4F50N Water intrusion 2003- up

2008-08-27, TCRA Email Forum

2003-UP Windstar, Freestar, with 4F50N.

Since 2 months, I received many call about lining problem in Torque and Transmission ( lining goes OFF from steel part )

. And also you will see some white creamy stuff in top of the side pan.

We found the problem on this one,

2003 and up, Ford install a new dipstick tube on this unit and is a 2 piece design, where the top tube goes

into the other one, It sealed by a ”O” ring, but when rain come from top of windshield, it falling down by the wiper shaft and goes right in the section where the 2 tube is connected, and the ”O” ring is not enough big to sealed the dipstick tube.

Water in Transmission = big problem !!!!!!!!!!!!!!!!!!!!!

FIX, silicone on the ”O” ring, and also we put a Electrical shield on tube too.

I hope is gonna help everyone.

Serge Martin
Service Technique
Matech Bta inc.

Hey Serge, water in a transmission is a bad thing, but you had mentioned that your linings came off in both the torque and the trans, if I am not mistaken. Water on its own should not cause this problem, it would explain the milky fluid, but not the line failure. The only thing that I know that can cause both dramatic clutch line de-bonding and milky fluid, is antifreeze contamination, the glycol in antifreeze attacks the glue on the frictions and lockup lining. You had mentioned rain water going inside the trans through a poorly sealed dipstick, Just a thought.

Peter Cifuentes
Converter Man Limited

Hi Peter,

We already by-passed the radiator, and 2 week after, Same problem !!! lining from every clutch and torque converter Completely off,

It’s look like, anti-freeze and water do the same result.

Serge Martin
Service Technique
Matech Bta inc.800-567-0929


Go here

Raybestos Powertrain one of our sponsors has an excellent article on water.



I’ve waited all day for someone to say this….
There is antifreeze in washer fluid. If rainwater can get in so can
washer fluid..

Pat Kinney
Product Line Manager
Allison Products
Torque Converter Products