I fully support advice to flush tranny. I use Amsoil but Mobil 1 Synthetic is fine too.
For the power steering, Volvo uses (initial fill), and sells, a special synthetic fluid which is greenish in color. If you're in doubt, hang a small magnet in the fluid reservoir, and see how much steel dust it pulls out. I hung a magnet with a hole from the cap spring for a week using nylon cord. Installed filter/magnet combo (from IPD) in the return line to the reservior after doing this test.