service DODGE RAM 2003 Service Owner's Guide

PINION GEAR/RING GEAR/
TONE RING
REMOVAL
NOTE: The ring and pinion gears are service in a
matched set. Never replace the ring gear/pinion
gear without replacing the other matching gear.
(1) Mark pinion flange and propeller shaft for
installation alignment.
(2) Disconnect propeller shaft from pinion flange
and remove propeller shaft.
(3) Remove differential from the housing.
(4) Place differential on Plug 8964. Drive exciter
ring off the differential case with a hammer and
punch (Fig. 49).
NOTE: Do not remove the exciter ring if it is not
being replaced.
(5) Place differential case in a vise with soft metal
jaw protectors(6) Remove bolts holding ring gear to differential
case.
(7) Drive ring gear from differential case with a
soft hammer (Fig. 50).
(8) Hold pinion flange with Flange Wrench 8979
(Fig. 51) and remove pinion flange nut.
Fig. 49 EXCITER RING
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - PUNCH
4 - EXCITER RING
Fig. 50 RING GEAR
1 - DIFFERENTIAL CASE
2 - RING GEAR
3 - HAMMER
Fig. 51 FLANGE WRENCH
1 - PINION FLANGE
2 - FLANGE WRENCH
DRREAR AXLE - 11 1/2 AA 3 - 149

FLUID RESERVOIR
REMOVAL
(1) Install the prop rod on the brake pedal to keep
pressure on the brake system.
(2) Remove the reservoir cap and siphon fluid into
a drain container (Fig. 34).
(3) Remove the electrical connector from the fluid
level switch in the reservoir (Fig. 34).
(4) Remove the reservoir mounting bolt (Fig. 34).
(5) Remove the reservoir from the master cylinder
by pulling upwards.
(6) Remove old grommets from cylinder body (Fig.
34).
INSTALLATION
CAUTION: Do not use any type of tool to install the
grommets. Tools may cut, or tear the grommets cre-
ating a leak problem after installation. Install the
grommets using finger pressure only.
(1) Lubricate the new grommets with clean brake
fluid and Install new grommets in cylinder body. Use
finger pressure to install and seat grommets.
(2) Start the reservoir in grommets. Then rock the
reservoir back and forth while pressing downward to
seat it into the grommets.
(3) Install the mounting bolt for the reservoir to
the master cylinder.
(4) Reconnect the electrical connector to the fluid
reservoir level switch.
(5) Remove the prop rod from the vehicle.(6) Fill and bleed base brake system,(Refer to 5 -
BRAKES - STANDARD PROCEDURE).
BRAKE JUNCTION BLOCK
REMOVAL
(1) Remove the brake lines from the junction block
(Fig. 35).
(2) Remove the junction block mounting bolt and
remove the junction block from the bracket (Fig. 35).
INSTALLATION
(1) Position the junction block on the bracket and
install the mounting bolt. Tighten the mounting bolt
to 23 N´m (210 in. lbs.) (Fig. 35).
(2) Install the brake lines into the junction block
and tighten to 19-23 N´m (170-200 in. lbs.) (Fig. 35).
(3) Bleed the base brake system, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL - STAN-
DARD PROCEDURE).
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 and has a switch for indicat-
ing low fluid levels. The reservoir is the only service-
able component.
The fluid compartments of the nylon reservoir are
interconnected to permit fluid level equalization.
However, the equalization feature does not affect cir-
Fig. 34 FLUID RESERVOIR
1 - MASTER CYLINDER CAP
2 - FLUID RESERVOIR
3 - FLUID LEVEL SWITCH
4 - MASTER CYLINDER
5 - MOUNTING BOLT
6 - GROMMETS
Fig. 35 JUNCTION BLOCK
1 - BRAKE LINES
2 - JUNCTION BLOCK
DRBRAKES - BASE 5 - 19

NOTE: Using care remove the master cylinder
directly forward in order not to dislodge the output
rod from its seat inside the booster.
