There is a filter in the T-case, but it requires the T-case to be removed and taken apart. It is one of those life of the unit filters. I've seen people with 120+K on a t-case atf and not have it go bad. I change mine becuase it is a water vacume. and ATF is so cheap that it just makes you feel good to change it.

Some fluid is trapped in the pumpkins passage ways, and some fluid does go to the axle tubes. I don't recommend it, but you can run an axle like ours on 2 pints.