Hi someone can help me. I am looking for information about all four-wheel systems of the VW Audi Group. Starting from the mechanical urquattro via the torsendiffernzial to the haldex coupling in 4 motion. But, is there Haldex coupling also available at audio or is only the torsendifferntial installed here? because I read that the haldex coupling is better for ABS and ESP, because it can be electronically controlled. why does audi only build the torsendifferntial a ? why is the T4 bus with all-wheel syncro and not 4motion ? it may be that at VW there was also a non-permanent all-wheel system in t3 for example. For more information about all four-wheel systems and where they would be installed I would be very grateful Mfg Fireburner