INSTALLATION
INSTALLATION - ALL EXCEPT HYDROBOOST
NOTE: If master cylinder is replaced bleed cylinder
before installation.
NOTE: Make sure the output rod of the brake
booster is in position before mounting of the mas-
ter cylinder ªThis position will enable the output
rod to enter inside of the master cylinder plunger
sleeve during installationº. Proper position is
obtained when the output rod is centered perpen-
dicular to the master cylinder mounting hole (Fig.
41).
NOTE: Before installing the master cylinder, pump
the brake pedal several times with the engine off to
remove vacuum from the booster.
(1) Install the master cylinder on the booster
mounting studs.
(2) Install new mounting nuts and tighten to 25
N´m (221 in. lbs.)
(3) Install the brake lines and tighten to 19 N´m
(170 in. lbs.)(4) Reconnect the elctrical connector for the low
fluid level switch.
(5) Fill and bleed the base brake system. (Refer to
5 - BRAKES - STANDARD PROCEDURE).
INSTALLATION - HYDROBOOST
NOTE: If master cylinder is replaced bleed cylinder
before installation.
NOTE: Make sure the output rod of the brake
booster is in position before mounting of the mas-
ter cylinder ªThis position will enable the output
rod to enter inside of the master cylinder plunger
sleeve during installationº. Proper position is
obtained when the output rod is centered perpen-
dicular to the master cylinder mounting hole (Fig.
41).
(1) Install the master cylinder on the booster
mounting studs (Fig. 40).
(2) Install new mounting nuts and tighten to 25
N´m (221 in. lbs.)
(3) Install the brake lines and tighten to 19 N´m
(170 in. lbs.)
(4) Reconnect the elctrical connector for the low
fluid level switch.
(5) Fill and bleed the base brake system. (Refer to
5 - BRAKES - STANDARD PROCEDURE).
PEDAL
DESCRIPTION
NOTE: The brake pedal is serviced as a complete
assembly including accelerator pedal and the
bracket.
A suspended-type brake pedal is used. The pedal is
attached to the pedal support bracket with a pivot
shaft pin and bushings. If the bushings become dry a
spray lubricant can be used to eliminate noises. The
booster push rod is attached to the pedal with a clip.
The pedal, bushings, pivot pin and support bracket
are not serviceable components (Fig. 42).
OPERATION
The brake pedal is attached to the booster push
rod. When the pedal is depressed, the primary
booster push rod is depressed which move the booster
secondary rod. The booster secondary rod depress the
master cylinder piston.
Fig. 41 OUTPUT ROD ORIENTATION
1 - MASTER CYLINDER RESERVOIR
2 - CHECK VALVE
3 - BOOSTER
4 - BOOSTER MOUNTING STUDS
5 - INPUT ROD
6 - OUTPUT ROD
7 - MASTER CYLINDER MOUNTING STUDS
8 - MASTER CYLINDER
9- ELECTRICAL CONNECTOR
5 - 22 BRAKES - BASEDR
MASTER CYLINDER (Continued)

REMOVAL
NOTE: The brake pedal is serviced as a complete
assembly including accelerator pedal and the
bracket.
(1) Disconnect the negative battery cable.
(2) Remove the steering column opening cover(Re-
fer to 23 - BODY/INSTRUMENT PANEL/STEERING
COLUMN OPENING COVER - REMOVAL).
(3) Remove the brake lamp switch and discard(Re-
fer to 8 - ELECTRICAL/LAMPS/LIGHTING - EXTE-
RIOR/BRAKE LAMP SWITCH - REMOVAL).
(4)On vehicles equipped with adjustable ped-
als.Disconnect the adjuster cable to the pedal (Fig.
43).
(5) Remove the steering column (Refer to 19 -
STEERING/COLUMN - REMOVAL).
(6) Remove the brake booster (Fig. 44)(Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/POWER
BRAKE BOOSTER - REMOVAL).
(7) Disconnect the electrical connectors.
