OPERATION
Both the accumulator and the 3-4 accumulator func-
tion the same. Line pressure (1) is directed to the
small end of the piston when the transmission is
placed into a DRIVE position, bottoming it against the
accumulator plate.
Diesel version shown.
When the 1-2 upshift occurs, line pressure (2) is
directed to the large end of the piston and then to the
kickdown servo. As the line pressure reaches the
accumulator, the combination of spring pressure and
line pressure forces the piston away from the accumu-
lator plate. This causes a balanced pressure situation,
which results in a cushioned band application. After
the kickdown servo has become immovable, line pres-
sure will finish pushing the accumulator up into its
bore (1). When the large end of the accumulator pis-
ton is seated in its bore, the band or clutch is fully
applied.
NOTE: The accumulator is shown in the inverted
position for illustrative purposes.
INSPECTION
Inspect the accumulator piston and seal rings. Replace the seal rings if worn or cut. Replace the piston if chipped
or cracked.
Check condition of the accumulator inner and outer springs. Replace the springs if the coils are cracked, distorted
or collapsed.
ADJUSTMENTS
ADJUSTMENT - BANDS
FRONT BAND
The front (kickdown) band adjusting screw (2) is
located on the left side of the transmission case above
the manual valve and throttle valve levers.
1. Raise vehicle.
2. Loosen band adjusting screw locknut. Then back
locknut (1) off 3-5 turns. Be sure adjusting screw
turns freely in case. Apply lubricant to screw
threads if necessary.
3. Tighten band adjusting screw to 8 Nꞏm (72 in. lbs.)
torque with an appropriate Torx™ socket.
CAUTION: If Adapter C-3705 is needed to reach
the adjusting screw, tighten the screw to only 5
Nꞏm (47-50 in. lbs.) torque.
4. Back off front band adjusting screw 1-3/4 turns, for
diesel vehicles, or 1-1/2 turns, for V-10 vehicles.
5. Hold adjuster screw in position and tighten locknut to 41 Nꞏm (30 ft. lbs.) torque.
6. Lower vehicle.
REAR BAND
The transmission oil pan must be removed for access
to the rear band adjusting screw (1).
1. Raise vehicle.
2. Remove transmission oil pan and drain fluid.
3. Loosen band adjusting screw locknut 5-6 turns. Be
sure adjusting screw turns freely in lever.
4. Tighten adjusting screw to 8 Nꞏm (72 in. lbs.)
torque.
5. Back off adjusting screw 3 turns.
6. Hold adjusting screw in place and tighten locknut to
34 Nꞏm (25 ft. lbs.) torque.
7. Position new gasket on oil pan and install pan on
transmission. Tighten pan bolts to 17 Nꞏm (13 ft.
lbs.) torque.
8. Lower vehicle and refill transmission with Mopar
ATF +4, Automatic Transmission fluid.
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.
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.
Fluid level is checked with the engine running at curb idle speed, the transmissioninNEUTRALandthetransmis-
sion fluid at normal operating temperature.The engine should be running at idle speed for at least one minute,
with the vehicle on level ground.
The transmission fluid level can be checked two ways.
PROCEDURE ONE
1. Transmission fluid must be at normal operating
temperature for accurate fluid level check. Drive
vehicle if necessary to bring fluid temperature up to
normal hot operating temperature of 82°C (180°F).
2. Position vehicle on level surface.
3. Start and run engine at curb idle speed.
4. Apply parking brakes.
5. Shift transmission momentarily into all gear ranges.
Then shift transmission back to NEUTRAL.
6. Clean top of filler tube and dipstick to keep dirt from entering tube.
7. Remove dipstick (1) and check fluid level as follows:
a. Correct acceptable level is in crosshatch area.
b. Correct maximum level is to MAX arrow mark.
c. Incorrect level is at or below MIN line.
d. If fluid is low, add only enough Mopar
ATF +4 to restore correct level. Do not overfill.
PROCEDURE TWO
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 DRB
scan tool and select engine.
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 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). The service fluid fill after a filter change is approximately 3.8 liters (4.0 quarts).
REMOVAL
1. Hoist and support vehicle on safety stands.
2. Place a large diameter shallow drain pan beneath
the transmission pan (3).
3. Remove bolts holding front and sides of pan to
transmission (1).
4. Loosen bolts holding rear of pan to transmission.
5. Slowly separate front of pan and reusable gasket
(2) away from transmission allowing the fluid to
drain into drain pan.
6. Hold up pan and remove remaining bolt holding
pan to transmission.
7. While holding pan level, lower pan and gasket
away from transmission.
8. Pour remaining fluid in pan into drain pan.
9. Remove screws holding filter (2) to valve body.
10. Separate filter from valve body and pour fluid in
filter into drain pan.
11. Dispose of used trans fluid and filter properly.
INSTALLATION
1. Position a new transmission oil filter (2) onto the
valve body.
2. Install the screws to hold the filter to the valve
body. Tighten the screws to 4 Nꞏm (35 in.lbs.).
3. Clean the gasket surfaces of the transmission oil
pan (3) and transmission pan rail.
NOTE: The transmission pan oil gasket (2) is reus-
able. Inspect the sealing surfaces of the gasket. If
the sealing ribs on both surfaces appear to be in
good condition, clean the gasket of any foreign
material and reinstall.
4. Position the oil pan gasket (2) onto the oil pan (3).
5. Position the oil pan and gasket onto the transmis-
sion and install several bolts to hold the pan and
gasket to the transmission.
6. Install the remainder of the oil pan bolts. Tighten
the bolts to 13.6 Nꞏm (125 in.lbs.).
7. Lower vehicle and fill transmission. (Refer to 21 -
TRANSMISSION/AUTOMATIC/FLUID - STANDARD PROCEDURE)
TRANSMISSION FILL
To avoid overfilling transmission after a fluid change or overhaul, perform the following procedure:
1. Remove dipstick and insert clean funnel in transmission fill tube.
2. Add following initial quantity of Mopar
ATF+4totransmission:
a. If only fluid and filter were changed, add3 pints (1-1/2 quarts)of ATF +4 to transmission.
b. If transmission was completely overhauled, torque converter was replaced or drained, and cooler was
flushed, add12 pints (6 quarts)of ATF +4 to transmission.
3. Apply parking brakes.
4. Start and run engine at normal curb idle speed.
5. Apply service brakes, shift transmission through all gear ranges then back to NEUTRAL, set parking brake, and
leave engine running at curb idle speed.
6. Remove funnel, insert dipstick andcheck fluid level. If level is low,add fluid to bring level to MIN mark on
dipstick.Check to see if the oil level is equal on both sides of the dipstick. If one side is noticably higher than
the other, the dipstick has picked up some oil from the dipstick tube. Allowthe oil to drain down the dipstick tube
and re-check.
7. Drive vehicle until transmission fluid is at normal operating temperature.
8. With the engine running at curb idle speed, the gear selector in NEUTRAL,and the parking brake applied, check
the transmission fluid level.
CAUTION: Do not overfill transmission, fluid foaming and shifting problems can result.
9. Add fluid to bring level up to MAX arrow mark.
When fluid level is correct, shut engine off, release park brake, remove funnel, and install dipstick in fill tube.