2003 DODGE RAM Transmission fluid fill

OPERATION
NOTE: Refer to the Hydraulic Schematics for a
visual aid in determining valve location, operation
and design.
CHECK BALLS
CHECK BALL
NUMBERDESCRIPTION
1 Allows either the manual valve to put line pressure on the 1-2 governor plug or the KD Valve to
put WOT line pressure on the 1-2 governor plug.
3 Allows either the Reverse circuit or the 3rd gear circuit to pressurize the front clutch.
4 Allows either the Manual Low circuit from the Manual Valve or the Reverse from the Manual
Valve circuit to pressurize the rear servo.
5 Directs line pressure to the spring end of the 2-3 shift valve in either Manual Low or Manual
2nd, forcing the downshift to 2nd gear regardless of governor pressure.
6 Provides a by-pass around the front servo orifice so that the servo can release quickly.
7 Provides a by-pass around the rear clutch orifice so that the clutch can release quickly.
8 Directs reverse line pressure through an orifice to the throttle valve eliminating the extra
leakage and insuring that Reverse line pressure pressure will be sufficient.
9 Provides a by-pass around the rear servo orifice so that the servo can release quickly.
10 Allows the lockup clutch to used at WOT in 3rd gear by putting line pressure from the 3-4
Timing Valve on the interlock area of the 2-3 shift valve, thereby preventing a 3rd gear Lock-up
to 2nd gear kickdown.
REGULATOR VALVE
The pressure regulator valve is needed to control
the hydraulic pressure within the system and reduce
the amount of heat produced in the fluid. The pres-
sure regulator valve is located in the valve body near
the manual valve. The pressure regulator valve train
controls the maximum pressure in the lines by
metering the dumping of fluid back into the sump.
Regulated pressure is referred to as ªline pressure.º
The regulator valve (Fig. 255) has a spring on one
end that pushes the valve to the left. This closes a
dump (vent) that is used to lower pressure. The clos-
ing of the dump will cause the oil pressure to
increase. Oil pressure on the opposite end of the
valve pushes the valve to the right, opening the
dump and lowering oil pressure. The result is spring
pressure working against oil pressure to maintain
the oil at specific pressures. With the engine run-
ning, fluid flows from the pump to the pressure reg-
ulator valve, manual valve, and the interconnected
circuits. As fluid is sent through passages to the reg-
ulator valve, the pressure pushes the valve to the
right against the large spring. It is also sent to the
reaction areas on the left side of the throttle pressure
plug and the line pressure plug. With the gear selec-tor in the PARK position, fluid recirculates through
the regulator and manual valves back to the sump.
Meanwhile, the torque converter is filled slowly. In
all other gear positions (Fig. 256), fluid flows
between two right side lands to the switch valve and
torque converter. At low pump speeds, the flow is
controlled by the pressure valve groove to reduce
pressure to the torque converter. After the torque
converter and switch valve fill with fluid, the switch
valve becomes the controlling metering device for
torque converter pressure. The regulator valve then
begins to control the line pressure for the other
transmission circuits. The balance of the fluid pres-
sure pushing the valve to the right and the spring
pressure pushing to the left determines the size of
the metering passage at land #2 (land #1 being at
the far right of the valve in the diagram). As fluid
leaks past the land, it moves into a groove connected
to the filter or sump. As the land meters the fluid to
the sump, it causes the pressure to reduce and the
spring decreases the size of the metering passage.
When the size of the metering passage is reduced,
the pressure rises again and the size of the land is
increased again. Pressure is regulated by this con-
stant balance of hydraulic and spring pressure.
21 - 450 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)

Check the two separator plates for distortion or
damage of any kind. Inspect the upper housing,
lower housing, 3-4 accumulator housing, and transfer
plate carefully. Be sure all fluid passages are clean
and clear. Check condition of the upper housing and
transfer plate check balls as well. The check balls
and ball seats must not be worn or damaged.
Trial fit each valve and plug in its bore to check
freedom of operation. When clean and dry, the valves
and plugs should drop freely into the bores.
Valve body bores do not change dimensionally with
use. If the valve body functioned correctly when new,
it will continue to operate properly after cleaning and
inspection. It should not be necessary to replace a
valve body assembly unless it is damaged in han-
dling.
