Blown E40D Front Seal
 

Driving on the freeway today I started noticing my back window was getting very oily looking, and then I started seeing smoke. Pulled over and there was tranny fluid all over everything underneath my truck. Everyone that has looked at it said it looks like the front seal is leaking. What now? Should I take it to a chain tranny shop? Dealer? Who is likely to give me the best deal on something like that and what should I expect? Am I likely to need to replace the tranny or is this fixable? Anyone know a likely price range for this? Thanks.

The seal itself is probably a $5.00 part. It's the labor. It's been so long since I've had anyone work on my truck I have no idea of labor rates. All you can do is call around. Or consider doing it yourself. It's a straight forward remove and refit job. The seal just pops out and you install the new one. Install the ne fluid and you are ready to go. Good luck.

I have heard that the front seal is much more complicated than the rear. What is involved in replacing it?

The transmission has to be removed and the torque converter removed for access to the front seal. You may have an over heat problem and the fluid is coming out the vent or dipstick tube. That will probably require an overhaul or at least a new torque converter.

Can anyone give me some type of idea what this could cost me for a shop to do? I have never worked on a tranny before so I am guessing this will be out of my league. Am I better off fixing, rebuilding, replacing, etc? What is the best type of shop to take it to? Thanks.

My e4od has done the same thing. It's at my mechanic's right now and he is stumped. It has happened twice to me, about a year apart. Only happened on the interstate after about an hour of sustained driving at speed. After the first time I drove it around town and could not get it to leak. My mechanic could not find anything wrong either. Happened again about a month ago. Same thing, would not leak again when driving around town/ back and forth to work etc. My mechanic thought it might be the front seal but after he got it to leak during a long freeway drive he dosen't that was it.
Any ideas?

The drain back hole behind the seal isn't large enough to handle that much fluid.
The pump must be removed and the hole drilled out.

Does the tranny have to be pulled to fix this? Is this a known problem with all e4od trannys? I can't imagine a flaw of that magnitude slipped by the designers. Is/was there a recall? The first time it happened to me the fluid caught fire on the exhaust.

Thanks,
Russ

It's not only common to the E4OD.
Virtually any model is susceptible to this.
Some are worse, some are better.
The big factor is excess heat generated from towing a load with too much weight or wind resistance, long hills. Excess heat is not only generated from going up hill, the other side of the mountain takes it's toll too.
When you back off the accelerator going down hill there is a lot of turbulence in the convertor.
This turbulence causes lots of heat.
An added external transmission cooler hooked in series with the cooler in the radiator is the safest route.
For maximum cooling get one with an electric pusher fan.


http://members.troublecodes.net/stuart/Fancooler.jpg

Thanks Stuart,

So, are you saying the drain back hole is just a fix but not necessarily the cause of the problem? I can see where sustained driving with a trailer could cause an overheating situation but I wasn't towing anything and I don't think the original poster was either.
By the way what brand is the cooler that you show in your post?

Thanks again,
Russ