7.CHECK IF THE DTC P0871 ALSO SET
With the scan tool, check Transmission DTCs.
Is the DTC P0871 also present?
Ye s>>
Refer to the Transmission category and perform the appropriate symptom.
No>>
Go To 8
8.CHECK IF THE DTC SET IN PARK, REVERSE OR NEUTRAL
With the scan tool, check the DTC EVENT DATA for P0988.
NOTE: Make sure to record all DTC EVENT DATA stored in the scan tool for future reference in this test
procedure.
Does the DTC EVENT DATA show the DTC set in Park, Neutral, or Reverse for P0988?
Ye s>>
Go To 13
No>>
Go To 9
9.CHECK IF THE DTC EVENT DATA READS CLOSED
With the scan tool, check the DTC EVENT DATA for P0988.
NOTE: Make sure to record all DTC EVENT DATA stored in the scan tool for future reference in this test
procedure.
Does the DTC EVENT DATA show the 4C Pressure Switch reading CLOSED?
Ye s>>
Go To 11
No>>
Go To 10
10.CHECK THE PRIMARY OIL FILTER SEAL
In the DTC EVENT DATA recorded earlier,compare the Line Pressure and the Desired Line Pressure.
Is the Line Pressure less than 40 psi, and significantly below the Desired Line Pressure?
Ye s>>
Repair as necessary to correct low line pressure. Check fluid level and adjustasnecessary.Iffluidlevel
is OK, check the Primary Oil Filter seal for a split, crack, or improperly installed. If the filter and seal are
OK, check the Main Regulator Valve in the Oil Pump. Refer to the Service Information for the above
procedures.
Perform 45RFE/545RFE TRANSMISSION VERIFICATION TEST - VER 1. (Refer to 21- TRANSMIS-
SION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
No>>
Go To 15
11 .CHECK THE PCM AND WIRING
Turn the ignition off to the lock position.
Remove the Ignition Switch Feed fuse from the TIPM.
CAUTION: Removal of the Ignition Switch Feed fuse from the TIPM will prevent the vehicle from being
startedingear.
WARNING: The Ignition Switch Feed fuse must be removed from the TIPM. Failure to do so can result in
personal injury or death.
Install the Transmission Simulator, Miller tool #8333.
Ignition on, engine not running.
With the Transmission Simulator, turn the Pressure Switch selector switchtothe4Cposition.
P1736-GEAR RATIO ERROR IN 2ND PRIME
For a complete wiring diagramRefer to Section 8W.
When Monitored:
Continuously with the ignition on, engine running, with the transmissionin gear.
Set Condition:
If the ratio of the Input RPM to the Output RPM does not match the current gearratio. This DTC can take up
to five minutes of problem identification before illuminating the MIL
Possible Causes
RELATED DTC’S PRESENT
INPUT SPEED SENSOR OR WIRING
LOW FLUID LEVEL
CRACKED OR MIS-INSTALLED PRIMARY OIL FILTER OR SEAL
WORN SOLENOID SWITCH VALVE OR PLUGS
STUCK OR STICKING MAIN REGULATOR VALVE
BURNED UD OR 4C CLUTCH
CUT 4C OR UD PISTON SEAL
BROKEN 4C PISTON CASTING
BROKEN OR MISSING 4C BLEED ORIFICE
BROKEN OR MISSING UD BLEED ORIFICE
CUT 4C OR UD ACCUMULATOR PISTON SEAL
CRACKED 4C OR UD ACCUMULATOR PISTON
EXTRA CHECK BALL IN PASSAGE DOWNSTREAM OF #7 CHECK BALL POCKET
TRANSMISSION SOLENOID/TRS ASSEMBLY
BROKEN WELD - REACTION CARRIER TO REVERSE SUN GEAR
MISSING TEETH ON INPUT CLUTCH HUB TONE WHEEL
Always perform the 45RFE/545RFE Pre-Diagnostic Troubleshooting Procedure before proceeding. (Refer to
21 - TRANSMISSION/TRANSAXLE/AUTOMATIC - 45RFE/545RFE - STANDARD PROCEDURE)
Theory of Operation
The transmission system uses two speed sensors, one to measure input RPM and one to measure output RPM.
These inputs are essential for proper transmission operation. Therefore, the integrity of this data is verified through
the following checks:
1) When in gear, if the gear ratio does not compare to a known gear ratio, the corresponding in-gear trouble code
is set (DTCs P0731-36).
2) An excessive change in input or output speeds indicating signal intermittent which may result in the DTCs P0715
and/or P0720 to set.
