Haldex is an intelligent 4WD system that was developed in Sweden in the 90s. It is used in all of the VAG Group transverse engine mounted vehicles since 1998.
It consists of an electronically controlled multi plate clutch pack, which can regulate torque to the rear differential in a vehicle, and govern the bias of front / rear drive – making a primarily FWD car in to 4WD instantly. This is the system that we can disable when putting these cars on to our 2WD Dyno.
The Haldex coupling has its own oil supply, a pre charge pump and clutch pack and like any system requires regular oil changes. The service interval for any Haldex Coupling is 20k miles.
The Haldex system has always been constantly developed and improved over its lifetime in to generations as noted below.
Gen 1 – Found in Mk1 Audi TT, 8L A3/S3, Golf 4/Bora/Leon/Octavia 4Motion
Gen 2 – Found in Mk2 Audi TT, PFL 8P A3/S3, Golf 5/Jetta 4Motion
Gen 4 – Found in Mk2 Audi TT (late), FL 8P A3/S3, Golf 6 etc
Gen 5 – Found in MQB cars such as Golf 7, 8V A3/S3, TT etc
The various generations require different oil and filters, although we can supply and service all of the models. We only use genuine service items for these couplings.
An often overlooked part of the rear diff assembly is the differential itself, and that is because the VAG group list it as a lifetime sealed unit. We know now that this can cause issues with bearings and seals so we advise that the rear differential is serviced with high quality gear oil. We can carry out this service at the same time as a Haldex service and also update all records, even on line.
If you are unsure about the Haldex version in your car or the service interval then get in touch and we can advise you.
