This 2006 Ford Expedition came in with the complaint that the transmission would shift through the gears and the torque converter solenoid would lock up below 25 mph. There was a shudder present at low speed due to the condition. The problem would also go away sometimes. A transmission shop and the local Ford dealership could not help the customer and my shop was recommended. I am definitely not a transmission expert by any means but a little bit of research led me to this answer. Sadly, there was a Ford Motor Company TSB on the subject. The TSB applies to the following vehicles.
2005-2010 Crown Victoria
2005-2010 E-150, E-250, E-350, F-150
2005-2010 Town Car
2006-2008 Mark LT
2005-2010 Grand Marquis
I was not going to take a chance on getting transmission fluid in my camera so pictures are limited.
The number 7 ball check valve is listed as the cause of the problem in the TSB and it is located in the upper right hand quadrant in the picture below.
I am pointing to the #7 check ball in the next picture. The perspective has rotated 90 degrees CCW in relation to the picture above.
The check ball is missing about 50 percent of it’s surface area.
The old check ball is the lower one.
The following part numbers are needed for the repair. The check ball comes in a package of seven. The gaskets were available individually.
Part Number Part Description
EOAZ-7E195-B Ball Check
1L3Z-7C155-AA Gasket – Valve Body Upper
1W7Z-7D100-AB Gasket – Valve Body Lower
The main pan gasket is reusable. You do need to wipe it dry and use an inch pound torque wrench to install the pan. The gasket without the tree large holes is laid down on the valve body.
Then the large plate that covers the entire valve body is installed. The two round covers are installed o top of the plate. The torque wrench is also needed to install the bolts holding the plates.
The second gasket is installed over the plates.
The valve body is now ready to install back into the transmission. There are specific tightening patterns that need to be followed along with the proper torque specifications. Two things that are helpful to know are that you have to pay attention to the shifter linkage position in relation to the plunger/rod on the driver’s side of the valve body.
Also there is a screen above the valve body in the left forward corner of the transmission that has to be held in place with a tool as the valve body is put back into the transmission. I had this piece of scrap metal around and it is what I used. All of the metal above my finger is not needed. Just the metal below and to the right.
Make sure there are no rough edges that will grab on the gasket material.
I strongly recommend using a traditional repair manual to do this transmission service. I simply wanted to add a few real world pictures and a bit of advise. Of course an new filter and fluid will be needed as well.
Below is a link to the actual Ford TSB that I found on another site.