Chrysler New Yorker. Manual — part 284

(7) Allow vehicle wheels to turn and increase

throttle opening to achieve an indicated vehicle speed
of 50 mph.

(8) Verify the torque converter clutch is applied

mode using the RPM display of the DRB scan tool.

(9) Torque converter clutch on pressure should be

60-90 psi.

TEST SIX-SELECTOR IN R

NOTE: This test checks the reverse clutch hydrau-
lic circuit.

(1) Attach gauge to the reverse and LR clutch tap.
(2) Move selector lever to the R position.
(3) Read reverse clutch pressure with output sta-

tionary (foot on brake) and throttle opened to achieve
1500 rpm.

(4) Reverse and LR clutch pressure should read

165 to 235 psi.

TEST RESULT INDICATIONS

(1) If proper line pressure is found in any one test,

the pump and pressure regulator are working prop-
erly.

(2) Low pressure in all positions indicates a defec-

tive pump, a clogged filter, or a stuck pressure regu-
lator valve.

(3) Clutch circuit leaks are indicated if pressures

do not fall within the specified pressure range.

(4) If the overdrive clutch pressure is greater than 5

psi in Step 7 of Test Three, a worn reaction shaft seal
ring or a defective solenoid assembly is indicated.

(5) If the underdrive clutch pressure is greater

than 5 psi in Step 5 of Test 2A, a defective solenoid
assembly or TCM is the cause.

CLUTCH AIR PRESSURE TESTS

Inoperative clutches can be located by substituting

air pressure for fluid pressure. The clutches may be
tested by applying air pressure to their respective
passages after the valve body has been removed. Use
Special Tool 6599-1 and 6599-2 to perform test (Fig.
7).

To make air pressure tests, proceed as follows:

NOTE: The compressed air supply must be free of
all dirt and moisture. Use a pressure of 30 psi.

Remove oil pan and valve body. See Valve body

recondition.

Apply air pressure to the holes in the special tool,

one at a time.

Listen for the clutch to apply. It will give a slight

thud sound. If a large amount of air is heard escap-
ing, the transaxle must be removed from vehicle, dis-
assembled and all seals inspected.

OVERDRIVE CLUTCH

Apply air pressure to the overdrive clutch apply

passage and watch for the push/pull piston to move
forward. The piston should return to its starting
position when the air pressure is removed.

UNDERDRIVE CLUTCH

Because this clutch piston cannot be seen, its oper-

ation is checked by function. Air pressure is applied
to the low/reverse or the 2/4 clutches. This locks the
output shaft. Use a piece of rubber hose wrapped
around the input shaft and a pair of clamp-on pliers
to turn the input shaft. Next apply air pressure to
the underdrive clutch (Fig. 8). The input shaft should
not rotate with hand torque. Release the air pressure
and confirm that the input shaft will rotate.

REVERSE CLUTCH

Apply air pressure to the reverse clutch apply pas-

sage and watch for the push/pull piston to move rear-
ward. The piston should return to its starting
position when the air pressure is removed.

2/4 CLUTCH

Apply air pressure to the feed hole located on the

2/4 clutch retainer. Look in the area where the 2/4
piston contacts the first separator plate and watch
carefully for the 2/4 piston to move rearward. The
piston should return to its original position after the
air pressure is removed.

LOW/REVERSE CLUTCH

Apply air pressure to the low/reverse clutch feed

hole passage. Look in the area where the low/reverse
piston contacts the first separator plate. Watch care-
fully for the piston to move forward. The piston
should return to its original position after the air
pressure is removed.

FLUID LEAKAGE

The 42LE is a dual sump transaxle. The transaxle

uses both automatic transaxle fluid (ATF) for the
main sump and hypoid gear lube for the differential
sump. When diagnosing a leak, it is important to dis-
tinguish which type of fluid is leaking. Factory fill
ATF is dyed red, while differential hypoid oil is
brown in color and has a distinctive odor.

