INSTALLATION
1. Check torque converter hub inner and outer diam-
eters and hub drive notches for sharp edges burrs,
scratches, or nicks. Polish the hub and notches
with 320/400 grit paper and crocus cloth if neces-
sary. The hub must be smooth to avoid damaging
pump seal at installation.
2. Lubricate pocket in the rear oil pump seal lip with
transmission fluid.
3. Lubricate converter pilot hub of the crankshaft with
a light coating of Mopar
High Temp Grease.
4. Align and install converter in 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 19mm (0.75 in.) to rear of straightedge when
converter is fully seated.
7. Temporarily secure converter with C-clamp.
8. For vehicles equipped with a diesel engine;
a. Position transmission on jack and secure it
with chains.
b. Check condition of converter driveplate.
Replace the plate if cracked, distorted or dam-
aged.Also be sure transmission dowel pins
are seated in engine block and protrude far
enough to hold transmission in alignment.
c. Raise transmission and align converter with
drive plate and converter housing with engine
block.
d. Move transmission forward. Then raise, lower
or tilt transmission to align converter housing
with engine block dowels.
e. Carefully work transmission forward and over
engine block dowels until converter hub is
seated in crankshaft.
f. Install bolts (5) attaching transmission (3) to
engine adapter (2).
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.
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).
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.
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
5. Remove o-ring seal (11) from pump body. Discard seal after removal.
6. Remove oil pump seal (1). Discard seal after removal.
CLEANING
Clean pump and support components with solvent and dry them with compressedair.
INSPECTION
Check condition of the seal rings and thrust washer on the reaction shaft support. The seal rings do not need to be
replaced unless cracked, broken, or severely worn.
Inspect the pump and support components. Replace the pump or support if theseal ring grooves or machined sur-
faces are worn, scored, pitted, or damaged. Replace the pump gears if pitted, worn chipped, or damaged.
Inspect the pump bushing. Then check the reaction shaft support bushing. Replace either bushing only if heavily
worn, scored or damaged. It is not necessary to replace the bushings unlessthey are actually damaged.
Oil Pump Assembly
1 - OIL SEAL 7 - BOLTS (6)
2 - VENT BAFFLE 8 - #1 THRUST WASHER (SELECTIVE)
3 - OIL PUMP BODY 9 - INNER GEAR
4 - GASKET 10 - OUTER GEAR
5 - REACTION SHAFT SUPPORT 11 - “O” RING
6 - SEAL RINGS 12 - TORQUE CONVERTER SEAL RING