3) If the common speed sensor ground circuit is lost, both sensor inputs will read the signal from the input speed
sensor at idle in neutral. Since the input speed sensor reads 60 teeth from the input clutch hub and the output
speed sensor reads 30 teeth from the park gear, the result is an apparent speed ratio of 1:2 and may cause the
DTC P1794 to set when at a stop.
page page
AUTOMATIC TRANSMISSION - 45RFE/545RFE -
SERVICE INFORMATION
DESCRIPTION ............................... 844
OPERATION ................................. 845
DIAGNOSIS AND TESTING
AUTOMATIC TRANSMISSION ............... 845
PRELIMINARY ............................. 846
ROAD TESTING ........................... 846
HYDRAULIC PRESSURE TEST............. 847
AIR CHECKING TRANSMISSION CLUTCH
OPERATION............................... 850
CONVERTER HOUSING FLUID LEAK ....... 850
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR .......................... 851
REMOVAL ................................... 851
DISASSEMBLY .............................. 854
CLEANING .................................. 860
INSPECTION ................................ 861
ASSEMBLY .................................. 861
INSTALLATION .............................. 871
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS ................. 874
SPECIFICATIONS
TRANSMISSION ........................... 896
SPECIAL TOOLS
AUTOMATIC TRANSMISSION - RFE ......... 898
RETAINER/BULKHEAD-4C
DISASSEMBLY .............................. 901
ASSEMBLY .................................. 903
SEAL-ADAPTER HOUSING
REMOVAL ................................... 906
INSTALLATION .............................. 906
SYSTEM-BRAKE TRANSMISSION SHIFT
INTERLOCK
DESCRIPTION ............................... 907
OPERATION ................................. 907
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK ......... 907
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK ......................... 907
FLUID AND FILTER
DIAGNOSIS AND TESTING
EFFECTS OF INCORRECT FLUID LEVEL.... 909
CAUSES OF BURNT FLUID ................. 909
FLUID CONTAMINATION ................... 909
STANDARD PROCEDURE
FLUID LEVEL CHECK . ..................... 909
FLUID AND FILTER REPLACEMENT ......... 911
TRANSMISSION FILL ...................... 912CABLE-GEARSHIFT
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE .................................... 913
REMOVAL ................................... 913
INSTALLATION .............................. 914
ADJUSTMENTS - GEARSHIFT CABLE ......... 915
CLUTCHES-HOLDING
DESCRIPTION ............................... 916
OPERATION ................................. 917
ASSEMBLY-INPUT CLUTCH
DESCRIPTION ............................... 918
OPERATION ................................. 920
DISASSEMBLY .............................. 920
ASSEMBLY .................................. 925
SENSOR-INPUT SPEED
DESCRIPTION ............................... 932
OPERATION ................................. 932
REMOVAL ................................... 932
INSTALLATION .............................. 933
SENSOR-LINE PRESSURE
DESCRIPTION ............................... 934
OPERATION ................................. 934
REMOVAL ................................... 934
INSTALLATION .............................. 935
CLUTCH-LOW/REVERSE
DISASSEMBLY .............................. 936
CLEANING .................................. 937
INSPECTION . . .............................. 937
ASSEMBLY .................................. 938
PUMP-OIL
DESCRIPTION ............................... 940
OPERATION ................................. 942
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK .......................... 942
DISASSEMBLY .............................. 943
CLEANING .................................. 945
INSPECTION . . .............................. 946
ASSEMBLY .................................. 946
SEAL-OIL PUMP FRONT
REMOVAL ................................... 950
INSTALLATION .............................. 950
SENSOR-OUTPUT SPEED
DESCRIPTION ............................... 951
OPERATION ................................. 951
REMOVAL ................................... 951
INSTALLATION .............................. 952
SWITCH-TOW/HAUL OVERDRIVE
DESCRIPTION ............................... 953
OPERATION ................................. 953
REMOVAL ................................... 953
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
FLUID AND FILTER
DIAGNOSIS AND TESTING
EFFECTS OF INCORRECT FLUID LEVEL
Alowfluidlevelallowsthepumptotakeinairalongwiththefluid.Airinthe fluid will cause fluid pressures to be
low and develop slower than normal. If the transmission is overfilled, thegears churn the fluid into foam. This aer-
ates the fluid and causing the same conditions occurring with a low level. In either case, air bubbles cause fluid
overheating, oxidation, and varnish buildup which interferes with valveand clutch operation. Foaming also causes
fluid expansion which can result in fluid overflow from the transmission vent or fill tube. Fluid overflow can easily be
mistaken for a leak if inspection is not careful.
CAUSES OF BURNT FLUID
Burnt, discolored fluid is a result of overheating which has three primarycauses.
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 usually the result of a
faulty or improperly installed drainback valve, a damaged oil cooler, or severe restrictions in the coolers and lines
caused by debris or kinked lines.
3. Heavy duty operation with a vehicle not properly equipped for this type of operation. Trailer towing 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 system,and the engine/axle ratio combination
needed to handle heavy loads.
