8. Remove thrust washer (2) from rear planetary
annulus gear (1).
INSPECTION
Inspect the planetary gear sets and annulus gears. The planetary pinions,shafts, washers, and retaining pins are
serviceable. However, if a pinion carrier is damaged, the entire planetarygearsetmustbereplacedasanassembly.
Replace the annulus gears if the teeth are chipped, broken, or worn, or the gear is cracked. Replace the planetary
thrust plates and the tabbed thrust washers if cracked, scored or worn.
Inspect the machined surfaces of the intermediate shaft. Be sure the oil passages are open and clear. Replace the
shaft if scored, pitted, or damaged.
Inspect the sun gear and driving shell. If either component is worn or damaged, remove the sun gear rear retaining
ring and separate the sun gear and thrust plate from the driving shell. Thenreplace the necessary component.
Replace the sun gear as an assembly if the gear teeth are chipped or worn. Also replace the gear as an assembly
if the bushings are scored or worn. The sun gear bushings are not serviceable. Replace the thrust plate if worn, or
severely scored. Replace the driving shell if distorted, cracked, or damaged in any way.
Replace all snap-rings during geartrain assembly. Reusing snap-rings isnot recommended.
ASSEMBLY
1. Lubricate sun gear (2) and planetary gears with
transmission fluid during assembly. Use petroleum
jelly to lubricate intermediate shaft bushing sur-
faces, thrust washers and thrust plates (3) and to
hold these parts in place during assembly.
2. Install front snap-ring on sun gear (2) and install
gear in driving shell. Then install thrust plate (3)
over sun gear and against rear side of driving shell
(1). Install rear snap-ring (4) to secure sun gear
and thrust plate in driving shell. Note that the large
ID chamfer on the sun gear goes forward.
CLUTCH-REAR
DESCRIPTION
The rear clutch assembly is composed of the rear clutch retainer (1), pressure plate (8), clutch plates (12), driving
discs (9), piston (15), Belleville spring (7), and snap-rings (10). The Belleville spring acts as a lever to multiply the
force applied on to it by the apply piston. The increased apply force on the rear clutch pack, in comparison to the
front clutch pack, is needed to hold against the greater torque load imposed onto the rear pack. The rear clutch is
directly behind the front clutch and is considered a driving component.
NOTE: The number of discs and plates may vary with each engine and vehicle combination.
OPERATION
To apply the clutch, pressure is applied between the clutch retainer and piston. The fluid pressure is provided by the
oil pump, transferred through the control valves and passageways, and enters the clutch through the hub of the
reaction shaft support. With pressure applied between the clutch retainer and piston, the piston moves away from
the clutch retainer and compresses the clutch pack. This action applies the clutch pack, allowing torque to flow
through the input shaft into the driving discs, and into the clutch plates and pressure plate that are lugged to the
clutch retainer. The waved spring is used to cushion the application of theclutch pack. The snap-ring is selective
and used to adjust clutch pack clearance.
When pressure is released from the piston, the spring returns the piston toits fully released position and disen-
gages the clutch. The release spring also helps to cushion the applicationof the clutch assembly. When the clutch
is in the process of being released by the release spring, fluid flows through a vent and one-way ball-check-valve
located in the piston. The check-valve is needed to eliminate the possibility of plate drag caused by centrifugal force
acting on the residual fluid trapped in the clutch piston retainer.
Rear Clutch Components
1 - REAR CLUTCH RETAINER 11 - REACTION PLATE
2 - TORLON™ SEAL RINGS 12 - CLUTCH PLATES
3 - INPUT SHAFT 13 - WAVE SPRING
4 - PISTON RETAINER 14 - SPACER RING
5 - OUTPUT SHAFT THRUST WASHER 15 - PISTON
6 - INNER PISTON SEAL 16 - OUTER PISTON SEAL
7 - PISTON SPRING 17 - REAR SEAL RING
8 - PRESSURE PLATE 18 - FIBER THRUST WASHER
9 - CLUTCH DISCS 19 - RETAINING RING
10 - SNAP-RING (SELECTIVE)
CONVERTER-TORQUE
DESCRIPTION
The torque converter is a hydraulic device that cou-
ples the engine crankshaft to the transmission. The
torque converter consists of an outer shell with an
internal turbine (1), a stator (4), an overrunning clutch,
an impeller (2), and an electronically applied converter
clutch (6). The converterclutch provides reduced
engine speed and greater fuel economy when
engaged. Clutch engagement also provides reduced
transmission fluid temperatures. The torque converter
hub drives the transmission oil (fluid) pump.