The only serviceable valve body components are
listed below. The remaining valve body components
are serviced only as part of a complete valve body
assembly. Serviceable parts are:
²dual solenoid and harness assembly
²solenoid gasket
²solenoid case connector O-rings and shoulder
bolt
²switch valve and spring
²pressure adjusting screw and bracket assembly
²throttle lever
²manual lever and shaft seal
²throttle lever shaft seal, washer, and E-clip
²fluid filter and screws
²detent ball and spring
²valve body screws
²governor pressure solenoid
²governor pressure sensor and retaining clip
²park lock rod and E-clipASSEMBLY
CAUTION: Do not force valves or plugs into place
during reassembly. If the valve body bores, valves
and plugs are free of distortion or burrs, the valve
body components should all slide into place easily.
In addition, do not overtighten the transfer plate
and valve body screws during reassembly. Over-
tightening can distort the housings resulting in
valve sticking, cross leakage and unsatisfactory
operation. Tighten valve body screws to recom-
mended torque only.
LOWER HOUSING
(1) Lubricate valves, springs, and the housing
valve and plug bores with clean transmission fluid
(Fig. 307).
(2) Install 3-4 timing valve spring and valve in
lower housing.
(3) Install 3-4 quick fill valve in lower housing.
(4) Install 3-4 quick fill valve spring and plug in
housing.
(5) Install timing valve end plate. Tighten end
plate screws to 4 N´m (35 in. lbs.) torque.
DRAUTOMATIC TRANSMISSION - 48RE 21 - 477
VALVE BODY (Continued)

(20)Install solenoid assembly and gasket. Tighten
solenoid attaching screws to 8 N´m (72 in. lbs.) torque.
(21) Verify that solenoid wire harness is properly
routed (Fig. 328). Solenoid harness must be clear of
manual lever and park rod and not be pinched
between accumulator housing and cover.
GOVERNOR BODY, SENSOR AND SOLENOID
(1) Turn valve body assembly over so accumulator
side of transfer plate is facing down.
(2) Install new O-rings on governor pressure sole-
noid and sensor.
(3) Lubricate solenoid and sensor O-rings with
clean transmission fluid.
(4)
Install governor pressure sensor in governor body.
(5)Install governor pressure solenoid in governor
body. Push solenoid in until it snaps into place in body.
(6)Position governor body gasket on transfer plate.
(7) Install retainer plate on governor body and
around solenoid. Be sure solenoid connector is posi-
tioned in retainer cutout.
(8) Align screw holes in governor body and trans-
fer plate. Then install and tighten governor body
screws to 4 N´m (35 in. lbs.) torque.
(9) Connect harness wires to governor pressure
solenoid and governor pressure sensor.
(10) Install fluid filter and pan.
(11) Lower vehicle.
(12) Fill transmission with recommended fluid and
road test vehicle to verify repair.
INSTALLATION
(1) Check condition of O-ring seals on valve body
harness connector (Fig. 329). Replace seals on con-
nector body if cut or worn.
(2)
Check condition of manual lever shaft seal in
transmission case. Replace seal if lip is cut or worn.
Install new seal with 15/16 deep well socket (Fig. 330).
(3) Check condition of seals on accumulator piston.
Install new piston seals, if necessary.
(4) Verify that transmission range sensor isNOT
installed. Valve body cannot be installed with sensor
in place.
(5) Place valve body manual lever in low (1 posi-
tion) so ball on park lock rod will be easier to install
in sprag.
(6) Lubricate shaft of manual lever with petroleum
jelly. This will ease inserting shaft through seal in
case.
(7) Lubricate seal rings on valve body harness con-
nector with petroleum jelly.
(8) Position valve body in case and work end of
park lock rod into and through pawl sprag. Turn pro-
peller shaft to align sprag and park lock teeth if nec-
essary. The rod will click as it enters pawl. Move rod
to check engagement.
CAUTION: It is possible for the park rod to displace
into a cavity just above the pawl sprag during
installation. Make sure the rod is actually engaged
in the pawl and has not displaced into this cavity.
(9) Install accumulator spring and piston into case.
Then swing valve body over piston and outer spring
to hold it in place.
(10) Align accumulator piston and outer spring,
manual lever shaft and electrical connector in case.
(11) Then seat valve body in case and install one
or two bolts to hold valve body in place.
