I have a 1996 f150 with an E40D.

A few weeks ago I put the truck into 4x4 just to keep the autohubs working during the summer. And the next day the transmission leaked out about 1 quart. It leaked from the bell housing at the inspection (look a like) plug.
I parked it, and my mechanic wouldnt look at it, he kept blowing me off and saying put fluid in it and drive it.

So a week later I put fluid in it, and it was great. It lasted for three weeks.
Yesterday I was going down a minimum maintenance road, so I put it in 4x4. Today nearly 24 hours later and 50 miles later, the trans started leaking fluid out of it. When I say leak fluid, it is like putting the faucet on a slow trickle.

The transmission bell housing temp. was 200 and the fluid I collected as it leaked was 100.

Is the 4x4 thing a coincidence? And what is the likely problem? Thanks

 

In that bellhousing area is your torque converter. That area isn't sealed by any means. And if you had your motor out and removed the torque converter, your tranny shouldn't leak much, if any, fluid (mine didn't). Makes me wonder if you have an issue with your torque converter. I guess it's possible that fluid could come out of where the output shaft is (output shaft = what the torque converter fits on to).

It's certainly not normal, you might want to have that checked out.

 

Ya, that had crossed our minds, but both times that it leaked fluid it shifts perfectly fine.

idk,....worried about how many thousands this is gonna cost.

 

Here is a pic of the old girl. I know you guys love pics so here it is

 

If the leak is at the front, there are 4 possible causes I can thin of the top of my head:

1.- As mentioned before, your TC is leaking, the cause can be a loose TC plug (if it has one), or a failing seal in the TC (either seal or TC failure). Replace the TC with a new or aftermarket unit or tighten the drain plug as needed to correct this.

2.- E4OD overheating: Several things can cause this, including a slipping TC. Overheated ATF will blow through the front seal easily, causing leaks. Improving the ATF cooling system will prevent this, modifying your driving habits could help too.

3.- E4OD front seal failure: Can be caused by overheating, bad installation of either the engine or the transmision and wear. Replacing the broke seal with a new one will correct this.

4.- E4OD sleeve wear: Given enough time, the sleeve that receives the front seal will be worn enough that a new seal won't last much, since even in good condition it won't cover all the area tight enough. There are repair sleeves that you can buy to fix this, and I would recommend replacing the seal together with the sleeve installation. Grinding to prepare the surface and moving to a bigger seal is the other viable correction for this.