T176/T177 Leaks

[Neuner]

My T177 leaks from the rear output assembly.

I've tried to study re-build threads to see if I can figure out what might be allowing the leak and how much work it will involve.

The rear output shaft is tight with no play and the bearings seem like they are in really good working order. I don't have any other issues with this tranny. Are the bearings the oil seal or is there another seal behind it? Attached the closest pics I've found to what I'm looking at.

 

[yellow85cj]

There is no seal on the case of the Transmission . The seal is in the adapter (it seals around the output shaft/input shaft of Dana 300 ).The case is sealed to the adapter. The bearing itself has no seal. The adapter has a weep hole to let you know if the seal in the adapter is leaking.

Will try to find my spare adapter and take some pics in the A.M.

 

[Neuner]

Ok, thanks. I found some schematic pics of the parts and I think I see what you are referring to. Mine didn't have a seal at the adapter but I used permatex at either the tranny to adapter or adapter to Dana 300 . I have a feeling it was the later and the reason for the leak.

My D300 leaks some but is always full of oil when I check so I think I also have a bad seal at the adapter and oil is flowing from the tranny into the D300.

 

[yellow85cj]

There are 2 seals on the input shaft at the point between the 300 and the T177. On is in the adapter and the other is in the 300. If you are going to do one, might as well do the other.

Here is the adapter side seal. Note it is the size of the 300 input shaft and does not touch the T177 output shaft.

Here is the seal for the 300. Not a good pic but you should be able to see the seal on the right.

Here is where the adapter and the T177 case need to be sealed. If you don't use the gasket, at the very least, you need to use some Super 300 or something similar to seal the two (where the red line is).

Can't recall if I used a sealer between the adapter and the 300. Seems like there should be so that the weep hole will function. When the seals go bad there will be no leak where the 300 and the adapter mate, but it will leak through the weep hole.Hope that makes sense.

 

[Neuner]

Excellent! Thank you.

Going to save this as a guide. I know I don't have all of the proper seals/gaskets in place.

 

[Neuner]

Finally got some time to drop the Dana 300 and see what was going on. I left the tranny in place. Replaced the seal at the adapter and installed a gasket between the adapter and tranny that wasn't there before.


Thanks again for the pics, they were a good reference. Hopefully this takes care of most of the leak.