Might seem an odd question but while I was up in the Lake District over the New Year in my Scout I twice tried to reverse up onto snow covered grass & the front wheels were spinning & the rear wheels appeared to do nothing. I've never had this problem while in forward gears.

Regards

David

I do not specifically know but I should imagine that it does. It uses electro hydraulic operated pressure plates and not a viscous coupling so it should work equally well in either direction but good question.

In theory it should work. The haldex uses a swash plate pump to generate pressure when theres a difference in speed between the input shaft of the diff and the rear prop shaft. The difference in speed produces hydraulic pressure which closes up the clutch.

The later gen 4 haldex system can also be controlled by ESP which can close the clutch up regardless of slip. If it has the ability to keep the clutch open too I don't know but I very much doubt it. quite often when stuck the best way out is backwards and would seem rather pointless to have a car like the scout that only has 4wd in one direction

I'll bet a fiver it should work in reverse :p

Thanks for your quick replies.

I also expected there to be no difference between forward or reverse gears so what explanation (if any) is there for the front wheels spinning with no apparent drive to the rear wheels? Worst case I would have expected both front & rear wheels slipping but my wife was out of the car & saw no movement from the rear wheels.

Regards

David

Thanks for your quick replies.

I also expected there to be no difference between forward or reverse gears so what explanation (if any) is there for the front wheels spinning with no apparent drive to the rear wheels? Worst case I would have expected both front & rear wheels slipping but my wife was out of the car & saw no movement from the rear wheels.

Regards

David

I am no expert on how the haldex system works but could the car have been cross axled with diagonally opposite wheels nearly off the ground and not able to grip? Were both front wheels definitely spinning, even if the rears were not?

Just a thought but I would be interested in the reason too, it is not something I have experienced in my 4x4 but I have never really paid attention to it .

Why does the 4x4 only work some of the time? Can you force it on? If not seems a bit annoying as sods law dictates it won't kick in when you really need it.

Edited 14 January, 201016 yr by luke_a

I am no expert on how the haldex system works but could the car have been cross axled with diagonally opposite wheels nearly off the ground and not able to grip? Were both front wheels definitely spinning, even if the rears were not?

Just a thought but I would be interested in the reason too, it is not something I have experienced in my 4x4 but I have never really paid attention to it .

All 4 wheels were firmly planted on the ground, I was reversing off an icy road onto a slightly raised piece of snow covered ground. Now that I think about it a bit more my original question is not correct because I remember that I also had great difficulty in driving forward out of this situation with my front wheels spinning and no drive from the rear wheels, I had to rock the car with gently throttle use to finally get moving. I was very disappointed in how the car performed.

I know that the Haldex clutch is working because on other occasions before and since I have felt the front wheels give a little slip then the rear wheels have gripped.

Regards

David

I am no expert on how the haldex system works but could the car have been cross axled with diagonally opposite wheels nearly off the ground and not able to grip? Were both front wheels definitely spinning, even if the rears were not?

Just a thought but I would be interested in the reason too, it is not something I have experienced in my 4x4 but I have never really paid attention to it .

Cross axle situation should not exsist with the Haldex 4 system.

Why does the 4x4 only work some of the time? Can you force it on? If not seems a bit annoying as sods law dictates it won't kick in when you really need it.

According to Haldex thei 4th generation system responds in less the 1/7th of a wheel rotation and within so many micro seconds. In practice this should ensure very rapid response.

Why does the 4x4 only work some of the time? Can you force it on? If not seems a bit annoying as sods law dictates it won't kick in when you really need it.

The design of the Haldex clutch is such that in all 'normal' conditions the car behaves like a front wheel drive vehicle; if the front wheels lose grip and slip a quarter of a turn then the clutch passes power to the rear wheels, how much power depends on how much the front wheels are slipping, I believe it can transfer up to 90% if required. This is a much more economical implementation as full time 4x4 will generally use up more fuel.

Regards

David

Not really adding anything useful, but I was speaking to my mum last night and she was saying her VW Tiguan was stuck as she couldn't reverse out of the drive yesterday.

She said in all the snow, the Tiguan had been fine around the country lanes but then wouldn't reverse out of the drive

I'm assuming it has the same Haldex system?

