Colt L4-1597cc 1.6L DOHC (1989)
Transmission Cooler: All Technical Service Bulletins
A/T - A670 & A604, Low Temperature Failures
Models
1988-89 C/AC and S/AS Bodies
Subject
Low Temperature Transmission Failures - A670 and A604 Transmissions
Index
TRANSMISSION
Date
December 29, 1989
No.
21-28-89
(C21-29-9)
P-29
BODY CODE LEGEND
C/AC DYNASTY/NEW YORKER LANDAU/SALON S/AS CARAVAN/GRAND CARAVAN/CARAVAN C/V VOYAGER/GRAND
VOYAGER/TOWN & COUNTRY
SYMPTOM CONDITION
NOTE:
THIS CONDITION AND REPAIR PROCEDURE IS THE SAME AS RECALL 281T WHICH ONLY INVOLVES VEHICLES
EQUIPPED WITH A TRAILER TOW PACKAGE. THIS SERVICE BULLETIN APPLIES TO MODELS WITHOUT TRAILER TOW.
Under certain extremely cold ambient operating temperatures (-20~ F or colder), automatic transmission fluid may get cold enough to resist flow through
the transmission oil cooler mounted in front of the engine radiator. The transmission may fail due to lack of lubrication from the restriction if the vehicle
is driven long distances at highway speeds.
DIAGNOSIS
This modification should be performed on the subject vehicles that are known to be operating under the above described conditions. Also, the
modification should be performed on vehicles that experience transmission failures suspected to be the result of a restricted oil flow condition. (Lack of
lubrication)
PARTS REQUIRED
Pressure actuated cooler bypass valve package
PN 5252836
REPAIR PROCEDURE:
This repair involves the installation of a pressure actuated bypass valve that will bypass the transmission cooler if it becomes restricted.
Figure 1
NOTE:
THE BYPASS VALVE IS DIRECTIONAL, IF IT IS NOT CONNECTED TO THE TRANSMISSION OIL COOLER HOSES IN THE