GEAR RATIOS
The 545RFE gear ratios are:
OPERATION
The 45RFE/545RFE offers full electronic control of all automatic up and downshifts, and features real-time adaptive
closed-loop shift and pressure control. Electronic shift and torque converter clutch controls help protect the trans-
mission from damage due to high temperatures, which can occur under severeoperating conditions. By altering shift
schedules, line pressure, and converter clutch control, these controls reduce heat generation and increase trans-
mission cooling.
To help reduce efficiency-robbing parasitic losses, the transmissions includes a dual-stage transmission fluid pump
with electronic output pressure control. Under most driving conditions,pump output capacity greatly exceeds that
which is needed to keep the clutches applied. The 45RFE/545RFE pump-pressure control system monitors input
torque and adjusts the pump pressure accordingly. The primary stage of thepump works continuously; the second
stage is bypassed when demand is low. The control system also monitors input and output speed and, if incipient
clutch slip is observed, the pressure control solenoid duty cycle is varied, increasing pressure in proportion to
demand.
A high-travel torque converter damper assembly allows earlier torque converter clutch engagement to reduce slip-
page. Needle-type thrust bearings reduce internal friction. The 45RFE/545RFE is packaged in a one-piece die-cast
aluminum case. To reduce NVH, the case has high lateral, vertical and torsional stiffness. It is also designed to
maximize the benefit of the structural dust cover that connects the bottomof the bell housing to the engine bed-
plate, enhancing overall power train stiffness. Dual filters protect thepump and other components. A cooler return
filter is added to the customary main sump filter. Independent lubrication and cooler circuits assure ample pressure
for normal transmission operation even if the cooler is obstructed or the fluid cannot flow due to extremely low
temperatures.
The hydraulic control system design (without electronic assist) provides the transmission with PARK, REVERSE,
NEUTRAL, SECOND, and THIRD gears, based solely on driver shift lever selection. This design allows the vehicle
to be driven (in “limp-in” mode) in the event of a electronic control systemfailure, or a situation that the Transmis-
sion Control Module (TCM) recognizes as potentially damaging to the transmission.
The TCM also performs certain self-diagnostic functions and provides comprehensive information (sensor data,
DTC’s, etc.) which is helpful in proper diagnosis and repair. This information can be viewed with the DRB
scan
tool.
DIAGNOSIS AND TESTING
AUTOMATIC TRANSMISSION
CAUTION: Before attempting any repair on a RFE automatic transmission, check for Diagnostic Trouble
Codes with the scan tool.
Transmission malfunctions may be caused by these general conditions:
Poor engine performance
Improper adjustments
Hydraulic malfunctions
Mechanical malfunctions
Electronic malfunctions
Diagnosis of these problems should always begin by checking the easily accessible variables: fluid level and con-
dition, gearshift cable adjustment. Then perform a road test to determineif the problem has been corrected or if
more diagnosis is necessary. If the problem persists after the preliminary tests and corrections are completed,
hydraulic pressure checks should be performed.
PRELIMINARY
Two basic procedures are required. One procedure for vehicles that are drivable and an alternate procedure for
disabled vehicles (will not back up or move forward).
VEHICLE IS DRIVABLE
1. Check for transmission fault codes using scan tool.
2. Check fluid level and condition.
3. Adjust gearshift cable if complaint was based on delayed, erratic, or harsh shifts.
4. Road test and note how transmission upshifts, downshifts, and engages.
5. Perform hydraulic pressure test if shift problems were noted during roadtest.
6. Perform air-pressure test to check clutch operation.
VEHICLE IS DISABLED
1. Check fluid level and condition.
2. Check for broken or disconnected gearshift cable.
3. Check for cracked, leaking cooler lines, or loose or missing pressure-port plugs.
4. Raise and support vehicle on safety stands, start engine, shift transmission into gear, and note following:
a. If propeller shaft turns but wheels do not, problem is with differentialor axle shafts.
b. If propeller shaft does not turn and transmission is noisy, stop engine.Remove oil pan, and check for debris.
If pan is clear, remove transmission and check for damaged driveplate, converter, oil pump, or input shaft.
c. If propeller shaft does not turn and transmission is not noisy, perform hydraulic-pressure test to determine if
problem is hydraulic or mechanical.
ROAD TESTING
Before road testing, be sure the fluid level and control cable adjustmentshave been checked and adjusted if nec-
essary. Verify that all diagnostic trouble codes have been resolved.
