The drum brakes are a semi-floating, self-energiz-
ing, servo action design. The brake shoes are not
fixed on the support plate. This type of brake allows
the shoes to pivot and move vertically to a certain
extent.
OPERATION
In operation, fluid apply pressure causes the wheel
cylinder pistons to move outward. This movement is
transferred directly to the brake shoes by the cylin-
der connecting links. The resulting brake shoe expan-
sion brings the lining material into contact with the
rotating brake drum.
Two forces affect the brake shoes once they contact
the drum. The first force being hydraulic pressure
exerted through the wheel cylinder pistons. And the
second force is the friction generated turning torque
of the rotating drum.
Fig. 59 Wheel Cylinder Mounting Surface
1 - CYLINDER MOUNTING SURFACE
2 - SUPPORT PLATE
3 - APPLY THIN SEALER COAT HERE
5 - 32 BRAKESBR/BE
WHEEL CYLINDERS (Continued)

INSTALLATION
(1) Inspect bushings in clutch and brake pedals
(Fig. 33). Replace bushings if worn, cracked, or dis-
torted.(2) Lubricate pedal shaft, pedal shaft bore (Fig. 33)
and all bushings with MopartMulti Mileage, or high
temperature bearing grease.
(3) Position clutch pedal in support. Align pedal
with pivot shaft and slide shaft through pedal bush-
ings. Then repeat process for brake pedal.
(4) Slide pedal shaft through support and install
shaft retainer.
(5) Secure push rods to clutch and brake pedals.
(6) Install brake lamp switch in bracket.
(7) Install knee bolster.
LINKAGE
DESCRIPTION
The hydraulic linkage consists of a clutch master
cylinder, reservoir, a clutch slave cylinder and an
interconnecting fluid line 9 (Fig 34).
The clutch master cylinder push rod is connected
to the clutch pedal. The slave cylinder push rod is
connected to the clutch release fork. The master cyl-
inder is mounted on the driver side of the dash panel
adjacent to the brake master cylinder and booster
assembly.
The hydraulic linkage is serviced as an assembly only.
The individual components that form the linkage
assembly cannot be overhauled or serviced separately.
Fig. 32 Knee Bolster RemovalÐTypical
1 - INSTRUMENT PANEL FLANGES
2 - KNEE BOLSTER
Fig. 33 Clutch/Brake Pedal Mounting
1 - PEDAL SUPPORT
2 - SHAFT RETAINER
3 - BRAKE PEDAL
4 - CLUTCH PEDAL
5 - SHAFT RETAINER
6 - PEDAL PIVOT SHAFT
7 - BUSHINGS
Fig. 34 Clutch
1 - DASH PANEL
2 - CYLINDER RESERVOIR
3 - CLUTCH MASTER CYLINDER
4 - SLAVE CYLINDER
5 - CLUTCH HYDRAULIC LINE
BR/BECLUTCH 6 - 19
CLUTCH PEDAL (Continued)