(12) Tighten valve body bolts alternately and
evenly to 11 N´m (100 in. lbs.) torque.
(13) Install new fluid filter on valve body. Tighten
filter screws to 4 N´m (35 in. lbs.) torque.
(14) Install throttle and gearshift levers on valve
body manual lever shaft.
Fig. 329 Valve Body Harness Connector O-Ring Seal
1 - CONNECTOR O-RINGS
2 - VALVE BODY HARNESS CONNECTOR
3 - HARNESS
Fig. 328 Solenoid Harness Routing
1 - OVERDRIVE/CONVERTER SOLENOID WIRE HARNESS
2 - 3-4 ACCUMULATOR COVER PLATE
21 - 486 AUTOMATIC TRANSMISSION - 48REDR
VALVE BODY (Continued)

(15) Check and adjust front and rear bands if nec-
essary.
(16) Connect solenoid case connector wires.
(17) Install the transmission range sensor.
(18) Install oil pan and new gasket. Tighten pan
bolts to 17 N´m (13 ft. lbs.) torque.
(19) Lower vehicle and fill transmission with
MopartATF +4, Automatic Transmission fluid.
(20) Check and adjust gearshift and throttle valve
cables, if necessary.
ADJUSTMENTS - VALVE BODY
CONTROL PRESSURE ADJUSTMENTS
There are two control pressure adjustments on the
valve body;
²Line Pressure
²Throttle Pressure
Line and throttle pressures are interdependent
because each affects shift quality and timing. As a
result, both adjustments must be performed properly
and in the correct sequence. Adjust line pressure first
and throttle pressure last.
LINE PRESSURE ADJUSTMENT
Measure distance from the valve body to the inner
edge of the adjusting screw with an accurate steel
scale (Fig. 331).
Distance should be 33.4 mm (1-5/16 in.).
If adjustment is required, turn the adjusting screw
in, or out, to obtain required distance setting.
NOTE: The 33.4 mm (1-5/16 in.) setting is an
approximate setting. Manufacturing tolerances may
make it necessary to vary from this dimension to
obtain desired pressure.
One complete turn of the adjusting screw changes
line pressure approximately 1-2/3 psi (9 kPa).Turning the adjusting screw counterclockwise
increases pressure while turning the screw clockwise
decreases pressure.
THROTTLE PRESSURE ADJUSTMENT
Insert Gauge Tool C-3763 between the throttle
lever cam and the kickdown valve stem (Fig. 332).
Push the gauge tool inward to compress the kick-
down valve against the spring and bottom the throt-
tle valve.
Maintain pressure against kickdown valve spring.
Turn throttle lever stop screw until the screw head
touches throttle lever tang and the throttle lever cam
touches gauge tool.
NOTE: The kickdown valve spring must be fully
compressed and the kickdown valve completely
bottomed to obtain correct adjustment.
Fig. 330 Manual Lever Shaft Seal
1 - 15/1688SOCKET
2 - SEAL
Fig. 331 Line Pressure Adjustment
1 - WRENCH
2 - 1±5/16 INCH
Fig. 332 Throttle Pressure Adjustment
1 - HEX WRENCH (IN THROTTLE LEVER ADJUSTING SCREW)
2 - SPECIAL TOOL C-3763 (POSITIONED BETWEEN THROTTLE
LEVER AND KICKDOWN VALVE)
DRAUTOMATIC TRANSMISSION - 48RE 21 - 487
VALVE BODY (Continued)

AUTOMATIC TRANSMISSION - 45RFE/545RFE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 45RFE/545RFE
DESCRIPTION........................489
OPERATION..........................490
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION.....................491
DIAGNOSIS AND TESTING - PRELIMINARY. . 491
DIAGNOSIS AND TESTING - ROAD
TESTING...........................491
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST....................493
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH OPERATION....494
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK................495
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR.....................495
REMOVAL............................495
DISASSEMBLY........................497
CLEANING...........................502
INSPECTION.........................503
ASSEMBLY...........................503
INSTALLATION........................510
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS.............513
SPECIFICATIONS
TRANSMISSION.....................534
SPECIAL TOOLS
RFE TRANSMISSION.................535
4C RETAINER/BULKHEAD
DISASSEMBLY........................538
ASSEMBLY...........................538
ADAPTER HOUSING SEAL
REMOVAL............................539
INSTALLATION........................539
BRAKE TRANSMISSION SHIFT INTERLOCK
SYSTEM
DESCRIPTION........................540
OPERATION..........................540
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK......540
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK...................540
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL.............541
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID.......................541DIAGNOSIS AND TESTING - FLUID
CONTAMINATION....................541
