Function

The Haldex-clutch enables for all wheel driven vehicles an electronical control. This is not always the case with the (only mechanically operating) Torsen differential. This makes it combinable with an antilock braking system.

How it works

Differences in speed between front and rear axle make a (green) swash plate turn and the two (or more) inside pistons pump oil to the outside ones. These make a multi-disk clutch connect the (blue-green) housing and right shaft with the grey left one. The mechanism only needs half a rotation to produce enough oil pressure for the clutch. The pipe between pump and clutch contains a throttle valve. It can be controlled electronically if the ABS-system is working or the slip has to be varied.