Chrysler Concorde 1993, Service Manual, Page: 616 / 820

(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 in the differential is correct, add
1/4 to 1/2 ounce of leak detecting florescent dye to
the differential fluid.
(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.
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.
AIR PRESSURE TEST OF TRANSAXLE SUMP
It may be necessary to air pressure test the tran-
saxle to pinpoint the leak. The following two sections
describe the recommended procedure for pressure
testing the ATF side and the differential side of the
transaxle.
Transaxle temperature may be a factor in oil leaks,
therefore some leaks may not show-up during air
pressure testing.
AUTOMATIC TRANSMISSION FLUID SIDE
Fabricate equipment needed for test as shown in
Figures 6 and 7.
The transaxle should be prepared for pressure test
as follows after removal of the torque converter:
(1) Plug dipstick tube and plug oil cooler line fittings.
CAUTION: Prevent manual shaft rotation during in-
stallation and removal.
(2) With rotary motion, install converter hub seal
cup over input shaft, and through the converter hub
seal. The cup must bottom against the pump gear
lugs. Secure with cup retainer strap using starter up-
per hole and opposite bracket hole.
(3) Plug cooler lines.
(4) Remove the remote vent hose from the main
sump vent fitting. Then attach and clamp hose from
nozzle of tool C-4080 or 7700 to the vent fitting.
CAUTION: Do not, under any circumstances, pres-
surize a transaxle to more than 10 psi.
(5) Pressurize the transaxle using Tool C-4080 or
7700 until the pressure gauge reads 8 psi. Position
transaxle so that pump housing and case front may
be covered with soapy solution of water. Leaks are
sometimes caused by porosity in the case or pump
housing.
If a leak source is located, that part and all associ-
ated seals, O-rings, and gaskets should be replaced
with new parts.
TRANSAXLE DIFFERENTIAL SUMP SIDE
(1) Leave stub shafts secured in the differential.
(2) Remove the remote vent hose from the differen-
tial vent fitting. Then attach and clamp hose from
nozzle of tool C-4080 or 7700 to the vent fitting.
CAUTION: Do not, under any circumstances, pres-
surize a transaxle to more than 10 psi.
(3) Pressurize the differential to 8 psi.
(4) Position transaxle so that the differential area
of the transaxle can be covered with a soapy solution
of water. Be sure to cover the case with solution to
check for case porosity.
(5) Look for bubbles to appear in the soapy solu-
tion that was applied to the transaxle. This will in-
dicate the leak point.
If a leak source is located, that part and all associ-
ated seals, O-rings, and gaskets should be replaced
with new parts.
Fig. 6 Torque Converter Hub Seal Cup
Fig. 7 Hub Seal Cup Retaining Strap
TRANSAXLE 21 - 17