I took my truck for 200 mile round trip yesterday. I got to my destination OK, but on the return trip, I came upon an accident and backed up traffic. After a while the traffic started to move, and I was on my way again. I went a few miles and my E4OD trans started to slip. There was a cloud of oil behind the truck. I was able to pull off the highway and into a parking lot.

Within a few minutes there was a puddle of transmission oil on the ground. My tailgate was coated with the stuff.

I got a tow home, and the tow operator suggested that my trans overheated in the traffic, and blew a seal. The oil seems to come from the area of the front seal. He also said that I could probably fill it with oil, and drive it after it had cooled, but the seal will need to be replaced.

When, I got the truck home, I pulled it into my garage, and it was not leaking.

I intend to pull the trans and get it rebuilt, but I want to get all the upgrades possible. This is a pre-95 E4OD.

What parts should be upgraded to improve the reliability of this trans? I don't do any towing, but I have a very high performance motor capabile of over 500 ft-lbs of torque.

 

The first part that needs upgrading is the torque converter hub seal. That's the one that leaks when it gets too hot. There is an aftermarket seal made from Viton that works MUCH better than stock.

What do you have for transmission cooling?

 

I have a water cooler in the bottom of my radiator. It's the same one that I used for years with my C6. There is no external cooler.

What are the chances that the trans is OK, and just needs fluid? I know that the trans has to come out, because I have had other issues, but I am going for cataract surgery next week, and will not be able to R&R the trans for a while.

I am thinking about stockpiling parts, such as a new center bearing support etc.

 

The chances are excellent that the trans is not hurt. If the trans is out change the torque converter hub seal.

I'd also add a really good air to oil cooler. One from a 6.0L truck is the best one you can get.

 

Mark,

I'll look for an air trans cooler. In the meantime I'll refill the trans, and see if it leaks bad.

My other problem, is that it will not always shift into D1, both from Neutral, or sometimes when I coast to a stop. It does go into D1 at idle when manually put into 2nd, then shifted into Drive. I'm using a Baumann Controller.

 

I don't know anything about the Baumann controller. It could be that, or it could be a sticking shift valve in the valve body.

 

I swap the Baumann Controller between this truck and my '83. It works fine there. Unless it's a harness problem, I think that it's a sticking valve or bad solenoid.

Is the Torque Converter Hub Seal in the trans, or in the converter?

 

It is at the torque converter/transmission interface. It seals between the converter hub and the pump.

 

I refilled the trans & went for a short ride. Except for the D1 problem, it shifted right, and doesn't seem to be leaking any oil.

I saw an oil cooler for a 6.0 on Ebay, but it seems to be an engine oil cooler. Is there 2 oil coolers on that truck?

What fittings does the 6.0 oil cooler use? My truck is plumbed with -6AN hose & fittings. I can adapt to Pipe or Flare fittings, but those OEM fittings would make a problem. I'd rather get a Universal aftermarket cooler with common fittings.

 

The 6.0L does have an engine oil cooler, too. I don't know what the fittings are.
If you get an aftermarket cooler a stacked plate cooler works FAR better than a tube and fin.