Observe engine performance during the road test. A poorly tuned engine will not allow accurate analysis of trans-
mission operation.
Operate the transmission in all gear ranges. Check for shift variations and engine flare which indicates slippage.
Note if shifts are harsh, spongy, delayed, early, or if part throttle downshifts are sensitive.
Slippage indicated by engine flare, usually means clutch, overrunning clutch, or line pressure problems.
A slipping clutch can often be determined by comparing which internal units are applied in the various gear ranges.
The Clutch Application charts provide a basis for analyzing road test results.
45RFE CLUTCH APPLICATION CHART
line pressure reading should match the gauge reading within ±10 psi.
In order to access any other pressure tap locations,
the transmission oil pan must be removed, the pres-
sure port plugs removed and Valve Body Pressure Tap
Adapter 8258-A (2) installed. The extensions supplied
with Adapter 8258-A will allow the installation of pres-
sure gauges to the valve body.
Refer to the Pressure Tap Locations graphic for cor-
rect pressure tap location identification.
TEST PROCEDURE
All pressure readings should be taken with the transmission fluid level full, transmission oil at the normal operating
temperature, and the engine at 1500 rpm. Check the transmission for properoperation in each gear position that is
in question or if a specific element is in question, check the pressure readings in at least two gear positions that
employ that element. Refer to the Hydraulic Schematics at the rear of this section to determine the correct pres-
sures for each element in a given gear position.
NOTE: The 45RFE/545RFE utilizes closed loop control of pump line pressure. The pressure readings may
therefore vary greatly but should always follow line pressure.
Some common pressures that can be measured to evaluate pump and clutch performance are the upshift/downshift
pressures, garage shift pressures, and TCC pressure. The upshift/downshift pressure for all shifts are shown in
UPSHIFT PRESSURES and DOWNSHIFT PRESSURES . In-gear maximum pressure foreach gear position is
shown in IN-GEAR PRESSURES . The garageshift pressure when performing a N-R shift is 220 psi for 3.7L/4.7L
equipped vehicles and 250 psi for 5.7L equipped vehicles. The garage shiftpressure for the R-N shift is 120 psi.
The garage shift pressure for the N-1 shift is 135 psi for 3.7L/4.7L equipped vehicles and 165 psi for 5.7L equipped
vehicles. Torque converter lock-up pressure is 120 psi for 3.7L/4.7L equipped vehicles and 125 psi for 5.7L
equipped vehicles.
UPSHIFT PRESSURES
ENGINE 1-2 2-3 2prime-3 3-4 2prime-4 2-5 3-5 4-5
5.7L150 125 125 135 135 135 135 135
3.7L/4.7L120 120 120 120 120 120 120 130
DOWNSHIFT PRESSURES
ENGINE 5-4 5-3 5-2 4-3 4-
2prime3-2 3-
2prime2prime-1 2-1 3-1
5.7L135 135 135 135 135 135 135 135 135 135
3.7L/
4.7L120 120 120 120 120 120 120 120 120 120
IN-GEAR PRESSURES
ENGINE122prime345NEUTRALREVERSE
5.7L160 135 135 135 135 135 120 250
3.7L/4.7L135 120 120 120 120 120 120 220
AIR CHECKING TRANSMISSION CLUTCH OPERATION
Air-pressure testing can be used to check transmis-
sion clutch operation. The test can be conducted with
the transmission either in the vehicle or on the work
bench, as a final check.
Air-pressure testing requires that the oil pan and valve
body be removed from the transmission. The clutch
apply passages are shown in the Air Pressure Test
Passages graphic.
NOTE: The air supply which is used must be free
ofmoistureanddirt.Useapressureof30psito
test clutch operation.
Apply air pressure at each port. If the clutch is func-
tioning, 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.
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.
1 - LOW REVERSE CLUTCH
2 - 4TH CLUTCH
3 - 2ND CLUTCH
4-OVERDRIVECLUTCH
5 - UNDERDRIVE CLUTCH
6 - REVERSE CLUTCH
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 during factory fill or fill after repair. Converter housing leaks have
several potential sources. Through careful observation, a leak source can be identified before removing the trans-
mission for repair. Torque converter seal leaks tend to move along the drive hub and onto the rear of the converter.
Pump cover seal leaks tend to run down the cover and the inside surface of thebellhousing.
Some leaks, or suspected leaks, may be particularly difficult to locate. If necessary, a Mopar
approved dye should
be used to locate and confirm a leak.