There are two seals at the boundary of the two

sumps. There is a weep hole in the right side of the
transaxle case (Fig. 9) which vents the area between
the two seals. If oil is leaking from the weep hole,
there is at least one seal leaking. Never plug the
weep hole to correct a leaking condition. Plugging the
weep hole could result in contaminating one or both
transaxle sumps, low oil level, poor transaxle perfor-
mance or transaxle failure. In order to correctly

300M

TRANSAXLE

21 - 9

DIAGNOSIS AND TESTING (Continued)

repair this type of leak the transaxle must be
removed from the vehicle and both transfer shaft
seals replaced. Refer to Transfer Shaft Seal Replace-
ment procedure in this section.

FLUID LEAKAGE-TORQUE CONVERTER
HOUSING AREA

(1) Check for source of leakage. Fluid leakage from

the torque converter area may originate from an
engine oil leak, a differential oil leak or an ATF oil
leak. The area should be examined closely.

(2) Prior to removing the transaxle, perform the

following checks:

• When leakage is determined to be automatic

transmission fluid, check fluid level prior to removal
of the transaxle and torque converter.

42LE PRESSURE CHECK SPECIFICATIONS

Fig. 7 Air Pressure Test Plate

Fig. 8 Testing Underdrive Clutch

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TRANSAXLE

300M

DIAGNOSIS AND TESTING (Continued)

• High oil level can result in oil leakage out the

vent. If the fluid level is high, adjust to proper level.

• After performing this operation, inspect for leak-

age. If a leak persists, perform the following opera-
tion on the vehicle. This will determine if it is the
torque converter or transaxle that is leaking.

TORQUE CONVERTER LEAKAGE

Possible sources of torque converter leakage are:
• Torque converter weld leaks at the outside

(peripheral) weld.

• Torque converter hub weld.

NOTE: Hub weld is inside and not visible. Do not
attempt to repair. Replace torque converter.

FLUID LEAKAGE—DIFFERENTIAL HOUSING
AREA

The differential uses 75W-90 fuel saving petroleum

based hypoid gear lube. It can be distinguished from
ATF by its brown color (ATF is dyed red). Also gear
lube has a distinctive odor (hypoid smell).

(1) If it is suspected that the leakage is gear lube,

check the differential for proper fluid level. High oil
level can result in leakage from the differential vent.

CAUTION: A crushed vent baffle will cause oil to
leak from vent hose.

(2) If fluid level is correct, add 1/4 to 1/2 ounce of

leak detecting florescent dye to the differential.

(3) Clean the suspect area of the transaxle with

solvent.

(4) Road test the vehicle until the leak reoccurs.

(5) Using a black light determine the source of the

leak and repair as required.

(6) Do not add oil dye to both the ATF sump and

the differential sump at the same time. This can
cause confusion when trying to pinpoint a leak
source.

SHIFTER/IGNITION INTERLOCK

COLUMN SHIFT

If the interlock cable breaks while the shifter is in

the park position, the shifter will remain in park.
Should the interlock cable break when the shifter is
in neutral, the operator won’t be able to shift to park.
In either case, replace and adjust the interlock cas-
sette or interlock cable.

FLOOR SHIFT

(1) With the floor shifter in Park, place the igni-

tion key in the Lock position. The operator should
not be able to remove the shifter from Park (button
on shifter won’t depress) when the ignition key is in
the Lock position.

(2) Turn the ignition key to the Run position. With

the ignition key in the Off or Run position, the oper-
ator should be able to shift into any gear position.
With the shifter in a gear selection other than park,
the operator should not be able to remove the igni-
tion key.

(3) Return the shifter to the Park position. The

operator should be able to remove the key after plac-
ing it in the Lock position.

(4) If the interlock system does not work as

described in the above steps, check the system for
incorrect adjustment or a binding cable. Refer to the
Adjustment procedure or the Removal procedure as
necessary.

SHIFT POSITION INDICATOR

The Transmission Range Sensor (TRS) on the valve

body, sends a signal to the TCM on the position of
the transaxle manual valve lever. The TCM receives
the switch signal and processes the data. The TCM
sends the Shift Lever Position (SLP) information to
the BCM via the PCI bus. The BCM then outlines
the appropriate shifter position indicator on the
instrument cluster.

If a problem arises with the shifter position indica-

tor, consult the following chart for diagnostic infor-
mation. If the malfunction cannot be corrected using
the chart, consult the proper diagnostic manual.

