perhaps this will explain the haldex system

http://www.haldex-xwd.com/

in snow i've noticed a slight delay in the rear wheels starting to drive when the fronts are slipping but never had the sort of scenario shown in the youtube clip.

i'm in the 2 wheel drive camp on that one

Rear wheels were dead all the time until the end. That spinning of the left wheel you saw is probably caused by car moving.

+ 1

Also; have a look at the wheel arch gap at the rear; significantly less than the front. I wonder what he had in the boot?

perhaps this will explain the haldex system

http://www.haldex-xwd.com/

in snow i've noticed a slight delay in the rear wheels starting to drive when the fronts are slipping but never had the sort of scenario shown in the youtube clip.

i'm in the 2 wheel drive camp on that one

Thanks; picture paints a thousand words! Always wondered how really it worked.

Edited 17 January, 201115 yr by bahnstormer vrs

I didn't realise there was a City & Guilds in Off Road driving...

Where can you study/take that?

Mike

I'm doing it through 4x4 Response Wales by spending probably one day out with an instructor, and then the next day doing the Assesment. It is almost totally practical course with a very short classrom sesion. Mainly covers:

Understanding how your vehicle works and being able to explain it.

Reading route capability for your vehicle.

Hill climb.

Failed hill climb.

Downhill control.

Side slopes.

Fording.

All done on an observed drive around an off-road site.

Because it is being done through our own Charity it should only cost me about £60, and we are doing them so our clients can be assured all our Responders come up to a fixed, known officially recognised standard. I can become an Instructor after due to other qualifications I have.

Externally several off-road centres offer a similar course, but it is likely to cost at least double what I will pay. Gogle BORDA or LANTRA.

It looks like I have already got a training session to give, as Ceredigion Health Care Trust have given their Critical Care Team a 4x4 Yeti but with no introduction to it or it's capabilities.

The Haldex coupling used in the Yeti is a Haldex IV coupling which transfers power into an OPEN rear differential. If the electronics isn't doing it's job with applying the brake on the spinning wheel (the left rear wheel in this video clip) it will spin the wheel with least traction..

The right rear wheel sits high in the wheel arch because the left rear wheel has spun a big hole. This causes the right wheels suspension to take "all" the load from the rear of the car.

The Yeti does not use XWD.

I'm doing it through 4x4 Response Wales by spending probably one day out with an instructor, and then the next day doing the Assesment. It is almost totally practical course with a very short classrom sesion.

Llanigraham - that sounds very interesting - worthy of separate thread and updates if you have the time! Will be interesting to see how the Yeti fares in that course and whether you think the course useful for us Joe Blogg drivers!

Cheers

Edited 18 January, 201115 yr by Totally Square

The Yeti does not use XWD.

As far as I knew it XWD was it the fancy name given by Haldex to their 4th Generation System which the Yeti does use? I might be wrong though?

The operation of the Yetis Haldex System does match what is being described on the link above as it does split and adjust the torque automatically and is always sending power to the rear axle albeit only a very small amount during travel on high traction surfaces?

Anyone know for certain if XWD is the same as 4th Gen Haldex?

As far as I knew it XWD was it the fancy name given by Haldex to their 4th Generation System which the Yeti does use? I might be wrong though?

The operation of the Yetis Haldex System does match what is being described on the link above as it does split and adjust the torque automatically and is always sending power to the rear axle albeit only a very small amount during travel on high traction surfaces?

Anyone know for certain if XWD is the same as 4th Gen Haldex?

Hi James,

Gen IV arrived in 2007 whereas XWD appeared in 2008, although if I read correctly the two can be combind to form one system. Next year should see the release of the Gen V system. Apologies have no infomation on the features Gen V.

See My link

Regards,

TP

Edited 18 January, 201115 yr by The Plumber