It snowed last night and was about 2" deep by morning. Had to go into town (Newtown is 26 miles away) for shopping and fuel. Good time to check out my winter tyres and 4x4. First the good bits - The heated winscreen cleared the ice and snow in less than 5 minutes! The heated seat a little longer. It's down hill for the first 2 miles, again no problem (note: we don't get any gritters up in the hills!). It is flat for a mile, then a steep winding hill. I could see the first casualty, a car with hazard warning lights on stuck in the middle of the road, wheels spinning. It was my daughter trying to get to work in her Peugeot 107 (summer tyres & no Traction control!). She is an experienced driver; but could not get any grip. With a lot of back & forth we managed to get it into a farmers drive, where we abandoned it! No trouble getting to Llanidloes. I did not get any wheel spin and fairly sure the 4x4 drive did not come into play (?) Does anyone know, how you know if the Haldex clutch comes into play. If the traction control light flashes (which it did not) and in most cars you can feel that when it is working. Can you feel the 4x4 on the Yeti?

My winter tyres are 205/60 R16" Goodyear Eagle Ultra Grip GW-3.

My daughter is having Yokohama winter tyres fitted tomorrow...

Peter

Evening Peter.

I guessed you must have had a few flakes up there, but if you will live up that high in the rarified atmosphere, what do you expect!!

No you can't tell when the Haldex works; it is that subtle, but it won't actually come in until it senses about a quarter of a turn "slip" in a front wheel. I got up the short rise to the bungalow when I arrived home this morning at 0700, but someone else hadn't. Sheila hadn't warned me and the snow didn't really start until after Newtown. Nothing here in Ludlow!

Whose fitting the Yoko's?

Evening Peter.

I guessed you must have had a few flakes up there, but if you will live up that high in the rarified atmosphere, what do you expect!!

No you can't tell when the Haldex works; it is that subtle, but it won't actually come in until it senses about a quarter of a turn "slip" in a front wheel. I got up the short rise to the bungalow when I arrived home this morning at 0700, but someone else hadn't. Sheila hadn't warned me and the snow didn't really start until after Newtown. Nothing here in Ludlow!

Whose fitting the Yoko's?

Morning Graham,

Andrew, from Smart Tyres - and they are not that cheeeep! Fast fit Seven in Newtown are quoting £58 for continentals (not sure which winter tyre) and Smart Tyres £70 'ish for the Yokohamas'...

Aren't these gen 4 Haldex's always pushing a little bit? In the freelander (first application of gen 4 IIRC) the haldex is locked in every time you start from stop.

But even in my work car which has a viscous rear 4wd system, you can't feel anything. The slip just increases on the front and the rear just slowly starts pushing. I'll let you know how my Gen 2 haldex scout goes in the snow hopefully in 6 months.

In the Seat Leon 20VT4 that I used to own (with an earlier generation Haldex) the shift of power from the front wheels to the rear ones was noticeable in certain very slippery circumstances. Particularly in the wet on slippery tarmac when the shift occurred suddenly, I could feel what can best be described as a "thud" when the Haldex clutch shifted power to the rear wheels. Does this not occur with the new generation Haldex?

I'll get the chance to also try it out in the Yeti, as I should be taking delivery of my new 1.8TSi 4x4 today or tomorrow!

In the Seat Leon 20VT4 that I used to own (with an earlier generation Haldex) the shift of power from the front wheels to the rear ones was noticeable in certain very slippery circumstances. Particularly in the wet on slippery tarmac when the shift occurred suddenly, I could feel what can best be described as a "thud" when the Haldex clutch shifted power to the rear wheels. Does this not occur with the new generation Haldex?

No.

It's far better.

No you can't tell when the Haldex works; it is that subtle, but it won't actually come in until it senses about a quarter of a turn "slip" in a front wheel.

That's a description of how generation 2 haldex works. The Yeti's gen 4 system is pre emptive and doesnt work like that. It's always sending drive to the rear and doesn't require the front wheels to slip to activate.

In the Seat Leon 20VT4 that I used to own (with an earlier generation Haldex) the shift of power from the front wheels to the rear ones was noticeable in certain very slippery circumstances. Particularly in the wet on slippery tarmac when the shift occurred suddenly, I could feel what can best be described as a "thud" when the Haldex clutch shifted power to the rear wheels. Does this not occur with the new generation Haldex?