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK............................542
STANDARD PROCEDURE - FLUID AND
FILTER REPLACEMENT...............542
STANDARD PROCEDURE - TRANSMISSION
FILL...............................544
GEARSHIFT CABLE
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE.............................544
REMOVAL............................544
INSTALLATION........................545
ADJUSTMENTS
GEARSHIFT CABLE..................546
HOLDING CLUTCHES
DESCRIPTION........................546
OPERATION..........................546
INPUT CLUTCH ASSEMBLY
DESCRIPTION........................549
OPERATION..........................549
DISASSEMBLY........................550
ASSEMBLY...........................552
INPUT SPEED SENSOR
DESCRIPTION........................558
OPERATION..........................558
REMOVAL............................559
INSTALLATION........................559
LINE PRESSURE (LP) SENSOR
DESCRIPTION........................559
OPERATION..........................559
REMOVAL............................559
INSTALLATION........................560
LOW/REVERSE CLUTCH
DISASSEMBLY........................560
CLEANING...........................561
INSPECTION.........................561
ASSEMBLY...........................561
OIL PUMP
DESCRIPTION........................562
OPERATION..........................562
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................563
DISASSEMBLY........................564
CLEANING...........................566
INSPECTION.........................566
ASSEMBLY...........................566
21 - 488 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR

NOTE: The air supply which is used must be free of
moisture and dirt. Use a pressure of 30 psi to test
clutch operation.
Apply air pressure at each port. If the clutch is
functioning, a soft thump will be heard as the clutch
is applied. The clutch application can also be felt by
touching the appropriate element while applying air
pressure. As the air pressure is released, the clutch
should also release.
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK
When diagnosing converter housing fluid leaks,
two items must be established before repair.
(1) Verify that a leak condition actually exists.
(2) Determined the true source of the leak.
Some suspected converter housing fluid leaks may not
be leaks at all. They may only be the result of residual
fluid in the converter housing, or excess fluid spilled dur-
ing factory fill or fill after repair. Converter housing
leaks have several potential sources. Through careful
observation, a leak source can be identified before remov-
ing the transmission for repair. Torque converter seal
leaks tend to move along the drive hub and onto the rear
of the converter. Pump cover seal tend to run down the
cover and the inside surface of the bellhousing.
Some leaks, or suspected leaks, may be particu-
larly difficult to locate. If necessary, a Mopart
approved dye may be used to locate a leak.
TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
(1) Leaks at the weld joint around the outside
diameter weld (Fig. 7).
(2) Leaks at the converter hub weld (Fig. 7).
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR
Damaged or worn threads in the aluminum trans-
mission case and valve body can be repaired by the
use of Heli-CoilsŸ, or equivalent. This repair con-
sists of drilling out the worn-out damaged threads.
Then tap the hole with a special Heli-CoilŸ tap, or
equivalent, and installing a Heli-CoilŸ insert, or
equivalent, into the hole. This brings the hole back to
its original thread size.
Heli-CoilŸ, or equivalent, tools and inserts are
readily available from most automotive parts suppliers.
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise and support the vehicle
(3) Remove any necessary skid plates. (Refer to 13
- FRAMES & BUMPERS/FRAME/TRANSFER CASE
SKID PLATE - REMOVAL)(4) Mark propeller shaft and axle companion
flanges for assembly alignment.
(5) Remove the rear propeller shaft
(6) Remove the front propeller shaft, if necessary.
(7)
Remove the engine to transmission collar (Fig. 8).
(8) Remove the exhaust support bracket from the
rear of the transmission.
Fig. 7 Torque Converter Assembly
1 - TURBINE ASSEMBLY
2-STATOR
3 - CONVERTER HUB
4 - O-RING
5 - IMPELLER ASSEMBLY
6 - CONVERTER CLUTCH PISTON
7 - TURBINE HUB
Fig. 8 Transmission Collar
1 - ENGINE
2 - ENGINE TO TRANSMISSION COLLAR
3 - TRANSMISSION
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 495
AUTOMATIC TRANSMISSION - 45RFE/545RFE (Continued)

(27) Install the engine collar (Fig. 59) onto the
transmission and the engine. Tighten the bolts to 54
N´m (40 ft.lbs.).(28) Align and connect propeller shaft(s).
