valve train DODGE RAM SRT-10 2006 Service Repair Manual

GOVERNOR-ELECTRONIC
DESCRIPTION
Governor pressure is controlled electronically. Components used for governor pressure control include:
Governor body
Valve body transfer plate
Governor pressuresolenoid valve
Governor pressure sensor
Fluid temperature thermistor
Throttle position sensor (TPS)
Transmission speed sensor
Powertrain control module (PCM)
GOVERNOR PRESSURE SOLENOID VALVE
The solenoid valve (2) is a duty-cycle solenoid which
regulates the governor pressure needed for upshifts
and downshifts. It is an electro-hydraulic device
located in the governor body on the valve body trans-
fer plate.
GOVERNOR BODY, TRANSFER PLATE, AND PRESSURE SENSOR
The governor pressure sensor (2) measures output
pressure of the governor pressure solenoid valve.
The transfer plate is designed to supply transmission
line pressure to the governor pressure solenoid valve
and to return governor pressure.
The governor pressure solenoid valve is mounted in
the governor body (1). The body is bolted to the lower
side of the transfer plate.
GOVERNOR PRESSURE CURVES
There are four governor pressure curves programmed into the transmissioncontrol module. The different curves
allow the control module to adjust governor pressure for varying conditions. One curve is used for operation when
fluid temperature is at, or below, –1°C (30°F). A second curve is used when fluid temperature is at, or above, 10°C
(50°F) during normal city or highway driving. A third curve is used during wide-open throttle operation. The fourth
curve is used when driving with the transfer case in low range.

OPERATION
Compensation is required for performance variations of two of the input devices. Though the slope of the transfer
functions is tightly controlled, offset may vary due to various environmental factors or manufacturing tolerances.
The pressure transducer is affected by barometric pressure as well as temperature. Calibration of the zero pressure
offset is required to compensate for shifting output due to these factors.
Normal calibration will be performed when sump temperature is above 50 degrees F, or in the absence of sump
temperature data, after the first 10 minutes of vehicle operation. Calibration of the pressure transducer offset occurs
each time the output shaft speed falls below 200 RPM. Calibration shall be repeated each 3 seconds the output
shaft speed is below 200 RPM. A 0.5 second pulse of 95% duty cycle is applied to the governor pressure solenoid
valve and the transducer output is read during this pulse. Averaging of thetransducer signal isnecessary to reject
electrical noise.
Under cold conditions (below 50 degrees F sump), the governor pressure solenoid valve response may be too slow
to guarantee 0 psi during the 0.5 second calibration pulse. Calibration pulses are continued during this period, how-
ever the transducer output valves are discarded. Transducer offset must be read at key-on, under conditions which
promote a stable reading. This value is retained and becomes the offset during the
coldperiod of operation.
GOVERNOR PRESSURE SOLENOID VALVE
The inlet side of the solenoid valve is exposed to normal transmission linepressure. The outlet side of the valve
leads to the valve body governor circuit.
The solenoid valve regulates line pressure to produce governor pressure.Theaveragecurrentsuppliedtothesole-
noid controls governor pressure. One amp current produces zero kPa/psi governor pressure. Zero amps sets the
maximum governor pressure.
The powertrain control module (PCM) turns on the trans control relay whichsupplies electrical power to the solenoid
valve. Operating voltage is 12 volts (DC). The PCM controls the ground sideof the solenoid using the governor
pressure solenoidcontrol circuit.
GOVERNOR PRESSURE SENSOR
The sensor output signal provides the necessary feedback to the PCM. This feedback is needed to adequately
control governor pressure.
GOVERNOR BODY AND TRANSFER PLATE
The transfer plate channels line pressure to the solenoid valve through the governor body. It also channels governor
pressure from the solenoid valve to the governor circuit. It is the solenoid valve that develops the necessary gov-
ernor pressure.
GOVERNOR PRESSURE CURVES
LOW TRANSMISSION FLUID TEMPERATURE
When the transmission fluid is cold the conventional governor can delay shifts, resulting in higher than normal shift
speeds and harsh shifts. The electronically controlled low temperature governor pressure curve is higher than nor-
mal to make the transmission shift at normal speeds and sooner. The PCM usesa temperature sensor in the trans-
mission oil sump to determine when low temperature governor pressure is needed.
NORMAL OPERATION
Normal operation is refined through the increased computing power of the PCM and through access to data on
engine operating conditions provided by the PCM that were not available with the previous stand-alone electronic
module. This facilitated the development of a load adaptive shift strategy - the ability to alter the shift schedule in
response to vehicle load condition. One manifestation of this capabilityis grade
huntingprevention - the ability of
the transmission logic to delay an upshift on a grade if the engine does not have sufficient power to maintain speed
in the higher gear. The 3-2 downshift and the potential for hunting betweengears occurs with a heavily loaded
vehicle or on steep grades. When hunting occurs, it is very objectionable because shifts are frequent and accom-
panied by large changes in noise and acceleration.

