Changed CVT fluid and both filters. I used 3.75 quarts of CVT fluid, but maybe 3.5 would have been enough. FSM says 3.0, but that doesn't include replacing the internal filter. The fluid coming out was close to black, I hope it wasn't too far past its intended service life.
Also replaced the gasket seen in the photo. Carb cleaner plus a rag, all you need, but it takes a while. I think I spent about an hour and a half working on that.