I'll get the chance to also try it out in the Yeti, as I should be taking delivery of my new 1.8TSi 4x4 today or tomorrow!

That's exactly how my previous Octavia mk1 4x4 turbo felt and worked. That generation 2 system s worlds apart from the generation 4 setup in terms of downsides and quirks. :-)

I like the clunk of the haldex engaging in my Octy. It is its own little way of confirming its existence to me and saying 'yep, you really did buy a 4x4 one!'.

If your wheels span at all, then you can be sure the haldex was operating.

That's a description of how generation 2 haldex works. The Yeti's gen 4 system is pre emptive and doesnt work like that. It's always sending drive to the rear and doesn't require the front wheels to slip to activate.

Well my Yeti must be fitted with H2 then!

Sorry but there has to be some slippage sensed before the system "locks up"

Having watched my missus leaving for work this morning, with about an inch of snow outside, I noticed that the front wheel I was looking at did slip but only by a tiny amount (literally only 3" of tread) before the car moved forward with no slip at all.

Thumbs up for haldex and winter tyres

Well my Yeti must be fitted with H2 then!

Sorry but there has to be some slippage sensed before the system "locks up"

It doesn't 'lock up' does it? It simply increases the amount of torque to the rear axel from the 5-10% it runs all the time. Hence it's always being driven. I had someone video my yeti in snow across our empty car park at work when I first got it. On my previous gen 2 car you could feel the transition of torque, feel the fronts momentarily spin up and even hear them chirp in the dry. My Yeti doesn't do any of that from the feel of it or what we saw on the video. :-)

Having watched my missus leaving for work this morning, with about an inch of snow outside, I noticed that the front wheel I was looking at did slip but only by a tiny amount (literally only 3" of tread) before the car moved forward with no slip at all.

Thumbs up for haldex and winter tyres

Have to totally agree. I'd never dream it could put down 300bhp/300lb/ft torque down so cleanly in such extreme conditions but it does! It's so sure footed, I struggle to see what real life benefits Quattro could offer.

It doesn't 'lock up' does it? It simply increases the amount of torque to the rear axel from the 5-10% it runs all the time. Hence it's always being driven. I had someone video my yeti in snow across our empty car park at work when I first got it. On my previous gen 2 car you could feel the transition of torque, feel the fronts momentarily spin up and even hear them chirp in the dry. My Yeti doesn't do any of that from the feel of it or what we saw on the video. :-)

I know exactly how the Haldex system works thank you.

"Lock-up" in quotes was figurative.

And as CFB says the front wheels do slip, but only a little. I have experienced this plenty of time both in snow and mud.

The real benefit of a full-time-4wd system (quattro etc) is 50/50 (or thereabouts) drive all the time. The gen 4's are very good and have made up most of the difference, but there is still a benefit in sharing the traction (and drive forces) as equally as possible, rather than mostly front and then shuffling it around.

I know exactly how the Haldex system works thank you.

"Lock-up" in quotes was figurative.

And as CFB says the front wheels do slip, but only a little. I have experienced this plenty of time both in snow and mud.

Here you go again. I was asking, hence the question marks! Another pathetic out of context response from you. Some people are interested in learning from others experiences. Some just think they are always right. I'll not waste my time any further, reading or replying to this thread now as it will inevitably now go down hill in the usual flames. Enjoy ourself in the knowledge that you are always 100% correct, in your own eyes anyhow.

Oh what the hell!

Peter,

We noted they were working on the blower plough this afternoon, probably checking it over, so it looks like they are expecting the 10" that "Wet Derek" mentioned on the BBC News lunchtime.

(Mind you I'm not sure than 10" and Derek Brockway quite go together in polite society!!)

I thought this might stir up some controversy! I love the word "Pre-emptive" - it sort of means a magic box that thinks quicker than you or the mechanics.

This is a quote from Wikipedia :http://en.wikipedia.org/wiki/Haldex_Traction well worth reading

"The LSD used by Haldex 4.0 is also not the mechanical limited-slip differential of old. They swapped the old system LSD for an electronic unit. The eLSD works in much the same way as the LSC, a feeder pump and pressure relief valve are used to control hydraulic pressure on the differential clutch pack. This allows for complete control of the rear differential lock-up without the need to wait for wheel slippage to occur. The system has its own control unit contained in the LSC. This control unit communicates between the vehicle systems to get sensor input for data such as wheel speed, rpms, throttle position, steering wheel input, etc. It also works with anti-lock brake and traction control systems.