(8) Remove the module mounting bolts.
(9) Disconnect the accelerator pedal cable.
(10) Remove the pedal assembly mounting nuts/
fasteners (Fig. 44).
INSTALLATION
(1) Install the pedal assembly to the vehicle (Fig.
44).
(2) Install the mounting bolts (Fig. 44) and tighten
to 28 N´m (21 ft. lbs.).
(3) Reconnect the accelerator cable to the pedal.(4) Install the module mounting bolts and tighten
to 38 N´m (28 ft. lbs.).
(5) Reconnect the electrical connectors.
(6) Install the brake booster (Refer to 5 - BRAKES/
HYDRAULIC/MECHANICAL/POWER BRAKE
BOOSTER - INSTALLATION).
(7) Install the steering column (Refer to 19 -
STEERING/COLUMN - INSTALLATION).
(8) Install a new brake lamp switch. (Refer to 8 -
ELECTRICAL/LAMPS/LIGHTING - EXTERIOR/
BRAKE LAMP SWITCH - REMOVAL).
(9)On vehicles equipped with adjustable
brake pedal.Reconnect the electrical connector to
the motor and the adjuster cable at the pedal.
Fig. 42 BRAKE PEDAL
1 - CLIP
2 - BUSHINGS
3 - PIVOT SHAFT PIN
4 - PEDAL ASSEMBLY
ADJUSTABLE PEDAL SHOWN
NON ADJUSTABLE PEDAL IS SIMILIAR
5-PAD
Fig. 43 PEDAL/CABLE
1 - CABLE
2 - BRAKE PEDAL ASSEMBLY
Fig. 44 PEDAL ASSEMBLY (ADJUSTABLE PEDALS
SHOWN)
1 - ADJUSTABLE PEDAL MOTOR
2 - PEDAL ASSEMBLY BRACKET
3 - MOUNTING NUT
4 - BRAKE & ACCELERATOR PEDAL
5 - BRAKE BOOSTER MOUNTING STUDS
DRBRAKES - BASE 5 - 23
PEDAL (Continued)

(10) Install the steering column opening cover
(Refer to 23 - BODY/INSTRUMENT PANEL/STEER-
ING COLUMN OPENING COVER - INSTALLA-
TION).
(11) Reconnect the negative battery cable.
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.
45). 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. 45) 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)
²Pedal Adjustment Inhibitors: Pedal adjust-
ment is inhibited when the vehicle is in reverse or
when cruise control is activated.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Remove the kneeblocker (Refer to 23 - BODY/
INSTRUMENT PANEL/STEERING COLUMN
OPENING COVER - REMOVAL).
(3) Remove the brake light switch and discard
(Refer to 8 - ELECTRICAL/LAMPS/LIGHTING -
EXTERIOR/BRAKE LAMP SWITCH - REMOVAL).
(4) Disconnect the adjustable pedal cables from the
brake and accelerator pedals.
(5) Disconnect the electrical connector.
(6) Unclip the cable fasteners to the support.(7) Remove the one mounting bolt for the adjust-
able pedal motor (Fig. 46).
(8) Remove the adjustable pedal motor with the
cables.
NOTE: Adjustable pedal cables are not serviceable.
If they need service the adjustable pedal motor with
the cables must be installed.
INSTALLATION
NOTE: Adjustable pedal cables are not serviceable.
If they need service the adjustable pedal motor with
the cables must be installed.
(1) Install the adjustable pedal motor with the
cables.
Fig. 45 ADJUSTABLE PEDAL MOTOR
1 - ADJUSTABLE PEDAL MOTOR
2 - CABLES
3 - ELECTRICAL CONNECTOR
Fig. 46 ADJUSTABLE PEDAL MOTOR
1 - ADJUSTABLE PEDAL MOTOR
2 - MOUNTING BOLT
5 - 24 BRAKES - BASEDR
PEDAL (Continued)

(2) Install the caliper adapter (Fig. 50) (Refer to 5
- BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPER ADAPTER - INSTALLATION).
