Transmission Fluid Cooler Flow Test

WARNING: This page is about a different car, the 2004 Lincoln LS. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: The engine idle, fluid level and line pressure must be within specification before carrying out this test.

For additional information on engine idle diagnosis, refer to the INTRODUCTION .
For additional information on fluid level check, refer to TRANSMISSION FLUID LEVEL CHECK in this section.
For additional information on line pressure, refer to SPECIAL TESTING PROCEDURES in this section.

With the vehicle in PARK position it on a hoist. For additional information, refer to LIFTING .
Prior to carrying out this test check to see if the vehicle is equipped with a in-line fluid filter. If the vehicle is equipped with a in-line fluid filter it must be removed and discarded.

Fig 1: Removing In-Line Fluid Filter
Courtesy of FORD MOTOR CO.
Using a 3/16 inch Allen key, hold the large drain plug with a wrench and remove the small (center) fluid level indicating plug.

Fig 2: Removing Small (Center) Fluid Level Indicating Plug
Courtesy of FORD MOTOR CO.
Install the special tool into the pan.

Fig 3: Installing Special Tools Into Pan
Courtesy of FORD MOTOR CO.
Remove the cooler return line (upper line) from the fitting on the transmission case.

Fig 4: 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.
Lower the vehicle.
Start the engine and run it at idle.
With the engine running, the vehicle in PARK position it on a hoist. For additional information, refer to 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 is observed, approximately 208 ml (7 oz) will be in the measuring container. The test is now complete. Reconnect the cooler line and install the fluid fill plug.

Fig 5: Reconnecting Cooler Line
Courtesy of FORD MOTOR CO.
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).
Repeat Steps 10-11. If the flow is not approximately 208 ml (7 oz) in 15 seconds, install a new fluid cooler and flush the fluid cooler tubes. If the flow from the case is still not adequate, repair the main control, pump and/or torque converter as required.
Once an adequate flow has been established, install a new in-line fluid filter, if previously removed.
After all the repairs have been made, carry out the fluid level check. For additional information, refer to TRANSMISSION FLUID LEVEL CHECK in this section.