The XWD system can transmit 100 percent of available torque to either the front or rear wheels".

It also states that the "Fifth generation - due 2012". Apparantly it tells you how to drive in the snow; that you are driving too fast and you are going to be late! - They are going to call it a Haldex V5-SWMBO driving aid.

It's snowing now; but expecting a lot more tomorrow. (I have to lean out the bedroom window with a feather duster on a long pole to sweep the snow from our satellite dish, otherwise my "slowband" stops altogether!!

Graham, Lucy, on the ITV weather, is much prettier than Derek...

Peter

PS My Emotions, fonts etc, are greyed out when writing a reply... Anyone know how to restore them?

.....PS My Emotions, fonts etc, are greyed out when writing a reply... Anyone know how to restore them?

Annoying. I usually stay signed in but when this happened to me last autumn, a 'sign out/sign in' cured it. Good luck... :peek:

As I'm sure people on here know, it doesn't only wait for wheel slip to send more power to the rear. I'll avoid the term "lock up".

There are several other situations where it sends more power rearwards and needs no wheel slip at all before it does so.

To get up the slope to our bungalow this morning I definately felt the front wheels spin slightly before I got proper traction, so it certainly does happen. That was accelerating from almost a standstill on snow over ice, here:

http://goo.gl/maps/fr5vE

I think I have always sensed some slippage before I have got the rears to drive. Perhaps I'm wrong, who knows.

Peter, I note the blower has gone out!!

And Behnaz is best!!

To get up the slope to our bungalow this morning I definately felt the front wheels spin slightly before I got proper traction, so it certainly does happen. That was accelerating from almost a standstill on snow over ice, here:

http://goo.gl/maps/fr5vE

A bit different from the old place Graham. Does this mean you have a view now?

Edited 17 January, 201313 yr by speedsport

Very different!!

Front:

http://maps.google.co.uk/maps?q=Well+Lane,+Llanidloes&hl=en&ll=52.449095,-3.534651&spn=0.003708,0.006899&sll=52.449092,-3.537732&sspn=0.001867,0.003449&oq=Well+Lane&hnear=Well+Ln,+Llanidloes,+Powys+SY18,+United+Kingdom&t=m&z=17&layer=c&cbll=52.449095,-3.534651&panoid=NaXAXbsETxuYKHyVwBSPhA&cbp=12,321.81,,0,0

Back:

Just returned from a run up to the Mountain Centre at Libanus in the Brecon Beacons for lunch. No problems with the roads/ engine warm-up etc, so a nice drive.

Just north of the summit at the Storey Arms there was a nice big snow covered layby, which was originally the old road.

Time for some experiments - slight downhill braking on 17" "summer" tyres was dreadful, the abs was chittering away but had little effect on actual braking as there was no grip. Uphill traction was quiet good, although with a lot of clattering, progress was made fairly easily.

Lesson learned - downhill to be avoided at all costs, uphill ok if there is an escape route on these tyres

On my old Suzuki SJ 413 with rigid 4 wheel drive transmission, locking rear diff and four wheel disc brakes, old Colway MT tyres it would not have been a problem at all. Individual wheel locking is so much harder with a rigid system, keep the wheels rolling and good braking is easily obtained.

Suzuki wins hands down.

Moral is when the existing tyres wear out, some all weather tyres are going on.

Edited 17 January, 201313 yr by Yety

To get up the slope to our bungalow this morning I definately felt the front wheels spin slightly before I got proper traction, so it certainly does happen. That was accelerating from almost a standstill on snow over ice, here:

http://goo.gl/maps/fr5vE

I think I have always sensed some slippage before I have got the rears to drive. Perhaps I'm wrong, who knows.

Peter, I note the blower has gone out!!

And Behnaz is best!!

No comment from bob, is he asleep in front of his wood burner? or had one or two :beer: in the corner and nodded off ?.

She could keep me warm.

I'm going, hope Bobs left a pint or two

Get in the queue, Kevin!!