(3) Install the caliper adapter bolts (Fig. 50) and
tighten the mounting bolts to 135 N´m (100 ft.lbs).
(4) Install the disc brake caliper, (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPERS - INSTALLATION).
(5) Install the tire and wheel assembly (Refer to 22
- TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
(6) Lower the vehicle.
INSTALLATION - FRONT
(1) On models with all-wheel antilock system
(ABS), check condition of tone wheel on hub/bearing.
If teeth on wheel are damaged, hub/bearing assembly
will have to be replaced (tone wheel is not serviced
separately).
(2) Install the rotor onto the hub/bearing wheel
studs.
(3) Install the caliper adapter assembly,(Refer to 5
- BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPERS - INSTALLATION) and tighten
adapter bolts to:
(4) Install the wheel and tire assembly, (Refer to
22 - TIRES/WHEELS/WHEELS - STANDARD PRO-
CEDURE) and lower the vehicle.
(5) Apply the brakes several times to seat brake
pads. Be sure to obtain firm pedal before moving
vehicle.
SUPPORT PLATE
REMOVAL
(1) Remove wheel and tire assembly.
(2) Remove the disc brake caliper (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPERS - REMOVAL).
(3) Remove the caliper adapter (Refer to 5 -
BRAKES/HYDRAULIC/MECHANICAL/DISC
BRAKE CALIPER ADAPTER - REMOVAL).
(4) Remove the rotor (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTORS - REMOVAL).
(5) Remove the axle shaft (Refer to 3 - DIFFER-
ENTIAL & DRIVELINE/REAR AXLE - 9 1/4/AXLE
SHAFTS - REMOVAL).
(6) Remove the park brake shoes (Refer to 5 -
BRAKES/PARKING BRAKE/SHOES - REMOVAL).
(7) Remove the parking brake cable from the
brake lever.
(8) Remove the bolts attaching the support plate to
the axle and remove the support plate (Fig. 54).
INSTALLATION
(1) Install support plate on axle flange (Fig. 55).
Tighten attaching bolts to 115 N´m (85 ft. lbs.).
(2) Install parking brake cable in the brake lever.
(3) Install the park brake shoes (Refer to 5 -
BRAKES/PARKING BRAKE/SHOES - INSTALLA-
TION). (Fig. 55).
(4) Install axle shaft, (Refer to 3 - DIFFEREN-
TIAL & DRIVELINE/REAR AXLE - 9 1/4/AXLE
SHAFTS - INSTALLATION).
(5) Adjust brake shoes to drum with brake gauge
(Refer to 5 - BRAKES/PARKING BRAKE/SHOES -
ADJUSTMENTS).
Fig. 52 FRONT ROTOR
1 - ROTOR
2 - HUB/BEARING
Fig. 53 8 LUG ROTOR ASSEMBLY
1 - SPRING
2 - SHOCK
3 - UPPER AND LOWER SUSPENSION ARMS
4 - DISC BRAKE CALIPER
5 - DISC BRAKE CALIPER ADAPTER
6 - ROTOR
DRBRAKES - BASE 5 - 29
ROTORS (Continued)

(5) Tighten the front cable grommet to the floor-
pan and the cable retainer, roll the carpet back.
(6) Connect the wires to the brake lamp switch.
(7) Install the knee bolster, (Refer to 23 - BODY/
INSTRUMENT PANEL/STEERING COLUMN
OPENING COVER - INSTALLATION).
(8) Raise the vehicle.
(9) Adjust the parking brake cable tensioner (Refer
to 5 - BRAKES/PARKING BRAKE/CABLE TEN-
SIONER - ADJUSTMENTS).
CABLE TENSIONER
ADJUSTMENTS
ADJUSTMENT
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 the vehicle.
(2) Back off the cable tensioner adjusting nut to
create slack in the cables.