(29) Adjust gearshift cable if necessary.
(30) Install any skid plates removed previously.
(Refer to 13 - FRAMES & BUMPERS/FRAME/
TRANSFER CASE SKID PLATE - INSTALLATION)
(31) Lower vehicle.
(32) Fill transmission with MopartATF +4, Auto-
matic Transmission Fluid.
Fig. 59 Transmission Collar
1 - ENGINE
2 - ENGINE TO TRANSMISSION COLLAR
3 - TRANSMISSION
21 - 512 AUTOMATIC TRANSMISSION - 45RFE/545RFEDR
AUTOMATIC TRANSMISSION - 45RFE/545RFE (Continued)

BTSI FUNCTION CHECK
(1) Verify removal of ignition key allowed in PARK
position only.
(2) When the shift lever is in PARK, the ignition
key cylinder should rotate freely from off to lock.
When the shifter is in any other position, the ignition
key should not rotate from off to lock.
(3) Shifting out of PARK should be possible when
the ignition key cylinder is in the off position.
(4) Shifting out of PARK should not be possible
while applying normal force, and ignition key cylin-
der is in the run or start positions, unless the foot
brake pedal is depressed approximately 1/2 inch
(12mm).
(5) Shifting out of PARK should not be possible
when the ignition key cylinder is in the accessory or
lock position.
(6) Shifting between any gear and NEUTRAL, or
PARK, may be done without depressing foot brake
with ignition switch in run or start positions.
(7) Engine starts must be possible with shifter
lever in PARK or NEUTRAL positions only. Engine
starts must not be possible in any position other than
PARK or NEUTRAL.
(8) With shifter lever in the:
²PARK position - Apply upward force on the shift
arm and remove pressure. Engine starts must be
possible.
²PARK position - Apply downward force on the
shift arm and remove pressure. Engine starts must
be possible.
²NEUTRAL position - Normal position. Engine
starts must be possible.²NEUTRAL position - Engine running and brakes
applied, apply upward force on the shift arm. Trans-
mission shall not be able to shift from neutral to
reverse.
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL
A low fluid level allows the pump to take in air
along with the fluid. Air in the fluid will cause fluid
pressures to be low and develop slower than normal.
If the transmission is overfilled, the gears churn the
fluid into foam. This aerates the fluid and causing
the same conditions occurring with a low level. In
either case, air bubbles cause fluid overheating, oxi-
dation and varnish buildup which interferes with
valve and clutch operation. Foaming also causes fluid
expansion which can result in fluid overflow from the
transmission vent or fill tube. Fluid overflow can eas-
ily be mistaken for a leak if inspection is not careful.
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID
Burnt, discolored fluid is a result of overheating
which has three primary causes.
(1) Internal clutch slippage, usually caused by low
line pressure, inadequate clutch apply pressure, or
clutch seal failure.
(2) A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a faulty or improperly installed
drainback valve, a damaged main cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
(3) Heavy duty operation with a vehicle not prop-
erly equipped for this type of operation. Trailer tow-
ing or similar high load operation will overheat the
transmission fluid if the vehicle is improperly
equipped. Such vehicles should have an auxiliary
transmission fluid cooler, a heavy duty cooling sys-
tem, and the engine/axle ratio combination needed to
handle heavy loads.
DIAGNOSIS AND TESTING - FLUID
CONTAMINATION
Transmission fluid contamination is generally a
result of:
²adding incorrect fluid
²failure to clean dipstick and fill tube when
checking level
²engine coolant entering the fluid
Fig. 65 Brake Transmission Interlock Mechanism
1 - STEERING COLUMN
2 - GEARSHIFT CABLE
3 - GEARSHIFT CABLE LOCK TAB
4 - BTSI SOLENOID LOCK TAB
5 - BTSI CONNECTOR
DRAUTOMATIC TRANSMISSION - 45RFE/545RFE 21 - 541
BRAKE TRANSMISSION SHIFT INTERLOCK SYSTEM (Continued)