FLUID CONTAMINATION
Transmission fluid contamination is generally a result of:
adding incorrect fluid
failure to clean dipstick and fill tube when checking level
engine coolant entering the fluid
internal failure that generates debris
overheat that generates sludge (fluid breakdown)
failure to replace contaminated converter after repair
The use of non-recommended fluids can result in transmission failure. Theusual results are erratic shifts, slippage,
abnormal wear and eventual failure due to fluid breakdown and sludge formation. Avoid this condition by using rec-
ommended fluids only.
The dipstick cap and fill tube should be wiped clean before checking fluid level. Dirt, grease and other foreign mate-
rial on the cap and tube could fall into the tube if not removed beforehand. Take the time to wipe the cap and tube
clean before withdrawing the dipstick.
Engine coolant in the transmission fluid is generally caused by a cooler malfunction. The only remedy is to replace
the radiator as the cooler in the radiator is not a serviceable part. If coolant has circulated through the transmission,
an overhaul is necessary.
The torque converter should also be replaced whenever a failure generatessludge and debris. This is necessary
because normal converter flushing procedures will not remove all contaminants.
STANDARD PROCEDURE
FLUID LEVEL CHECK
Low fluid level can cause a variety of conditions because it allows the pumpto take in air along with the fluid. As
in any hydraulic system, air bubbles make the fluid spongy, therefore, pressures will be low and build up slowly.
Improper filling can also raise the fluid level too high. When the transmssion has too much fluid, the geartrain
churns up foam and cause the same conditions which occur with a low fluid level.
In either case, air bubbles can cause overheating and/or fluid oxidation,and varnishing. This can interfere with nor-
mal valve, clutch, and accumulator operation. Foaming can also result in fluid escaping from the transmission vent
where it may be mistaken for a leak.
After the fluid has been checked, seat the dipstick fully to seal out water and dirt.
The transmission has a dipstick to check oil level. It is located on the right side of the engine. Be sure to wipe all
dirt from dipstick handle before removing.
The torque converter fills in both the P(PARK) and N (NEUTRAL) positions. Place the selector lever in P (PARK)
to be sure that the fluid level check is accurate.The engine should be running at idle speed for at least one
minute, with the vehicle on level ground.At normal operating temperature (approximately 82° C. or 180° F), the
fluid level is correct if it is in the HOT region (cross-hatched area) on theoil level indicator. The fluid level will be
approximately at the upper COLD hole of the dipstick at 21° C (70° F) fluid temperature.
NOTE: Engine and Transmission should be at normal operating temperature before performing this proce-
dure.
1. Start engine and apply parking brake.
2. Shift the transmission into DRIVE for approximately 2 seconds.
3. Shift the transmission into REVERSE for approximately 2 seconds.
4. Shift the transmission into PARK.
5. Hook up scan tool andselect transmission.
6. Select sensors.
7. Read the transmission temperature value.
8. Compare the fluid temperature value with the chart.
9. Adjust transmission fluid level shown on the dipstick according to the Transmission Fluid Temperature Chart.
NOTE: After adding any fluid to the transmission, wait a minimum of 2 minutes for the oil to fully drain from
the fill tube into the transmission before rechecking the fluid level.
10. Check transmission for leaks.
FLUID AND FILTER REPLACEMENT
For proper service intervals (Refer to LUBRICATION & MAINTENANCE/MAINTENANCE SCHEDULES - DESCRIP-
TION).
REMOVAL
1. Hoist and support vehicle on safety stands.
2. Place a large diameter shallow drain pan beneath the transmission pan.
3. Remove bolts holding front and sides of pan to transmission.
4. Loosen bolts holding rear of pan to transmission.
5. Slowly separate front of pan away from transmission allowing the fluid to drain into drain pan.
6. Hold up pan and remove remaining bolts holding pan to transmission.
7. While holding pan level, lower pan away from transmission.
8. Pour remaining fluid in pan into drain pan.
9. Remove the screw holding the primary oil filter (1)
to valve body.
10. Separate filter from valve body and oil pump and
pour fluid in filter into drain pan.
11. Inspect the oil filter seal in the bottom of the oil
pump. If the seal is not installed completely in the
oil pump, or is otherwise damaged, then remove
and discard the oil filter seal from the bottom of
the oil pump. If the seal is installed correctly and
is in good condition, it can be reused.
12. If replacing the cooler return filter (2), use Oil Fil-
ter Wrench 8321 to remove the filter from the
transmission.
13. Dispose of used trans fluid and filter(s) properly.
INSPECTION
Inspect bottom of pan and magnet for excessive amounts of metal. A light coating of clutch material on the bottom
of the pan does not indicate a problem unless accompanied by a slipping condition or shift lag. If fluid and pan are
contaminated with excessive amounts of debris, refer to the diagnosis section of this group.
CLEANING
1. Using a suitable solvent, clean pan and magnet.
2. Using a suitable gasket scraper, clean original sealing material from surface of transmission case and the trans-
mission pan.