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 two primary causes.
1. 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.
2. 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.

CLUTCH-FRONT
DESCRIPTION
The front clutch assembly is composed of the front clutch retainer (11), pressure plate, clutch plates (4), clutch discs
(7), clutch piston (2), clutch piston return spring (9), clutch piston spring retainer (3), and snap-rings (5, 8). The front
clutch is the forward-most component in the transmission geartrain and isdirectly behind the oil pump and is con-
sidered a driving component.
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 snap-ring is used to cushion the application ofthe clutch pack.
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 clutch retainer. The check-valve is needed to eliminate thepossibility of plate drag caused by cen-
trifugal force acting on the residual fluid trapped in the clutch piston retainer.
48RE Front Clutch Components
1 - INNER PISTON SEAL 7 - CLUTCH DISCS
2 - CLUTCH PISTON 8 - RETAINER SNAP-RING
3 - CLUTCH PISTON SPRING RETAINER 9 - CLUTCH PISTON SPRINGS
4 - CLUTCH PLATES 10 - OUTER PISTON SEAL
5 - CLUTCH PACK SNAP-RING (WAVED) 11 - FRONT CLUTCH RETAINER
6 - REACTION PLATE

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

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 pressure regulator valve is located in the valve body near the manual valve. The
pressure regulator valve train controls the maximum pressure in the linesby metering the dumping of fluid back into
the sump. Regulated pressure is referred to as “line pressure.”
The regulator valve 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 closing of the dump will cause the oil pressure to increase. Oil pressure on the oppo-
site 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 pressureto maintain the oil at specific pressures. With the engine running, fluid flows
from the pump to the pressure regulator valve, manual valve, and the interconnected circuits. As fluid is sent
through passages to the regulator 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
selector in the PARK position, fluid recirculates through the regulator and manual valves back to the sump.
Regulator Valve in Park Position

The regulated line pressure in REVERSEis held at much higher pressures than in the other gear positions: 145-280
psi. The higher pressure for REVERSE isachieved by the manual valve blocking the supply of line pressure to the
reaction area left of land #4. With this pressure blocked, there is less area for pressure to act on to balance the
force of the spring on the right. This allows line pressure to push the valvetrain to the right, reducing the amount
of fluid returned to the pump’s inlet, increasing line pressure.
KICKDOWN VALVE
When the throttle valve is as far over to the left as it can go, the maximum line pressure possible will enter the
throttle pressure circuit. In this case, throttle pressure will equal line pressure. With the kickdown valve pushed into
the bore as far as it will go, fluid initially flows through the annular groove of the 2-3 shift valve (which will be in the
direct drive position to the right).
After passing the annular groove, the fluid is routed to the spring end of the 2-3 shift valve. Fluid pressure reacting
on the area of land #1 overcomes governor pressure, downshifting the 2-3 shift valve into the kickdown, or second
gear stage of operation. The valve is held in the kickdown position by throttle pressure routed from a seated check
ball (#2). Again, if vehicle speed is low enough, throttle pressure will also push the 1-2 shift valve left to seat its
governor plug, and downshift to drive breakaway.
Kickdown Valve - Wide Open Throttle