TORQUE CONVERTER LEAK POINTS
Possible sources of converter leaks are:
1. Leaks at the weld joint around the outside diameter
weld.
2. Leaks at the converter hub weld.
In most cases, a torque converter which is wet from
transmission fluid indicates a leak at one of these
areas.
STANDARD PROCEDURE - ALUMINUM THREAD REPAIR
DamagedorwornthreadsinthealuminumtransmissioncaseandvalvebodycanberepairedbytheuseofHeli-
Coils™, or equivalent. This repair consists of drilling out the worn-out damaged threads. Then tap the hole with a
special Heli-Coil™ tap, or equivalent, and installing a Heli-Coil™ insert, or equivalent, into the hole. This brings the
hole back to its original thread size.
Heli-Coil™, 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 (1) to transmission (3) struc-
tural dust cover (2).
15. Disengage the line pressure sensor connector
from the line pressure sensor (2).
16. Disconnect gearshift cable (1) from transmission
manual valve lever (3).
17. Disconnect the transmission vent hose from the
transmission.
18. Support rear of engine with safety stand or jack.
19. Raise transmission slightly with service jack to
relieve load on crossmember and supports.
20. Remove bolts securing rear support and cushion
to transmission and crossmember.
21. Remove transfer case, if necessary.
22. Disconnect transmission fluid cooler lines at trans-
mission fittings and clips.
23. Remove all remaining converter housing bolts.
24. Carefully work transmission and torque converter
assembly rearward off engine block dowels.
25. Hold torque converter in place during transmission
removal.
26. Lower transmission (2) and remove assembly from under the vehicle.
27. To remove torque converter, carefully slide torque converter out of the transmission.
INSTALLATION
1. Check torque converter hub and hub drive flats for
sharp edges burrs, scratches, or nicks. Polish the
hub and flats with 320/400 grit paper and crocus
cloth if necessary. Verify that the converter hub
o-ring is properly installed and is free of any debris.
The hub must be smooth to avoid damaging pump
seal at installation.
2. If a replacement transmission is being installed,
transfer any components necessary, such as the
manual shift lever and shift cable bracket, from the
original transmission onto the replacement trans-
mission.
3. Lubricate oil pump seal lip with transmission fluid.
4. Align converter and oil pump.
5. Carefully insert converter in oil pump. Then rotate
converter back and forth until fully seated in pump
gears.
6. Check converter seating with steel scale (1) and
straightedge (2). Surface of converter lugs should
be at least 13mm (1/2 in.) to rear of straightedge when converter is fully seated.
7. Temporarily secure converter with C-clamp.
8. Position transmission on jack and secure it with
chains.
9. Check condition of converter driveplate. Replace
the plate if cracked, distorted or damaged.Also be
sure transmission dowel pins are seated in
engine block and protrude far enough to hold
transmission in alignment.
10. Apply a light coating of Mopar
High Temp
Grease to the torque converter hub pocket in the
rear pocket of the engine’s crankshaft.
11. Raise transmission (2) and align the torque con-
verter with the drive plate and transmission con-
verter housing with the engine block.
12. Move transmission forward. Then raise, lower or
tilt transmission to align the converter housing
with engine block dowels.
13. Carefully work transmission forward and over
engine block dowels until converter hub is seated
in crankshaft. Verify that no wires, or the transmis-
sion vent hose, have become trapped between
theengineblockandthetransmission.
14. Install two bolts to attach the transmission to the
engine.
15. Install remaining torque converter housing to
engine bolts. Tighten to 68 Nꞏm (50 ft.lbs.).
16. Install transfer case, if equipped. Tighten transfer
case nuts to 35 Nꞏm (26 ft.lbs.).
17. Install rear support to transmission. Tighten bolts
to 47 Nꞏm (35 ft.lbs.).
18. Lower transmission onto crossmember and install bolts attaching transmission mount to crossmember. Tighten
clevis bracket to crossmember bolts to 47 Nꞏm (35 ft.lbs.). Tighten the clevis bracket to rear support bolt to 68
Nꞏm (50 ft.lbs.).
19. Remove engine support fixture.
20. Connect gearshift cable to transmission.
21. Connect wires to solenoid and pressure switch assembly (2) connector.
22. Connect wires to input speed sensor (2).
23. Connect wires to output speed sensor (2).
24. Connect wires to line pressure sensor (2). Be
sure transmission harnesses are properly routed.