23
Transmission
Advantages
●
Coupling control not dependent on driving
situation
●
Fast moment build-up by means of pre-control
●
Permanent rear-axle drive capacity
●
Fully compatible with the traction control systems
(e.g. ESP, ABS)
Four-wheel drive coupling generation IV
In principle, power is transmitted via the clutch plate set on the fourth generation of the four-wheel drive coupling
in the same way as the previous Haldex models. The pressure being built up with an electric pump is a new feature.
The four-wheel drive control unit J492 determines the torque to be transferred by controlling the coupling opening
control valve N373. Speed differences between the front and rear axle are no longer required to activate the four-
wheel drive coupling.
Technical features
●
Electrohydraulically controlled plate clutch
●
Integrated in the rear axle drive
●
Simplified hydraulic system
●
Optimised, demand-regulated pump control
S404_043
You will find information on this topic in self-study programme 414 “4Motion with Four-wheel Drive
Coupling Generation IV”.
