Audi will use the same 4WD system in the new A3.

[The Pretender]

http://static.autoblog.nl/images/wp2012/big/mercedes-4matic-a-klasse.jpg

[The Pretender]

http://blog.mercedes-benz-passion.com/wp-content/uploads/2048_12C1270_07.jpg

[Joker]

Can Audi use this very same system in the A3 because this one was co-developed by Haldex and Mercedes.

[The Pretender]

According to info the new MQB Haldex developed especially vor VAG MQB platform has the same technical layout with the new central diff.
If VAG not use the new (Haldex 5) layout (Central diff connection and disconnection at the front) and will go on with the old Haldex 4 (Right drive shaft connection and disconnection at the rear) VAG will have a inferior system to Mercedes.
The new A-Class Merc will win every test between it and the new A3, Golf and so on, because the new central front diff and new rear diff are much better in transferring power to the wheels.

[andreadebi]

in the latest issue of italian magazine "Quattroruote" there is the comparison test a3 sportback 2.0 tdi 150 hp vs a3 sportback 2.0 tdi quattro 184hp s-tronic (available from end of summer 2013)
About the 4wd quattroruote wrote:
About the awd system,there is new and lighter graft with multiplate clutches in an oil bath (actionated by an eletric pump with a maximum pressure of 100 bar) which in few milliseconds may also sends the torque to the rear
power distribution between front and rear is controlled by an electronic control unit

That's all, still unclear if it completely new as mercedes system or only a revised one

[The Pretender]

If it's revived one, it will be still Haldex 4.