Transmission Fluid Cooler Flow Test

SPECIAL TOOL(S)

Transmission Fluid Fill Tool 307-437

NOTE: The engine idle, transmission linkage/cable adjustment, fluid level and line pressure must be within specification before carrying out this test. Refer to AUTOMATIC TRANSAXLE/TRANSMISSION EXTERNAL CONTROLS for adjustments. For additional information on engine idle diagnosis, refer to the INTRODUCTION - GASOLINE . For additional information on fluid level check, refer to AUTOMATIC TRANSAXLE/TRANSMISSION - 5R55S . For additional information on line pressure, refer to AUTOMATIC TRANSAXLE/TRANSMISSION - 5R55S .

Place the transmission range selector lever into PARK.
Raise the vehicle on a hoist and place suitable safety stands under the vehicle. For additional information, refer to JACKING & LIFTING .
Hold the large drain plug with a wrench, and remove the small (center) fluid level indicating plug using a 3/16-inch Allen key.

Fig 1: Identifying Small (Center) Fluid Level Indicating Plug
Courtesy of FORD MOTOR CO.
Install the special tool into the pan.

Fig 2: Installing Special Tool Into Pan
Courtesy of FORD MOTOR CO.
Remove the cooler return line (upper line) from the fitting on the transmission case.

Fig 3: Removing Cooler Return Line (Upper Line) From Fitting On Transmission Case
Courtesy of FORD MOTOR CO.
Connect one end of a clear hose to the cooler return line and route the other end of the hose to the special tool in the pan.

Fig 4: Connecting One End Of Clear Hose To Cooler Return Line
Courtesy of FORD MOTOR CO.
Remove the safety stands and lower the vehicle.
Start the engine and run it at idle.
With the engine running, raise the vehicle on a hoist and place suitable safety stands under the vehicle. For additional information, refer to JACKING & LIFTING .
Once a steady flow of fluid (without air bubbles) is observed, remove the hose from the special tool and place the hose in a measuring container for 15 seconds. After 15 seconds, place the hose back onto the special tool. Lower the vehicle and turn the engine off. Measure the amount of fluid in the container. If adequate flow was observed, approximately 208 ml (7 oz) will be in the measuring container. The test is complete. Reconnect the cooler line and install the fluid fill plug.
If the flow is not liberal, disconnect the hose from the cooler return line and connect the hose to the cooler inlet (lower fitting) on the transmission case. Reconnect the cooler return line to the case (upper fitting).

Fig 5: Connecting Cooler Return Line To Case With Torque Specification (Upper Fitting)
Courtesy of FORD MOTOR CO.
Repeat Steps 8 through 10. If flow is now approximately 208 ml (7 oz) in 15 seconds, the cooler lines and auxiliary cooler must be cleaned. For additional information, refer to TRANSMISSION FLUID COOLER - BACKFLUSHING AND CLEANING in this article. Carry out this entire test after the backflushing and cleaning procedure. If, after carrying out the backflushing and cleaning procedure, the flow is still not adequate, new cooler lines and/or an auxiliary cooler must be installed. If the flow from the case is still not adequate after the installation of new cooler lines and/or an auxiliary cooler (208 ml [7 oz] in 15 seconds), the pump and/or torque converter may be at fault. Carry out the appropriate procedures for diagnosis and repair in this article.