Driveshaft flange seal will not budge, has it melted and seized itself In?

[Paperclips43]

First I’d like to express my extreme gratitude for everyone on this forum. The amount of knowledge and experience here is 100% the reason I was able to keep my car on the road.
Because if you guys I was able to compete the following projects
Crankcase breather hose system replaced.
ATF fluid and filter change.
Rear and front differential fluid change.
Cv axle.
Replaced my air hoses and spark plugs and re gapped them.
I solved the hard start issue because of this forum. Now when it starts it fires up in a second.
I checked compression on a cold and warm engine all was good.
When ever a seized bolt halted my progress I never gave up. Just kept at it kept researching and knew I would figure it out.

However this is really got me stumped and I don’t know what else to do I’m but determined to find a solution.

I’ve read and read and read everyone’s write ups on this job and I just can’t seem to find someone with the same issue.
This rear driveshaft flange seal seems glued or welded in there or melted.

I’ve read a lot of people having trouble getting the driveshaft out but mine came out with two soft thumps of a rubber mallet. Easy peasy it’s been up to this point and i don’t find anyone else having the seal be the hardest part.

We’ve tried prying with flat heads, picks, pry bars, lathe tools. We’ve tried cutting it out with wire cutters and

One thing that seems odd in this case is there is what looks like Teflon tape around the seal. I don’t think it is Teflon tape but you can see the white strips in the pictures. But maybe some kind of adhesive or I really don’t know. I do know that it has not budged with all the force we’ve put on it nothing. And I’ve dealt with my fair share of seized bolts so I understand stuck things needing a push.

So if anyone can help I would appreciate it. I’m sure any idea will be better than dremeling it out of there or melting it out with a torch.

[Paperclips43]

https://albums.memento.com/top27726

[Paperclips43]

Not sure if my link works to post pictures I’ll try to find a different way. Also thought I should add my car is a

99 Audi a6 c5 automatic 2.8l Quattro wagon.

[Linco]

Looks like someone has used silicone or some kind of RTV sealant on it.

Did you get it out without damaging the housing?

[Paperclips43]

I did yes. I ended up taking out the housing. It’s only like 4 bolts and the seal was stuck in there so bad I was hammering with a socket under a piece of wood for a good 20 minutes. And spraying good off and using a pick to pry It apart so the solvent could penetrate. I wasn’t hammering full force because I didn’t want to damage the housing but again a solid 15-20 minutes I got it free!

Having the housing off made it so much easier I wonder why more people don’t do it this way unless normally the seal just comes right out. It felt good to be able to clean everything a little better and easily set the seal in there. 50 miles later no leak!

Now I’m not driving it anymore until I do TB because I have no idea when it was done and I can’t have peace of mind until it’s all good in there especially now that I’ve done so much work to the car.

Boy does it drive so much nicer with that center differential fluid and seal work. Also did the other two diffs and transmission fluid it’s a really nice car it definitely feels worth her asking me for money all the time.