The torque converter is a sealed, welded unit that is
not repairable and is serviced as an assembly.
CAUTION: The torque converter must be replaced
if a transmission failure resulted in large amounts
of metal or fiber contamination in the fluid.
IMPELLER
The impeller is an integral part of the converter housing. The impeller consists of curved blades placed radially
along the inside of the housing on the transmission side of the converter. As the converter housing is rotated by the
engine, so is the impeller, because they are one and the same and are the driving members of the system.
Impeller
1 - ENGINE FLEXPLATE 4 - ENGINE ROTATION
2 - OIL FLOW FROM IMPELLER SECTION INTO TURBINE
SECTION5 - ENGINE ROTATION
3 - IMPELLER VANES AND COVER ARE INTEGRAL
TURBINE
The turbine is the output, or driven, member of the converter. The turbine is mounted within the housing opposite
the impeller, but is not attached to the housing. The input shaft is inserted through the center of the impeller and
splined into the turbine. The design of the turbine is similar to the impeller, except the blades of the turbine are
curved in the opposite direction.
STATOR
The stator assembly is mounted on a stationary shaft
which is an integral part of the oil pump. The stator
contains an over-running clutch (1-4), which allows the
stator to rotate only in a clockwise direction. When the
stator is locked against theover-runningclutch,the
torque multiplication feature of the torque converter is
operational.
Turbine
1 - TURBINE VANE 4 - PORTION OF TORQUE CONVERTER COVER
2 - ENGINE ROTATION 5 - ENGINE ROTATION
3 - INPUT SHAFT 6 - OIL FLOW WITHIN TURBINE SECTION
STATOR
Torque multiplication is achieved by locking the sta-
tor’s over-running clutch to its shaft. Under stall condi-
tions the turbine is stationary and the oil leaving the
turbine blades strikes the face of the stator blades and
tries to rotate them in a counterclockwise direction.
When this happens the overrunning clutch of the sta-
tor locks and holds the stator from rotating. With the
stator locked, the oil strikes the stator blades (1) and
is redirected into a “helping” direction before it enters
the impeller. This circulation of oil from impeller to tur-
bine, turbine to stator, and stator to impeller, can pro-
duce a maximum torque multiplication of about 1.75:1.
As the turbine begins to match the speed of the impel-
ler, the fluid that was hitting the stator in such as way
as to cause it to lock-up is no longer doing so. In this
condition of operation, the stator begins to free wheel
and the converter acts as a fluid coupling.
TORQUE CONVERTER CLUTCH (TCC)
The torque converter clutch is hydraulically applied or released when fluid is feed or vented from the hydraulic circuit
by the torque converter control (TCC) solenoid on the valve body. The torque converter clutch is controlled by the
Powertrain Control Module (PCM). The torque converter clutch engages in FOURTH gear, and in THIRD gear under
various conditions, such as when the O/D switch is OFF, or when the vehicle is cruising on a level surface after the
vehicle has warmed up. The torque converter clutch can also be engaged in the MANUAL SECOND gear position
if high transmission temperatures are sensed by the PCM. The torque converter clutch may disengage momentarily
when an increase in engine load is sensed by the PCM, such as when the vehiclebegins to go uphill or the throttle
pressure is increased.
REMOVAL
1. Remove transmission and torque converter from vehicle. (Refer to 21 - TRANSMISSION/AUTOMATIC - 45RFE/
545RFE - REMOVAL)
2. Place a suitable drain pan under the converter housing end of the transmission.
CAUTION: Verify that transmission is secure on the lifting device or work surface, the center of gravity of
the transmission will shift when the torque converter is removed creatingan unstable condition. The torque
converter is a heavy unit. Use caution when separating the torque converter from the transmission.