(3) Remove the rear wheel/tire assemblies. Then
remove the brake rotors (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTORS - REMOVAL).
(4) Verify the brakes are in good condition and
operating properly.
(5) Verify the park brake cables operate freely and
are not binding, or seized.(6) Check the rear brake shoe adjustment with
standard brake gauge (Refer to 5 - BRAKES/PARK-
ING BRAKE/SHOES - ADJUSTMENTS).
(7) Install the rotors (Refer to 5 - BRAKES/HY-
DRAULIC/MECHANICAL/ROTORS - INSTALLA-
TION) and verify that the rotors rotate freely
without drag.
(8) Install the wheel/tire assemblies, (Refer to 22 -
TIRES/WHEELS/WHEELS - STANDARD PROCE-
DURE).
(9) Lower the vehicle enough for access to the park
brake foot pedal. Then fully apply the park brakes.
NOTE: Leave park brakes applied until adjustment
is complete.
(10) Raise the vehicle again.
(11) Mark the tensioner rod 6.35 mm (1/4 in.) from
edge of the tensioner (Fig. 73).
(12) Tighten the adjusting nut on the tensioner rod
until the mark is no longer visible.
CAUTION: Do not loosen, or tighten the tensioner
adjusting nut for any reason after completing
adjustment.
(13) Lower the vehicle until the rear wheels are
15-20 cm (6-8 in.) off the shop floor.
(14) Release the park brake foot pedal and verify
that rear wheels rotate freely without drag. Then
lower the vehicle.
Fig. 72 PARKING BRAKE ASSEMBLY
1 - PEDAL ASSEMBLY
2 - MOUNTING NUT
Fig. 73 Adjustment Mark
1 - TENSIONER CABLE BRACKET
2 - TENSIONER
3 - CABLE CONNECTOR
4 - 6.35mm
(1/4 IN.)
5 - ADJUSTER NUT
DRBRAKES - BASE 5 - 37
PEDAL (Continued)

WARNING
WARNING:: EXERCISE CARE WHEN SERVICING
CLUTCH COMPONENTS. FACTORY INSTALLED
CLUTCH DISCS DO NOT CONTAIN ASBESTOS
FIBERS. DUST AND DIRT ON CLUTCH PARTS MAY
CONTAIN ASBESTOS FIBERS FROM AFTERMAR-
KET COMPONENTS. BREATHING EXCESSIVE CON-
CENTRATIONS OF THESE FIBERS CAN CAUSE
SERIOUS BODILY HARM. WEAR A RESPIRATOR
DURING SERVICE AND NEVER CLEAN CLUTCH
COMPONENTS WITH COMPRESSED AIR OR WITH
A DRY BRUSH. EITHER CLEAN THE COMPONENTS
WITH A WATER DAMPENED RAGS OR USE A VAC-
UUM CLEANER SPECIFICALLY DESIGNED FOR
REMOVING ASBESTOS FIBERS AND DUST. DO NOT
CREATE DUST BY SANDING A CLUTCH DISC.
REPLACE THE DISC IF THE FRICTION MATERIAL IS
DAMAGED OR CONTAMINATED. DISPOSE OF ALL
DUST AND DIRT CONTAINING ASBESTOS FIBERS
IN SEALED BAGS OR CONTAINERS. THIS WILL
HELP MINIMIZE EXPOSURE TO YOURSELF AND TO
OTHERS. FOLLOW ALL RECOMMENDED SAFETY
PRACTICES PRESCRIBED BY THE OCCUPATIONAL
SAFETY AND HEALTH ADMINISTRATION (OSHA)
AND THE ENVIRONMENTAL SAFETY AGENCY(EPA), FOR THE HANDLING AND DISPOSAL OF
PRODUCTS CONTAINING ASBESTOS.
DIAGNOSIS AND TESTING
A road test and component inspection is recom-
mended to determine a clutch problem. During a
road test, drive the vehicle at normal speeds. Shift
the transmission through all gear ranges and observe
clutch action. If the clutch chatters, grabs, slips or
does not release properly, remove and inspect the
clutch components. If the problem is noise or hard
shifting, further diagnosis may be needed as the
transmission or another driveline component may be
at fault.
