Jeff,
For what its worth, I'm not sure its Hytran. Its hard to describe, but Hytran has a peculiar "stink" to it (sorry, "odor"). Once the cover is off, I've found so many "globules" stuck to any surface available that it would be hard to deny it is Hytran.
For others, the previous owner of my 782 tells me he has switched to "regular hydraulic fluid" with no (perceived) ill-effect. Thoughts, anyone?
Again, for Jeff, since I've changed Hytran only one more time than you, I wouldn't count my word as authoritative. But I've read others recommend annual fluid changes because of the water retainage.