2003 JEEP GRAND CHEROKEE pump - standard procedure

STANDARD PROCEDURE - TORQUE
CONVERTER DRAINBACK VALVE........134
TRANSMISSION TEMPERATURE SENSOR
DESCRIPTION........................134
OPERATION..........................134
VALVE BODY
DESCRIPTION........................135
OPERATION..........................139REMOVAL............................154
DISASSEMBLY........................155
CLEANING...........................165
INSPECTION.........................166
ASSEMBLY...........................167
INSTALLATION........................175
ADJUSTMENTS - VALVE BODY...........175
AUTOMATIC TRANSMISSION -
42RE
DESCRIPTION
The 42RE is a four speed fully automatic transmis-
sion (Fig. 1) with an electronic governor. The 42RE is
equipped with a lock-up clutch in the torque con-
verter. First through third gear ranges are provided
by the clutches, bands, overrunning clutch, and plan-
etary gear sets in the transmission. Fourth gear
range is provided by the overdrive unit that contains
an overdrive clutch, direct clutch, planetary gear set,
and overrunning clutch.The transmission contains a front, rear, and direct
clutch which function as the input driving compo-
nents. It also contains the kickdown (front) and the
low/reverse (rear) bands which, along with the over-
running clutch and overdrive clutch, serve as the
holding components. The driving and holding compo-
nents combine to select the necessary planetary gear
components, in the front, rear, or overdrive planetary
gear set, transfer the engine power from the input
shaft through to the output shaft.
The valve body is mounted to the lower side of the
transmission and contains the valves to control pres-
sure regulation, fluid flow control, and clutch/band
application. The oil pump is mounted at the front of
the transmission and is driven by the torque con-
verter hub. The pump supplies the oil pressure nec-
essary for clutch/band actuation and transmission
lubrication.
WJAUTOMATIC TRANSMISSION - 42RE 21 - 3

CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS. 1. Fluid Lines and Fittings
Loose/Leaks/Damaged.1. Tighten fittings. If leaks persist, replace fittings
and lines if necessary.
2. Fill Tube (where tube enters
case) Leaks/Damaged.2. Replace tube seal. Inspect tube for cracks in fill
tube.
3. Pressure Port Plug Loose
Loose/Damaged.3. Tighten to correct torque. Replace plug or
reseal if leak persists.
4. Pan Gasket Leaks. 4. Tighten pan screws (150 in. lbs.). If leaks
persist, replace gasket.
5. Valve Body Manual Lever Shaft
Seal Leaks/Worn.5. Replace shaft seal.
6. Rear Bearing Access Plate
Leaks.6. Replace gasket. Tighten screws.
7. Gasket Damaged or Bolts are
Loose.7. Replace bolts or gasket or tighten both.
8. Adapter/Extension Gasket
Damaged Leaks/Damaged.8. Replace gasket.
9. Park/Neutral Switch, or
Transmission Range Sensor
Leaks/Damaged.9. Replace switch and gasket.
10. Converter Housing Area Leaks. 10. Check for leaks at seal caused by worn seal
or burr on converter hub (cutting seal), worn
bushing, missing oil return, oil in front pump
housing or hole plugged. Check for leaks past
O-ring seal on pump or past pump-to-case bolts;
pump housing porous, oil coming out vent due to
overfill or leak past front band shaft access plug.
11. Pump Seal Leaks/Worn/
Damaged.11. Replace seal.
12. Torque Converter Weld
Leak/Cracked Hub.12. Replace converter.
13. Case Porosity Leaks. 13. Replace case.
NOISY OPERATION
IN FOURTH GEAR
ONLY1. Overdrive Clutch Discs, Plates
or Snap Rings Damaged.1. Remove unit and rebuild clutch pack.
2. Overdrive Piston or Planetary
Thrust Bearing Damaged.2. Remove and disassemble unit. Replace either
thrust bearing if damaged.
3. Output Shaft Bearings
Scored/Damaged.3. Remove and disassemble unit. Replace either
bearing if damaged.
4. Planetary Gears Worn/Chipped. 4. Remove and overhaul overdrive unit.
5. Overdrive Unit Overrunning
Clutch Rollers Worn/Scored.5. Remove and overhaul overdrive unit.
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR
Damaged or worn threads in the aluminum trans-
mission case and valve body can be repaired by the
use of Heli-CoilsŸ, or equivalent. This repair con-
sists of drilling out the worn-out damaged threads.
Then tap the hole with a special Heli-CoilŸ tap, or
equivalent, and installing a Heli-CoilŸ insert, orequivalent, into the hole. This brings the hole back to
its original thread size.
Heli-CoilŸ, or equivalent, tools and inserts are
readily available from most automotive parts suppli-
ers.
21 - 26 AUTOMATIC TRANSMISSION - 42REWJ
AUTOMATIC TRANSMISSION - 42RE (Continued)