CLUTCH CONTAMINATION
Fluid contamination is a frequent cause of clutch
malfunctions. Oil, water or clutch fluid on the clutch
disc and pressure plate surfaces will cause chatter,
slip and grab. Inspect components for oil, hydraulic
fluid or water/road splash contamination.
Oil contamination indicates a leak at either the
rear main seal or transmission input shaft. Clutch
fluid leaks are usually from damaged slave cylinder
push rod seals. Heat buildup caused by slippage
between the pressure plate, disc and flywheel can
bake the oil residue onto the components. The glaze-
like residue ranges in color from amber to black.
Road splash contamination is dirt/water entering
the clutch housing due to loose bolts, housing cracks.
Driving through deep water puddles can force water/
road splash into the housing through such openings.
IMPROPER RELEASE OR CLUTCH ENGAGEMENT
Clutch release or engagement problems can be
caused by worn or damage clutch components. A
visual inspection of the release components will usu-
ally reveal the problem part.
Release problems can result in hard shifting and
noise. Look for leaks at the clutch cylinders and
interconnecting line and loose slave cylinder bolts.
Also worn/loose release fork, pivot stud, clutch disc,
pressure plate or release bearing.
Engagement problems can result in slip, chatter/
shudder and noisy operation. The causes may be
clutch disc contamination, wear, distortion or fly-
wheel damage. Visually inspect to determine the
actual cause of the problem.
CLUTCH MISALIGNMENT
Clutch components must be in proper alignment
with the crankshaft and transmission input shaft.
Misalignment caused by excessive runout or warpage
of any clutch component will cause grab, chatter and
improper clutch release.
Fig. 2 CLUTCH OPERATION
1 - FLYWHEEL
2 - PRESSURE PLATE FINGERS
3 - PIVOT POINT
4 - RELEASE BEARING PUSHED IN
5 - CLUTCH DISC ENGAGED
6 - CLUTCH DISC ENGAGED
7 - RELEASE BEARING
6 - 2 CLUTCHDR
CLUTCH (Continued)

(6) Install plastic clip securing hydraulic line to
the dash panel into the lower dash panel flange.
(7) Install plastic clip securing hydraulic line to
the dash panel onto the upper dash panel stud.
(8) Raise vehicle.
(9) Install slave cylinder and verify cylinder rod is
properly seated in release lever.
(10) Install and tighten slave cylinder nuts to 23
N´m (17 ft. lbs.).
(11) Ifnewclutch linkage is being installed, con-
nect the clutch hydraulic line to the clutch slave cyl-
inder.
CAUTION: Once the clutch hydraulic line is con-
nected to the slave cylinder, it should never be dis-
connected.
(12) Lower vehicle.
(13) Operate linkage several times to verify proper
operation.
CLUTCH PEDAL POSITION
SWITCH
DESCRIPTION
A clutch pedal position (interlock) switch is
mounted on the clutch master cylinder push rod (Fig.
22). The switch is actuated by clutch pedal move-
ment.
OPERATION
The clutch pedal position switch is used to prevent
starter motor engagement unless the clutch pedal is
depressed.
An input from this switch is also used to either
shut down and/or prevent operation of the speed con-
trol system when the clutch pedal is depressed.
The position switch is an integral part of the clutch
master cylinder push rod and is not serviced sepa-
rately.
DIAGNOSIS AND TESTING
(1) Locate clutch switch 2-wire electrical connector.
This will be the test point. This connector is attached
to pedal support bracket located under instrument
panel to left of clutch pedal (Fig. 23). Disconnect wir-
ing at this point.
(2) Check for switch continuity with an ohmmeter
while operating clutch pedal up and down. Continu-
ity should be broken and reapplied each time pedal is
pressed.
