The K46 does have serviceable seals and axle bushings, I believe the seal is driven in rather than being retained by a lip in the housing. You should be able to tell by cleaning the area up and having a look. If it is an active leak rather than a light seep, it should be attended to sooner rather than later. If not sure, clean it up and watch it. No leaks are obviously better than having one. Plus, you get the opportunity to change the oil.

I have the same leaking right rear seal with a K46 tranny...

Can the seal be replaced without removing the axle?

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