Haldex

[Nev Bertwistle]

I'll start by suggesting you read the Haldex Explained article in the Technical Documents section first so you have a basic understanding of how it works. In simple terms it's a viscous coupling at the rear of the propshaft (before the differential gear) which applies drive to the rear wheels based on maps contained within the Haldex module.

The Swedish patent was acquired by the Haldex Group in the mid 1990's and the first generation was released in 1998. There are Gen II, III, IV and V and the Haldex group itself was acquired by Borg Warner in 2010. They have been used in hundreds of models across many manufacturers but for our purposes we only need to consider those used by Volvo & Ford.

The Haldex unit is bolted to the differential housing but is its own separate unit. Most of the S40/V50 rear diffs/Haldex that you will see in Oz are a mixture of Gen II & III while the one found in the TE Kuga is a Gen IV. The main difference is in the oil pump and the programming in the Haldex module. The Gen IV has a revised pump to provide a small amount of residual pressure to the clutch plates to speed up responsiveness to requests from the Haldex module to provide drive to the rear. The programming takes greater emphasis to throttle position so will initiate lock (drive) to the rear even before it detects wheelspin.

Gen IV Haldex unit from a TE Kuga


The only thing you need to be across here is that you need a Ford Haldex module to talk to the Ford CANBUS network. Since your only option is a TE Kuga one, that's the one you need. Most wreckers will only sell the complete diff so ultimately you end up with the correct Haldex and rear diff in one. Just for reference you can unbolt a Gen II/III Haldex unit fron the Volvo diff housing and bolt on a Kuga Gen IV one but getting a wrecker to split the diff will be difficult. But it can be done.