and volume must be regulated to maintain the balance within the transmission. To do this, throttle pressure is routed
tothereactionareaontherightsideofthethrottlepressureplug(intheregulator valve).
The higher engine speed and line pressure would open the vent too far and reduce line pressure too much. Throttle
pressure, which increases with engine speed (throttle opening), is used to oppose the movement of the pressure
valve to help control the metering passage at the vent. The throttle pressure is combined with spring pressure to
reduce the force of the throttle pressure plug on the pressure valve. The larger spring at the right closes the reg-
ulator valve passage and maintains or increases line pressure. The increased line pressure works against the reac-
tion area of the line pressure plug and the reaction area left of land #3 simultaneously moves the regulator valve
train to the right and controls the metering passage.
The kickdown valve, along with the throttle valve, serve to delay upshiftsuntil the correct vehicle speed has been
reached. It also controls downshifts upon driver demand, or increased engine load. If these valves were not in
place, the shift points would be at the same speed for all throttle positions. The kickdown valve is actuated by a
cam connected to the throttle. This is accomplished through either a linkage or a cable. The cam forces the kick-
down valve toward the throttle valve compressing the spring between them and moving the throttle valve. As the
throttle valve land starts to uncover its port, line pressure is “metered”out into the circuits and viewed as throttle
pressure. This increased throttle pressure is metered out into the circuits it is applied to: the 1-2 and 2-3 shift
valves. When the throttle pressure is high enough, a 3-2 downshift will occur. If the vehicle speed is low enough, a
2-1 downshift will occur.

NOTE: When connecting the service equipment coupling to the line fitting,verify that the valve of the cou-
pling is fully closed. This will reduce the amount of effort required to make the connection.
NOTE: The work area ambient temperature must be above 21° C (70° F) and the evaporator temperature
must be above 13° C (55° F) prior to conducting the A/C Performance Test.
1. Conduct the A/C System Performance Test (Cooldown Test) found within the HVAC System Test (refer to 24 -
HVAC Electrical Diagnostics). If no diagnostic trouble codes (DTCs) are found in the A/C-heater control, power-
train control module (PCM) or engine control module (ECM) (depending on engine application), gateway module
or the totally integrated power module (TIPM), go to Step 2. If any DTCs are found, repair as required, then
proceedtoStep2.
2. Connect a tachometer and a manifold gauge set or an A/C recycling/charging station.
3. Operate the heating-A/C system under the following conditions.
Engine at 1,000 rpm at operating temperature
Door or windows open
Transmission in Park or Neutral with parking brake set (depending on application)
A/C-heater controls set to Recirculation mode (max-A/C), full cool, panel mode, high blower and with A/C com-
pressor engaged. If the A/C compressor does not engage, see the A/C System Diagnosis chart.
4. Insert a thermometer in the driver side center panel air outlet and operate the A/C system until the thermometer
temperature stabilizes.
5. With the A/C compressor clutch engaged, compare the air temperature at the center panel outlet and the A/C
compressor discharge pressure (high side) to the A/C Performance Temperature and Pressure chart. The com-
pressor clutch may cycle, depending upon the ambient temperature and humidity. If the clutch cycles, use the
readings obtained before the clutch disengaged.
A/C PERFORMANCE TEMPERATURE AND PRESSURE
Ambient Air
Temperature21° C
(70° F)27° C
(80° F)32° C
(90° F)38° C
(100° F)43° C
(110° F)
Air Temperature at
Center Panel Outlet7° C
(45° F)7° C
(45° F)13° C
(55° F)13° C
(55° F)18° C
(64° F)
Compressor Inlet
Pressure at Service
Port (low Side)138 to 207 kPa
(20to30psi)172to241kPa
(25to35psi)207 to 276
kPa
(30to40psi)241 to 310
kPa
(35to45psi)276to345kPa
(40to50psi)
Compressor
Discharge Pressure at
Service Port (High
Side)1034 to 1724
kPa
(150 to 250
psi)1379to2068
kPa
(200 to 300
psi)1724to2413
kPa
(250 to 350
psi)1999 to 2689
kPa
(290 to 390
psi)2413to2965
kPa
(350 to 430 psi)
6. If the air outlet temperature fails to meet the specifications in the A/CPerformance Temperature and Pressure
chart, or if the A/C compressor discharge pressure is high, refer to the A/CSystem Diagnosis chart.
A/C SYSTEM DIAGNOSIS
Condition Possible Causes Correction
Constant compressor
engagement and warm air
from passenger vents.1. Low refrigerant system
charge.1. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.
Equal pressures, but the
compressor clutch does not
engage.1. No refrigerant in the
refrigerant system.1. See Refrigerant System Leaks in this group.
Test the refrigerant system for leaks. Repair,
evacuate and charge the refrigerant system, if
required.

