Chrysler Town & Country/Voyager, Dodge Caravan, Plymouth Voyager. Manual — part 85
FLUID LEVEL AND CONDITION
The transmission and differential sump have a
common oil sump with a communicating opening
between the two.
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. This will assure complete oil level stabi-
lization between differential and transmission.
The fluid should be at normal operating temperature
(approximately 82 C. or 180 F.). The fluid level is
correct if it is in the ‘‘HOT’’ region (cross-hatched area)
on the oil level indicator.
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 transaxle has too much fluid, the gears
churn up foam and cause the same conditions which
occur with a low fluid level.
In either case, the air bubbles can cause over heat-
ing, fluid oxidation, and varnishing, which can inter-
fere with normal valve, clutch, and accumulator opera-
tion. Foaming can also result in fluid escaping from the
transaxle vent where it may be mistaken for a leak.
Along with fluid level, it is important to check the
condition of the fluid. When the fluid smells burned,
and is contaminated with metal or friction material
particles, a complete transaxle overhaul is needed. Be
sure to examine the fluid on the dipstick closely. If
there is any doubt about its condition, drain out a
sample for a double check.
After the fluid has been checked, seat the dipstick
fully to seal out water and dirt.
SELECTION OF LUBRICANT
It is important that the proper lubricant be used in
these transmissions. MOPAR
t ATF PLUS (Automatic
Transmission Fluid-Type 7176) should be used to aid in
assuring optimum transmission performance. Fluids of
the type labeled DEXRON II Automatic Transmission
Fluid is not recommended. DEXRON II can be used
only if the recommended fluid is not available. If more
than a small amount of Dexron fluid is used, shutter or
shift quality problems may be encountered. It is impor-
tant that the transmission fluid be maintained at the
prescribed level using the recommended fluids.
SPECIAL ADDITIVES
Chrysler Corporation does not recommend the addi-
tion of any fluids to the transmission, other than the
automatic transmission fluid listed above. An excep-
tion to this policy is the use of special dyes to aid in
detecting fluid leaks. The use of transmission sealers
should be avoided, since they may adversely affect
seals.
FLUID AND FILTER CHANGE
When the factory fill fluid is changed, only fluids of
the type labeled MOPAR
t ATF PLUS (Automatic
Transmission fluid) Type 7176 should be used. A filter
change should be made at the time of the oil change.
Also the magnet (on the inside of the oil pan) should be
cleaned with a clean, dry cloth.
If the transaxle is disassembled for any reason, the
fluid and filter should be changed.
FLUID DRAIN AND REFILL
(1) Raise vehicle on a hoist (See Lubrication, ‘‘Group
0’’). Place a drain container with a large opening, 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.
(4) Clean the oil pan and magnet. Reinstall pan
using Mopar
t Silicone Rubber Adhesive Sealant or
equivalent. Tighten oil pan bolts to 19 N
Im (165 in.
lbs.).
(5) Pour four quarts of MOPAR
t ATF PLUS (Auto-
matic Transmission Fluid) Type 7176 through the fill
tube.
(6) Start engine and allow to idle for at least one
minute. Then, with parking and service brakes ap-
plied, move selector lever momentarily to each posi-
tion, ending in the park or neutral position.
(7) Add sufficient fluid to bring level to 1/8 inch
below the ADD mark (Fig. 3).
Recheck fluid level after transaxle is at normal
operating temperature. The level should be in the HOT
region (Fig. 3).
To prevent dirt from entering transaxle, make cer-
tain that dipstick is seated into the dipstick fill tube
(Fig. 4).
Fig. 3 Oil Level Indicator
.
TRANSAXLE
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ROAD TEST
Prior to performing a road test, be certain that the
fluid level and condition, and control cable adjustment
have been checked and approved.
During the road test, the transaxle should be oper-
ated in each position to check for slipping and any
variation in shifting.
If vehicle operates properly at highway speeds, but
has poor through-gear acceleration, the torque con-
verter stator overrunning clutch may be slipping. If
through-gear acceleration is normal, but abnormally
high throttle opening is required to maintain highway
speeds, the torque converter stator clutch may have
seized. Both of these stator defects require replacement
of the torque converter.
In most cases, the clutch that is slipping can be
determined by noting the transaxle operation in all
selector positions. Then comparing which internal
units are applied in those positions. The ‘‘Elements in
Use Chart’’ provides a basis for road test analysis.
The process of eliminating can be used to detect any
unit which slips and to confirm proper operation of
good units. However, although road test analysis can
usually diagnose slipping units, the actual cause of the
malfunction usually can not be decided. Practically any
condition can be caused by leaking hydraulic circuits or
sticking valves.