(1) A result of restricted fluid flow through the
main and/or auxiliary cooler. This condition is usu-
ally the result of a faulty or improperly installed
drainback valve, a damaged main cooler, or severe
restrictions in the coolers and lines caused by debris
or kinked lines.
(2) Heavy duty operation with a vehicle not prop-
erly equipped for this type of operation. Trailer tow-
ing 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 sys-
tem, and the engine/axle ratio combination needed to
handle heavy loads.
DIAGNOSIS AND TESTING - FLUID
CONTAMINATION
Transmission fluid contamination is generally a
result of:
²adding incorrect fluid
²failure to clean dipstick and fill tube when
checking level
²engine coolant entering the fluid
²internal failure that generates debris
²overheat that generates sludge (fluid break-
down)
²failure to reverse flush cooler and lines after
repair
²failure to replace contaminated converter after
repair
The use of non-recommended fluids can result in
transmission failure. The usual results are erratic
shifts, slippage, abnormal wear and eventual failure
due to fluid breakdown and sludge formation. Avoid
this condition by using recommended fluids only.
The dipstick cap and fill tube should be wiped
clean before checking fluid level. Dirt, grease and
other foreign material 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 withdraw-
ing the dipstick.
Engine coolant in the transmission fluid is gener-
ally 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 transmission cooler and lines should be
reverse flushed whenever a malfunction generates
sludge and/or debris. The torque converter should
also be replaced at the same time.
Failure to flush the cooler and lines will result in
recontamination. Flushing applies to auxiliary coolers
as well. The torque converter should also be replaced
whenever a failure generates sludge and debris. This
is necessary because normal converter flushing proce-
dures will not remove all contaminants.
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK
Low fluid level can cause a variety of conditions
because it allows the pump to 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 condi-
tions 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 normal valve, clutch, and accumulator
operation. Foaming can also result in fluid escaping
from the transmission vent where it may be mis-
taken 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 transmission in NEUTRAL and
the transmission fluid at normal operating tempera-
ture.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 operat-
ing temperature for accurate fluid level check. Drive
vehicle if necessary to bring fluid temperature up to
normal hot operating temperature of 82ÉC (180ÉF).
(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 (Fig. 87) 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 MopartAT F
+4, type 9602, to restore correct level. Do not over-
fill.
21 - 70 AUTOMATIC TRANSMISSION - 42REWJ
FLUID AND FILTER (Continued)

STANDARD PROCEDURE - OIL PUMP VOLUME
CHECK
Measuring the oil pump output volume will deter-
mine if sufficient oil flow to the transmission oil
cooler exists, and whether or not an internal trans-
mission failure is present.
Verify that the transmission fluid is at the proper
level. Refer to the Fluid Level Check procedure in
this section. If necessary, fill the transmission to the
proper level with MopartATF +4, type 9602, Auto-
matic Transmission Fluid.
(1) Disconnect theTo coolerline at the cooler
inlet and place a collecting container under the dis-
connected line.
CAUTION: With the fluid set at the proper level,
fluid collection should not exceed (1) quart or inter-
nal damage to the transmission may occur.
(2) Run the engineat curb idle speed, with the
shift selector in neutral.(3) If one quart of transmission fluid is collected in
the container in 20 seconds or less, oil pump flow vol-
ume is within acceptable limits. If fluid flow is inter-
mittent, or it takes more than 20 seconds to collect
one quart of fluid, refer to the Hydraulic Pressure
tests in this section for further diagnosis.
(4) Re-connect theTo coolerline to the transmis-
sion cooler inlet.
(5) Refill the transmission to proper level.
DISASSEMBLY
(1) Remove seal ring from housing and reaction
shaft support (Fig. 110).
(2) Mark pump housing and support assembly for
alignment reference.
(3) Remove bolts attaching pump body to support
(Fig. 111).
(4) Separate support from pump housing (Fig.
112).
(5) Remove inner and outer gears from reaction
shaft support (Fig. 113).
Fig. 108 Oil Pump and Reaction Shaft Support
1 - REACTION SHAFT SUPPORT
2 - PUMP
Fig. 109 Pump Gear Removal
1 - REACTION SHAFT SUPPORT
2 - INNER GEAR
3 - OUTER GEAR
Fig. 110 Removing Pump Seal Ring
1 - PUMP HOUSING SEAL RING
Fig. 111 Pump Support Bolts
1 - REACTION SHAFT SUPPORT
2 - PUMP
WJAUTOMATIC TRANSMISSION - 42RE 21 - 81
OIL PUMP (Continued)

