Is this an automatic or a manual transmission(I'm guessing automatic)? Please list the part numbers you are using.

 

automatic 4T45E tranny.

 

Did you use this seal kit from AC Delco?

https://www.rockauto.com/en/catalog/...haft+seal,2336


I used 2 of these Cardone cv axles from RockAuto, the fit right into place and didn’t cause any problems with the stubshaft or coupler.
the seals fit perfectly.

 

There is a foreign object in there. I don't see anything it could be on the exploded view that I posted. There is not supposed to be an inner seal, just the outside.
That's why I posted the exploded view.

 

Don. Pretty sure the foreign object you mention is the pin in the ring and pinion (or whatever the correct name is)

 

Maybe this will help

 

Anyo

Does this sleeve look like it’s in the correct place? This is what the stub shaft sleeve is hitting and making it not go in any further.

 

My guess is that is the old bushing.

 

Any chance that the old bushing is still inside the transmission and the new shaft came with a new bushing and you're trying to install 2 bushings where there should only be 1 ? The extra bushing would be riding right where the seal is and could be the cause of the damage.
I'm not implying this is sure thing, but we've all had our own "Duh" moments when working on cars.

 

Here is another video of the mysterious “sleeve.” it’s forsure not the old seal.