A/T - A670 and A604, Low Temperature Failures
89chrysler19Models
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 CORRECT OIL FLOW DIRECTION --- THE BYPASS VALVE WILL NOT FUNCTION.
Figure 2:
1. Using thread sealer at all connections, assembly the supplied bypass VALVE tees, and connectors as shown in Figure 2.
Figure 3:
2. Raise vehicle on hoist for working access to the transmission oil cooler hoses routed along the inboard side of the left front frame rail.
3. S/AS Body vehicles: Measure 5-1/2 inches rearward from the front edge of the frame rail and 2 inches up from the bottom of rail (Figure 3) and drill a 1/4 inch diameter hole in the rail.
A/AC Body vehicles: Use existing hole in frame rail.
NOTE: ILLUSTRATION IS TYPICAL FOR A604 HOSE ROUTING. A670 HOSE ROUTING DIFFERS SLIGHTLY, BUT THIS PROCEDURE APPLIES TO BOTH.
Figure 4:
Figure 5:
4. Referring to Figures 4 and 5, follow the cooler hoses routed from the transmission to clearly identify the cooler "in" hose.
5. Place an oil pan under the vehicle to catch oil leakage. (Oil loss will be minimal.)
Figure 6:
6. Pushing the cooler hoses against the frame, cut the cooler "in" hose at the drilled hole (Figure 6) and allow oil to drain.
NOTE: THE HOSES ARE BANDED TOGETHER WITH TAPE AT SEVERAL LOCATIONS. UNWRAP TAPE BANDS, AS REQUIRED, TO ALLOW HOSE FLEXIBILITY FOR CONNECTION TO THE BYPASS VALVE ASSEMBLY.
Figure 1:
7. Slide two of the supplied clamps over the hose ends and install the cooler "in" and connectors of the bypass valve assembly to the cut hose ends.
NOTE: REFER TO FIGURE 1 TO IDENTIFY THE MALE (PIPE NIPPLE) END OF THE VALVE. THIS END OF THE ASSEMBLY MUST BE CONNECTED TO THE COOLER "IN" HOSE.
Figure 7:
Figure 8:
8. Cut the other hose (cooler "out") at the drilled hole, allow oil to drain, and connect the hose ends to the valve assembly connectors in the same manner.
9. Cut the supplied foam tube and wrap it around the bypass valve (Figures 7 and 8).
10. Tighten the supplied "push-in" tie strap around the foam tubing and cut off excess strap.
11. Engage the push-in tie strap in the drilled 1/4 inch hole (Figures 7 and 8).
NOTE: BECAUSE THE HOSES AND HOSE ROUTING DIFFER ON THE 3-SPEED AND 4-SPEED TRANSMISSION, THE VALVE ASSEMBLY MUST BE POSITIONED DIFFERENTLY FOR EACH -- VALVE MOUNTED VERTICALLY FOR THE 4- SPEED AND AT AN ANGLE FOR THE 3-SPEED.
12. Tighten all hose clamps.
13. Install the other supplied tie strap to secure the assembly to the frame rail (Figures 7 and 8). Cut off excess strap.
14. Check and, if necessary, adjust transmission oil level.
POLICY: Reimbursable within the provisions of the warranty.
TIME ALLOWANCE:
Labor Operation No. 21-25-20-91 ---------------- 0.5 Hrs.
FAILURE CODE: 08 - Blocked