AUTOMATIC TRANSMISSION - 545RFE
TABLE OF CONTENTS
page page
AUTOMATIC TRANSMISSION - 545RFE
DESCRIPTION........................178
OPERATION..........................179
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - AUTOMATIC
TRANSMISSION.....................179
DIAGNOSIS AND TESTING - PRELIMINARY . 180
DIAGNOSIS AND TESTING - ROAD
TESTING...........................180
DIAGNOSIS AND TESTING - HYDRAULIC
PRESSURE TEST....................181
DIAGNOSIS AND TESTING - AIR CHECKING
TRANSMISSION CLUTCH OPERATION....182
DIAGNOSIS AND TESTING - CONVERTER
HOUSING FLUID LEAK................182
STANDARD PROCEDURE - ALUMINUM
THREAD REPAIR.....................183
REMOVAL............................183
DISASSEMBLY........................185
CLEANING...........................190
INSPECTION.........................190
ASSEMBLY...........................190
INSTALLATION........................197
SCHEMATICS AND DIAGRAMS
HYDRAULIC SCHEMATICS.............199
SPECIFICATIONS
TRANSMISSION.....................220
SPECIAL TOOLS
RFE TRANSMISSION.................221
4C RETAINER/BULKHEAD
DISASSEMBLY........................224
ASSEMBLY...........................224
ADAPTER HOUSING SEAL
REMOVAL............................225
INSTALLATION........................225
BRAKE TRANSMISSION SHIFT INTERLOCK
MECHANISM
DESCRIPTION........................226
OPERATION..........................226
DIAGNOSIS AND TESTING - BRAKE
TRANSMISSION SHIFT INTERLOCK......226
ADJUSTMENTS - BRAKE TRANSMISSION
SHIFT INTERLOCK...................227
FLUID AND FILTER
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - EFFECTS OF
INCORRECT FLUID LEVEL.............228
DIAGNOSIS AND TESTING - CAUSES OF
BURNT FLUID.......................228DIAGNOSIS AND TESTING - FLUID
CONTAMINATION....................228
STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK............................229
STANDARD PROCEDURE - FLUID AND
FILTER REPLACEMENT...............230
STANDARD PROCEDURE - TRANSMISSION
FILL...............................230
GEARSHIFT CABLE
DIAGNOSIS AND TESTING - GEARSHIFT
CABLE.............................231
REMOVAL............................231
INSTALLATION........................231
ADJUSTMENTS - GEARSHIFT CABLE......232
HOLDING CLUTCHES
DESCRIPTION........................233
OPERATION..........................234
INPUT CLUTCH ASSEMBLY
DESCRIPTION........................235
OPERATION..........................235
DISASSEMBLY........................237
ASSEMBLY...........................238
INPUT SPEED SENSOR
DESCRIPTION........................244
OPERATION..........................244
REMOVAL............................244
INSTALLATION........................244
LINE PRESSURE (LP) SENSOR
DESCRIPTION........................245
OPERATION..........................245
REMOVAL............................245
INSTALLATION........................245
LOW/REVERSE CLUTCH
DISASSEMBLY........................246
CLEANING...........................247
INSPECTION.........................247
ASSEMBLY...........................247
OIL PUMP
DESCRIPTION........................248
OPERATION..........................248
STANDARD PROCEDURE - OIL PUMP
VOLUME CHECK.....................249
DISASSEMBLY........................250
CLEANING...........................252
INSPECTION.........................252
ASSEMBLY...........................253
OIL PUMP FRONT SEAL
REMOVAL............................253
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 177

STANDARD PROCEDURE
STANDARD PROCEDURE - FLUID LEVEL
CHECK
Low fluid level can cause a variety of conditions
because it allows the pump to 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 condi-
tions which occur with a low fluid level.
In either case, air bubbles can cause overheating
and/or fluid oxidation, and varnishing. This can inter-
fere with normal valve, clutch, and accumulator opera-
tion. 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 cor-
rect if it is in the HOT region (cross-hatched area) on
the oil level indicator. The fluid level will be approx-
imately at the upper COLD hole of the dipstick at
70É F fluid temperature.
NOTE: Engine and Transmission should be at nor-
mal operating temperature before performing this
procedure.
(1) Start engine and apply parking brake.
(2) Shift the transmission into DRIVE for approxi-
mately 2 seconds.
(3) Shift the transmission into REVERSE for
approximately 2 seconds.
(4) Shift the transmission into PARK.
(5)
Hook up DRBtscan tool and select transmission.
(6) Select sensors.
(7) Read the transmission temperature value.
(8) Compare the fluid temperature value with the
chart. (Fig. 59)
(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.
Fig. 59 Transmission Fluid Temperature Chart
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 229
FLUID AND FILTER (Continued)

