okay, stay with me on this one....

there is a source of silicone oil that is:
-compatible with rubber seals
-very high temp tolerance
-readily available and inexpensive

ready for this?  drum roll please <budda budda budda>

Silicone Brake Fluid.

huh?  ya think?  maybe this is an industry secret, the great Parts
Conspiracy.  sell customers a $3000 fluid coupling when all it needs it a
change of $20 worth of silicone brake fluid.  whose willing to try on their
trashed unit?

better yet, someone give me their Syncro and i'll try it.

-dan