Hi All, just wondering if someone could clear something up for good, I recently read a pretty old thread asking the question of can FL2 with their Haldex setup suffer from transmission wind up and it caught my attention because occasionally I like to drive short distances with Sand Mode selected which I found out from a much earlier posting gives the FL2 permanent 4WD, just to give the Haldex pump a bit of a working because my last Haldex pump seized, now I was so it seems wrong in thinking that 4WD vehicles with a transfer box can’t get wind up because I thought gearing inside that box allowed the 2 shafts to drive at different speeds and counteract the wind up, but someone pointed out in the old thread that Land Rover never designed the terrain response system to be used on grippy tarmac and so no system was built in to release any wind up when using the vehicle on tarmac and thus tight cornering etc causing this effect and subsequently they say you will eventually cause major strain and damage inside the transfer box, there eventually was no conclusion to the thread and everybody disagreed, does anyone know the definitive answer, is every now and then driving a short distance in Sand Mode going to lock everything up and explode my transfer box, thanks guys

I would say if the transfer box was to suffer failure as a result of what you are doing they must be soft as the brown stuff and not fit for purpose, think about it - whats its job, to pull and push the car out of trouble. if you are in a ditch with little traction, all torque could easily be delivered to 1 wheel to potentially pull or push twice the weight of the car.
With my current A6 quattro there is a certain amount of wind up in normal driving, if i take a sharp turn you can feel the tires scuff /jump.
I once exercised the diff locks on my ur quattro and then found myself in a concrete yard having to do a 3 point turn - lets just say i was concerned about windows getting smashed with flying stones. if you get proper wind up you will know about it.

I totally get what you’re saying and I’m thinking surely Land Rover who would of piled a huge amount of development in to the terrain response system wouldn’t develop a fail safe system to not allow for a certain amount of wind up, whether that be a warning light or some sort of gearing in the transfer box, you could have a situation where you’re driving in sand all day and then hit the tarmac but forget to engage standard road mode, what you get a few miles up the road and your diffs lock up, surely not

The TR system is designed to be fully automatic in normal mode, but surface specific in selected modes. The owners handbook is quite clear about using the correct settings for the surface that's being driven. If the surface isn't loose, then the automatic mode should be used. You will get damaging windup if other modes are used on grippy tarmac.

The PTU splines are the 1st failure point, as they're simply not designed to take axle windup leads.

So really that is the definitive answer, it is a bit of a shame you can’t select 4WD as and when you want but that’s why Haldex was invented I guess to take away that driver input, I’ll definitely stop selecting sand for a little burst then

sharmanator43 said:

So really that is the definitive answer, it is a bit of a shame you can’t select 4WD as and when you want but that’s why Haldex was invented

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The Freelander 2 and the FL1 before it aren't 4X4 vehicles in the traditional sense, with selectable 2X4 or 4X4 or locking transmission.
They are AWD which is similar to 4X4 in function to the centre diff lock, but generally AWD isn't as robust a system as a traditional 4X4.

You actully shouldn't drive a traditional 4X4 on the road, unless the tyres can slip, as the forces of axle windup are enormous, and in this respect the FL2 is no different.

In normal mode, the TR module is doing all the thinking for you, so there's no need for driver intervention at all.

The special programs are there so you can tell the system that you are on loose or slippery surfaces, as it can't know that itself. This is why the special programs should only be used when the tyres can slip.

sharmanator43 said:

I guess to take away that driver input

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sharmanator43 said:

I’ll definitely stop selecting sand for a little burst then

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The system does actully apply AWD when you accelerate, to eliminate wheel spin, so there's no need select anything else. The only time AWD isn't applied, is when the steering position sensor is reading a moderate steering angle, which is done to limit damaging axle windup.

That’s all really useful information, I’m glad I asked now, so the Haldex pump does get use under pulling away acceleration it’s not just idle under normal conditions, I never knew that, that’s really helpful thanks for that, I just hope I haven’t already put undue strain on the splines enough to cause a weak point, I have literally on done it 2 or 3 times on a fairly straight road and at low speeds

sharmanator43 said:

so the Haldex pump does get use under pulling away acceleration it’s not just idle under normal conditions

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Yes. When you accelerate, the TR system automatically applies power to the rear diff via the Haldex, so the pump must activate.

sharmanator43 said:

I haven’t already put undue strain on the splines enough to cause a weak point, I have literally on done it 2 or 3 times on a fairly straight road and at low speeds

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It's best not to force the TR to engage AWD when it's not needed, as it can cause damage, although this should be minimal if the tyres are identical, and the road is straight.

It's sensible to replace all the fluids every couple of years, rather than leaving it until the 10 year change interval.