In een bespreking van de 2003 Legacy
http://www.123review.com/reviews/subaru/03_subaru_legacy_outback_driv_imp.html

Actually, Subaru builds three different all-wheel-drive systems.
Manual-transmission models rely on a viscous coupling, a kind of
speed-sensitive automatic clutch, to limit wheel slip at either end of
the car. The system is purely mechanical, and nominally distributes
driving torque 50/50, front/rear. Active All-Wheel Drive, standard
with automatic transmissions, replaces the viscous coupling with an
electronically managed multi-disc clutch. Torque distribution remains
50/50, but Subaru claims this system can respond more quickly to
changing conditions. The Legacy GT automatic and all VDC models come
with Variable Torque Distribution, which combines the electronically
managed center clutch with a planetary gear that splits torque 45/55
front/rear, for a sportier feel. VDC models combine Variable Torque
Distribution with electronic traction control. Additional electronic
sensors monitor the position of the throttle and steering wheel, as
well as the vehicle's yaw rate and the individual speed of each wheel.
The traction-control function can be turned off with a switch, a
feature that may be useful in deep snow or mud.


en

http://pub110.ezboard.com/fultimatesubarumessageboardsfrm6.showMessage?topicID=93.topic
Automatic transmission: It uses an extension housing on the end of the
normal FWD auto transmission. The rear housing has a separate clutch
pack, and a line that feeds pressurized tranny fluid to the clutch
packs. There is a solenoid there to control how much pressure is
applied to the clutch packs, essentially controlling the torque split
fore & aft.

On the older transmissions the torque split is 90% front, 10% rear.
The most it can transfer in one direction or another is 50/50.

The newer autos have VTD (variable torque distribution) and act more
like a true AWD setup. They normally have 45% front, 55% rear. Again,
I believe max torque split f/r is 50/50.