TRANSDUCER-A/C PRESSURE
DESCRIPTION
The A/C pressure transducer (1) is a switch that is
installed on a fitting located on the A/C discharge line.
An internally threaded fitting on the A/C pressure
transducer connects it to the externally threaded
Schrader-type fitting on the A/C discharge line. A rub-
ber O-ring seals the connection between the A/C pres-
sure transducer and the discharge line fitting. The A/C
pressure transducer is connected to the vehicle elec-
trical system by a molded plastic connector with three
terminals.
OPERATION
The A/C pressure transducer monitors the pressures in the high side of the refrigerant system through its connection
to a fitting on the A/C discharge line. The A/C pressure transducer will change its internal resistance in response to
the pressures it monitors. A Schrader-type valve in the A/C discharge linefitting permits the A/C pressure transducer
to be removed or installed without disturbing the refrigerant in the A/C system.
The A/C pressure transducer will change its internal resistance in response to the pressures it monitors. The pow-
ertrain control module (PCM) or the engine control module (ECM) (depending on engine application) provides a five
volt reference signal and a sensor ground to the A/C pressure transducer, then monitors the output voltage of the
transducer on a sensor return circuit to determine refrigerant pressure.The PCM/ECM is programmed to respond to
this and other sensor inputs by controlling the operation of the A/C compressor clutch and the radiator cooling fan
to help optimize A/C system performance and to protect the system components from damage. The PCM will dis-
engagetheA/Ccompressorclutchwhenhighsidepressurerisesabove3172kPa (460 psi) and re-engage the
clutch when high side pressure drops below 1999 kPa (290 psi). The A/C pressure transducer will also disengage
the A/C compressor clutch if the high side pressure drops below 193 kPa (28 psi) and will re-engage the clutch
when the high side pressure rises above 234 kPa (34 psi). If the refrigerantpressure rises above 1655 kPa (240
psi), the PCM will actuate the cooling fan. The A/C pressure transducer signal to the PCM/ECM will also prevent the
A/C compressor clutch from engaging when ambient temperatures are below about 10° C (50° F) due to the pres-
sure/temperature relationship of the refrigerant. The A/C pressure transducer input to the PCM/ECM will also pre-
vent the A/C compressor clutch from engaging when ambient temperatures are below about 10° C (50° F) due to
the pressure/temperature relationship of the refrigerant.
The A/C pressure transducer is diagnosed using a scan tool. Refer to 9 - Engine Electrical Diagnostics for more
information.
The A/C pressure transducer cannot be adjusted or repaired and, if faulty or damaged, it must be replaced.
REMOVAL
NOTE: It is not necessary to discharge the refrigerant system to replace the A/C pressure transducer.