To replace the shifter position indicator, refer to

Group

8E,

Instrument

Panel

And

Gauges.

Fig. 9 Weep Hole Location

300M

TRANSAXLE

21 - 11

DIAGNOSIS AND TESTING (Continued)

CONDITION

POSSIBLE CAUSE

ALL PRND3L DISPLAY
LIGHTS

9

ON

9

IN P&N

GEAR POSITIONS

Check wiring and
connectors

Faulty TRS

Faulty manual lever

ALL DISPLAY LIGHTS

9

ON

9

IN ALL GEAR

POSITIONS

Check wiring &
connectors

Faulty TRS

Faulty manual lever

J1850 bus communication
malfunction

ALL DISPLAY LIGHTS

9

OFF

9

Normal transient condition
between P&R and R&N
gear positions

Check shift lever linkage

Body controller
malfunction

Check wiring and
connectors

Faulty cluster

ALL DISPLAY LIGHTS

9

OFF

9

ACCOMPANIED

BY A

9

NO BUS

9

MESSAGE

J1850 bus communication
malfunction

DISPLAY LIGHTS OUT
OF SEQUENCE WITH
SHIFT LEVER

Check wiring and
connectors

Faulty TRS

Faulty manual lever

J1850 bus communication
malfunction

AUTOSTICK

The autostick feature will be deactivated if one of

the following conditions occur:

• DIAGNOSTIC TROUBLE CODE 28–PRNDL

Error–usually accompanied by all PRNDL lights
turning on in Park and Neutral. This will result in a
trouble code 28 if three such errors are detected after
any one “key–on”.

• DIAGNOSTIC TROUBLE CODE 70–Autostick

Switch Error

• DIAGNOSTIC TROUBLE CODE 71–High Pow-

ertrain Temperature–(Transmission oil temperature
> 275° F) or (Engine coolant temperature > 255° F).

Autostick will be reactivated when the condition

that caused deactivation no longer exists (The Diag-
nostic Trouble Codes may remain in memory up to 75
starts after the fault was initially set). The following
conditions must be met to reactivate Autostick after
a high temperature fault:

• Acceptable Powertrain Temperature = (Trans-

mission Oil Temperature <255° F) and (Engine Cool-
ant Temperature <240° F).

42LE FOUR SPEED TRANSAXLE ON-BOARD
DIAGNOSTICS

GENERAL INFORMATION

This manual is designed to help the technician

repair a 42LE four speed transaxle with the use of
on-board diagnostics.

NOTE: Chrysler Corporation has developed a com-
plete set of diagnostic manuals. These manuals
cover the diagnosis of a 42LE transaxle. They have
been designed to make transaxle diagnosis accu-
rate and simple. Use these manuals with the DRB
scan tool and the latest cartridge, when diagnosing
transaxle problems.

SERVICE PROCEDURES

FLUID AND FILTER CHANGE-TRANSMISSION
SUMP

NOTE: Only fluids of the type labeled Mopar ATF
Plus 3 (Automatic Transmission fluid) Type 7176
should be used. A filter change should be made at
the time of the oil change. The magnet (on the
inside of the oil pan) should also be cleaned with a
clean, dry cloth.

NOTE: If the transaxle is disassembled for any rea-
son, the fluid and filter should be changed.

(1) Raise vehicle on a hoist (See Lubrication,

Group 0). Place a drain container with a large open-
ing, under transaxle oil pan.

(2) Loosen pan bolts and tap the pan at one corner

to break it loose allowing fluid to drain, then remove
the oil pan.

(3) Install a new filter and o-ring on bottom of the

valve body and tighten retaining screws to 5 N·m (40
in. lbs.).

(4) Clean the oil pan and magnet. Reinstall pan

using new Mopar Silicone Adhesive sealant. Tighten
oil pan bolts to 19 N·m (165 in. lbs.).

(5) Pour four quarts of Mopar ATF Plus 3 (Auto-

matic Transmission Fluid) Type 7176 through the
dipstick opening.

(6) Start engine and allow to idle for at least one

minute. Then, with parking and service brakes
applied, move selector lever momentarily to each
position, ending in the park or neutral position.

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TRANSAXLE

300M

DIAGNOSIS AND TESTING (Continued)