(3) If continuity is not present, or is always
present at any pedal position, replace switch. Switch
is not serviced separately. Replace clutch master
cylinder.
Fig. 22 LOCATION, CLUTCH PEDAL POSITION
SWITCH
1 - CLUTCH MASTER CYLINDER
2 - CLUTCH PEDAL POSITION SWITCH
Fig. 23 CLUTCH SWITCH TEST POINT
1 - PEDAL SUPPORT BRACKET
2 - ELECTRICAL CONNECTOR
6 - 14 CLUTCHDR
LINKAGE (Continued)

system is pressurized and uses a centrifugal water
pump to circulate coolant throughout the system.
5.9L, 5.9L Diesel, and 8.0L engines utilize an
ambient overflow bottle for coolant recovery/reserve.
The 3.7L and 4.7L engines utilize a pressurized
degas bottle for coolant deaeration and reserve. This
degas bottle has coolant flowing through it continu-
ously, supplied by a vent in the hot side radiator
tank and returning to the heater return hose.
An optional factory installed maximum duty cool-
ing package is available on most models. This pack-
age will provide additional cooling capacity for
vehicles used under extreme conditions such as
trailer towing in high ambient temperatures.
OPERATIONÐHOSE CLAMPS
The spring type hose clamp applies constant ten-
sion on a hose connection. To remove a spring type
hose clamp, only use constant tension clamp pliers
designed to compress the hose clamp.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐON-BOARD
DIAGNOSTICS (OBD)
COOLING SYSTEM RELATED DIAGNOSTICS
The Engine Control Module (ECM) has been pro-
grammed to monitor certain cooling system compo-
nents:
²If the engine has remained cool for too long a
period, such as with a stuck open thermostat, a Diag-
nostic Trouble Code (DTC) can be set.²If an open or shorted condition has developed in
the electronically controlled viscous fan clutch circuit,
a Diagnostic Trouble Code (DTC) can be set.
²If fan speed is not detected a DTC will be set.
²Coolant temperature sensor circuit problems can
set a DTC.
If the problem is sensed in a monitored circuit
often enough to indicated an actual problem, a DTC
is stored. The DTC will be stored in the ECM mem-
ory for eventual display to the service technician.
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ACCESSING DIAGNOSTIC TROUBLE CODES
To read DTC's and to obtain cooling system data,
(Refer to 25 - EMISSIONS CONTROL - DESCRIP-
TION).
ERASING TROUBLE CODES
After the problem has been repaired, use the
DRBIIItscan tool to erase a DTC. Refer to the
appropriate Powertrain Diagnostic Procedures ser-
vice information for operation of the DRBIIItscan
tool.
DIAGNOSIS AND TESTINGÐCOOLING SYSTEM
- TESTING FOR LEAKS
ULTRAVIOLET LIGHT METHOD
A leak detection additive is available through the
parts department that can be added to cooling sys-
tem. The additive is highly visible under ultraviolet
light (black light). Pour one ounce of additive into
cooling system. Place heater control unit in HEAT
position. Start and operate the engine until the radi-
ator upper hose is warm to the touch. Aim the com-
mercially available black light tool at the components
to be checked. If leaks are present, the black light
will cause the additive to glow a bright green color.
The black light can be used in conjunction with a
pressure tester to determine if any external leaks
exist (Fig. 5).
PRESSURE TESTER METHOD
The engine should be at normal operating temper-
ature. Recheck the system cold if the cause of coolant
loss is not located during the warm engine examina-
tion.
WARNING: HOT, PRESSURIZED COOLANT CAN
CAUSE INJURY BY SCALDING.
Carefully remove the radiator pressure cap from
the filler neck and check the coolant level. Push
down on the cap to disengage it from the stop tabs.
Wipe the inside of the filler neck and examine the
Fig. 4 Spring Clamp Size Location
1 - SPRING CLAMP SIZE LOCATION
DRCOOLING 7 - 5
COOLING (Continued)