3. Pull the torque converter forward until the center hub clears the oil pumpseal.
4. Separate the torque converter from the transmission.
Stator Operation
1 - DIRECTION STATOR WILL FREE WHEEL DUE TO OIL
PUSHING ON BACKSIDE OF VANES
2-FRONTOFENGINE
3 - INCREASED ANGLE AS OIL STRIKES VANES
4 - DIRECTION STATOR IS LOCKED UP DUE TO OIL PUSHING
AGAINST STATOR VANES
INSTALLATION
Check converter hub and drive notches for sharp
edges, burrs, scratches, or nicks. Polish the hub and
notches with 320/400 grit paper or crocus cloth if nec-
essary. The hub must be smooth to avoid damaging
the pump seal at installation.
1. Lubricate oil pump seal lip with transmission fluid.
2. Place torque converter in position on transmission.
CAUTION: Do not damage oil pump seal or bush-
ing while inserting torqueconverterintothefront
of the transmission.
3. Align torque converter to oil pump seal opening.
4. Insert torque converter hub into oil pump.
5. While pushing torque converter inward, rotate con-
verter until converter is fully seated in the oil pump
gears.
6. Check converter seating with a scale (1) and
straightedge (2). Surface of converter lugs should
be 19mm (0.75 in.) to the rear of the straightedge when converter is fully seated.
7. If necessary, temporarily secure converter with C-clamp attached to the converter housing.
8. Install the transmission in the vehicle.
9. Fill the transmission with the recommended fluid.
VALVE-TORQUE CONVERTER DRAINBACK
DESCRIPTION
GAS ENGINES
The drainback valve is located in the transmission cooler outlet (pressure) line.
DIESEL ENGINE
The converter drainback check valve is located in the in the TOC pressure - supply line, between the engine
mounted TOC and the air to oil TOC.
OPERATION
GAS ENGINES
The valve prevents fluid from draining from the converter into the cooler and lines when the vehicle is shut down for
lengthy periods. Production valves have a hose nipple at one end, while theopposite end is threaded for a flare
fitting. All valves have an arrow (or similar mark) to indicate direction of flow through the valve.
DIESEL ENGINE
The valve prevents fluid from draining from the converter into the cooler and lines when the vehicle is shut down for
lengthy periods. Production valves have pipe thread on one end, while the opposite end is threaded for a flare
fitting, and are threaded into the oil cooler mounted on the side of the engine. All valves have an arrow (or similar
mark) to indicate direction of flow through the valve.
STANDARD PROCEDURE
GAS ENGINES
The converter drainback check valve is located in the cooler outlet (pressure) line near the radiator tank. The valve
prevents fluid drainback when the vehicle is parked for lengthy periods. The valve check ball is spring loaded and
has an opening pressure of approximately 2 psi.
The valve is serviced as an assembly; it is not repairable. Do not clean the valve if restricted, or contaminated by
sludge, or debris. If the valve fails, or if a transmission malfunction occurs that generates significant amounts of
sludge and/or clutch particles and metal shavings, the valve must be replaced.
If the valve is restricted, installed backwards, or in the wrong line, it will cause an transmission overheating condition
and possible transmission failure.
CAUTION: The drainback valve is a one-way flow device. It must be properly orientedintermsofflowdirec-
tion for the cooler to function properly. The valve must be installed in thepressure line. Otherwise flow will
be blocked and would cause an transmission overheating condition and eventual transmission failure.
DIESEL ENGINE
The converter drainback check valve is located in the in the TOC pressure - supply line, between the engine
mounted transmission oil cooler and the air to oil transmission oil cooler. The valve prevents fluid drainback when
the vehicle is parked for lengthy periods. The valve check ball is spring loaded and has an opening pressure of
approximately 2 psi.
The valve is serviced as an assembly; it is not repairable. Do not clean the valve if restricted, or contaminated by
sludge, or debris. If the valve fails, or if a transmission malfunction occurs that generates significant amounts of
sludge and/or clutch particles and metal shavings, the valve must be replaced.
If the valve is restricted, installed backwards, or in the wrong line, it will cause an transmission overheating condition
and possible transmission failure.