Fig. 4 Oil Level Indicator Location
ELEMENTS IN USE AT EACH POSITION OF THE SELECTOR LEVER
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TRANSAXLE
.
HYDRAULIC PRESSURE TESTS
Pressure testing is a very important step in the
diagnostic procedure. These tests usually reveal the
cause of most transaxle problems.
Before performing pressure tests, be certain that
fluid level and condition, and shift cable adjustments
have been checked and approved. Fluid must be at
operating temperature 66 to 93 degrees C. (150 to 200
degrees F.).
Install an engine tachometer, raise vehicle on hoist
which allows front wheels to turn, and position ta-
chometer so it can be read.
Attach 150 psi gauges to ports required for test being
conducted. A 300 psi gauge (C-3293) is required for
reverse pressure test.
Test port locations are shown in (Figure 1).
TEST ONE (SELECTOR IN ‘‘L’’ 1ST GEAR)
(1) Attach pressure gauge to the low/reverse clutch
tap.
(2) Move selector lever to the L position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
to 20 mph.
(4) Low/reverse clutch pressure should read 115 to
145 psi.
(5) This test checks pump output, pressure regula-
tion and condition of the low/reverse clutch hydraulic
circuit and shift schedule.
TEST TWO (SELECTOR IN ‘‘3’’ 2ND GEAR)
(1) Attach gauge to the underdrive clutch tap.
(2) Move selector lever to the ‘‘3’’ position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 30 mph.
(4) Underdrive clutch pressure should read 110 to
145 psi.
(5) This test checks the underdrive clutch hydraulic
circuit as well as the shift schedule.
TEST THREE (OVERDRIVE CLUTCH CHECK)
(1) Attach gauge to the overdrive clutch tap.
(2) Move selector lever to the ‘‘circle D’’ position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 20 mph.
(4) Overdrive clutch pressure should read 74 to 95
psi.
(5) Move selector lever to the ‘‘3’’ position and in-
crease indicated vehicle speed to 30 mph.
(6) The vehicle should be in second gear and over-
drive clutch pressure should be less than 5 psi.
(7) This test checks the overdrive clutch hydraulic
circuit as well as the shift schedule.
TEST FOUR (SELECTOR IN ‘‘CIRCLE D’’ OVER-
DRIVE GEAR)
(1) Attach gauge to the 2/4 clutch tap.
(2) Move selector lever to the ‘‘circle D’’ position.
(3) Allow vehicle front wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 30 mph.
(4) The 2/4 clutch pressure should read 75 to 95 psi.
(5) This test checks the 2/4 clutch hydraulic circuit.
TEST FIVE (SELECTOR IN ‘‘CIRCLE D’’ OVER-
DRIVE LOCKUP)
(1) Attach gauge to the lockup off pressure tap.
(2) Move selector lever to the ‘‘circle D’’ position.
(3) Allow vehicle wheels to turn and increase
throttle opening to achieve an indicated vehicle speed
of 50 mph.
CAUTION: Both wheels must turn at the same speed.
(4) Lockup off pressure should be less than 5 psi.
(5) This test checks the lockup clutch hydraulic
circuit.
TEST SIX (SELECTOR IN REVERSE)
(1) Attach gauge to the reverse clutch tap.
(2) Move selector lever to the reverse position.
(3) Read reverse clutch pressure with output sta-
tionary (foot on brake) and throttle opened to achieve
1500 rpm.
(4) Reverse clutch pressure should read 165 to 235
psi.
(5) This test checks the reverse clutch hydraulic
circuit.
Fig. 1 Pressure Taps
.
TRANSAXLE
21 - 91
TEST RESULT INDICATIONS
(1) If proper line pressure is found in any one test,
the pump and pressure regulator are working properly.
(2) Low pressure in all positions indicates a defec-
tive pump, a clogged filter, or a stuck pressure regula-
tor 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 (6) of Test Three, a worn reaction shaft seal
ring is indicated.
CLUTCH AIR PRESSURE TESTS
Inoperative clutches can be located using a series of
tests by substituting air pressure for fluid pressure
(Figs. 2 and 3). The clutches may be tested by applying
air pressure to their respective passages after the valve
body has been removed and Tool 6056 has been in-
stalled. To make air pressure tests, proceed as follows:
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).
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 posi-
tion when the air pressure is removed.
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.
PRESSURE CHECK SPECIFICATIONS
Fig. 2 Air Pressure Test Plate
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TRANSAXLE
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