STANDARD PROCEDURE - FLUID AND FILTER
REPLACEMENT
For proper service intervals (Refer to LUBRICA-
TION & MAINTENANCE/MAINTENANCE SCHED-
ULES - DESCRIPTION).
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 trans-
mission allowing the fluid to drain into drain pan.
(6) Hold up pan and remove remaining bolts hold-
ing pan to transmission.
(7) While holding pan level, lower pan away from
transmission.
(8) Pour remaining fluid in pan into drain pan.
(9)
Remove screw holding filter to valve body (Fig. 60).
(10) Separate filter from valve body and oil pump
and pour fluid in filter into drain pan.
(11) Remove and discard the oil filter seal from the
bottom of the oil pump.
(12) If replacing the cooler return filter, use Oil
Filter Wrench 8321 to remove the filter from the
transmission.
(13) Dispose of used trans fluid and filter(s) prop-
erly.
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 problemunless 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 mag-
net.
(2) Using a suitable gasket scraper, clean original
sealing material from surface of transmission case
and the transmission pan.
INSTALLATION
(1) Install a new primary oil filter seal in the oil
pump inlet bore. Seat the seal in the bore with the
butt end of a hammer, or other suitable tool.
CAUTION: The primary oil filter seal MUST be fully
installed flush against the oil pump body. DO NOT
install the seal onto the filter neck and attempt to
install the filter and seal as an assembly. Damage to
the transmission will result.
(2) Place replacement filter in position on valve
body and into the oil pump.
(3) Install screw to hold filter to valve body (Fig.
60). Tighten screw to 4.5 N´m (40 in. lbs.) torque.
(4) Install new cooler return filter onto the trans-
mission, if necessary. Torque the filter to 14.12 N´m
(125 in.lbs.).
(5) Place bead of MopartRTV sealant onto the
transmission case sealing surface.
(6) Place pan in position on transmission.
(7) Install bolts to hold pan to transmission.
Tighten bolts to 11.8 N´m (105 in. lbs.) torque.
(8) Lower vehicle and fill transmission with
MopartATF +4, type 9602 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 MopartAT F
+4 to transmission:
(a) If only fluid and filter were changed, add10
pints (5 quarts)of ATF +4 to transmission.
(b) If transmission was completely overhauled,
torque converter was replaced or drained, and
cooler was flushed, add24 pints (12 quarts)of
ATF +4 to transmission.
(3) Check the transmission fluid (Refer to 21 -
TRANSMISSION/TRANSAXLE/AUTOMATIC -
45RFE/FLUID - STANDARD PROCEDURE) and
adjust as required.
Fig. 60 Transmission Filters - 4X4 Shown
1 - PRIMARY OIL FILTER
2 - COOLER RETURN FILTER
3 - COOLER RETURN FILTER BYPASS VALVE
4 - VALVE BODY
21 - 230 AUTOMATIC TRANSMISSION - 545RFEWJ
FLUID AND FILTER (Continued)

STANDARD PROCEDURE - OIL PUMP VOLUME
CHECK
Measuring the oil pump output volume will deter-
mine if sufficient oil flow to the transmission oil
cooler exists, and whether or not an internal trans-
mission failure is present.
Verify that the transmission fluid is at the proper
level. Refer to the Fluid Level Check procedure in
this section. If necessary, fill the transmission to the
proper level with MopartATF +4, type 9602, Auto-
matic Transmission Fluid.
(1) Disconnect theTo coolerline at the cooler
inlet and place a collecting container under the dis-
connected line.CAUTION: With the fluid set at the proper level,
fluid collection should not exceed (1) quart or inter-
nal damage to the transmission may occur.
(2) Run the engineat 1800 rpm, with the shift
selector in neutral. Verify that the transmission fluid
temperature is below 104.5É C (220É F) for this test.
(3) If one quart of transmission fluid is collected in
the container in 30 seconds or less, oil pump flow vol-
ume is within acceptable limits. If fluid flow is inter-
mittent, or it takes more than 30 seconds to collect
one quart of fluid, refer to the Hydraulic Pressure
tests in this section for further diagnosis.
(4) Re-connect theTo coolerline to the transmis-
sion cooler inlet.
Fig. 90 Oil Pump Reaction Shaft
1 - PUMP HOUSING 4 - SEAL RING (5)
2 - SEAL 5 - REACTION SHAFT SUPPORT
3 - OIL FILTER SEAL 6 - PUMP VALVE BODY
WJAUTOMATIC TRANSMISSION - 545RFE 21 - 249
OIL PUMP (Continued)