I'll be watching this thread with interest to see if anything else comes to light. Does seem daft not to work in reverse though :S

Photonut,

Ask the same question on the Yeti Forum see what they have to say. For the life of me, I can not see why it should be any different in reverse to going forward. If it was a viscous coupling then it might well act slightly differently but it is not. Unless the programming is set up to behave differently in reverse. Their could also be a fault in the system. If all wheels where spinning and car is not going anywhere then that would just be a lack of traction problem, I would not expect with a Haldex 4 system to have one some wheels stationary and others spinning and yet remain stationary. I have traction control in my Jaguar X 3.0 SP, all wheel drive and that behaves in an odd fashion but still gets grip on the other wheels. Turn off traction control and the revs shoot up and you remain stuck. The Jaguar system is not as good as Haldex 4th it does allow wheels to spin far more than I would like. Without seeing it is hard to be objective.

I must say, I am Rabbiting on about Haldex 4th, I just presume that is what your car has??? Or is it an earlier system?

Edited 15 January, 201016 yr by Anthony 1

I must say, I am Rabbiting on about Haldex 4th, I just presume that is what your car has??? Or is it an earlier system?

It is an 07 Scout so I guess that will be the Haldex 2.

Regards

David

Ah yes, sorry. the Haldex 2 is far slower in operation also it does not have the electronic limited slip rear differential as Haldex 4th gen cars will have. The Haldex Web site is very informative! belay that about asking on the Yeti site it is a different system. Also contrary to what I said above about not cross axleing, possibly it might well do without the e limited slip rear differential. So apologies to Forester also. The VW Tiguan does use Haldex 4th as far as I understand so that is interesting about it not reversing but I would need to see it happening to understand what is going on. Any way sorry i shall but out, good luck with a better understanding of how your system works. Winter Tyres will make a huge difference.

Ah yes, sorry. the Haldex 2 is far slower in operation also it does not have the electronic limited slip rear differential as Haldex 4th gen cars will have. The Haldex Web site is very informative! belay that about asking on the Yeti site it is a different system. Also contrary to what I said above about not cross axleing, possibly it might well do without the e limited slip rear differential. So apologies to Forester also. The VW Tiguan does use Haldex 4th as far as I understand so that is interesting about it not reversing but I would need to see it happening to understand what is going on. Any way sorry i shall but out, good luck with a better understanding of how your system works. Winter Tyres will make a huge difference.

Thanks for your help Anthony, I am looking at some winter tyres as per other threads on this forum, the types available for my 17" rims are a bit limited so I will have to play with tyre sizes on 16" steel rims, apparently the handbook gives options so I will have to take a look. I may be a bit late for this winter though because the wait for the better tyres seems to be quite long due to high demand (for some reason).

Regards

David

The winter has only just started, this snow was very early so their could potentially be plenty yet to come. In any case it is not just about snow as I am sure that your aware it is about being safe on ice and slush and also the winter tyres will clear water much better. Better braking and less chance of ending up in a ditch or worse. Winters have very soft compounds that remain soft even in subzero temperatures while ordinary tyres looze grip from between 7 C - 4 C down. Even then, buy now put them on over winter take them off in the spring and they will be with you next season. It is an expense but the summer tyres will be getting a rest while you use the winters.

I do not know why, I just assumed your car was new. You may find Winter Tyres becoming available again because the demand will have died down somewhat, I think that the prices had risen and they had become scarce.

Good luck and enjoy your winter motoring.

David,

I have an 07 4x4 TDi on 16" wheels with (so basically the same set up as your 07 Scout on Haldex 2) and can categorically confirm that the Haldex does work in reverse. I have a steep-ish drive that I reverse up and there is absolutely no doubt that when the fronts have started to slip in the bad weather both this year and last that the rears have come into play and dragged it up the drive. This I've both felt and seen (when the wife has been driving).

I would suspect that you need to get the car checked in some way - what's the mileage - is it sufficient to have the haldex fluid changed? or could one of the haldex clutch plates have had it?

Thanks for your help Anthony, I am looking at some winter tyres as per other threads on this forum, the types available for my 17" rims are a bit limited so I will have to play with tyre sizes on 16" steel rims, apparently the handbook gives options so I will have to take a look. I may be a bit late for this winter though because the wait for the better tyres seems to be quite long due to high demand (for some reason).

Regards

David

Hi

handbook only gives rim and tyre size but not rating or load index. Fortunately magic62 from Germany came up with a PDF list on rim and tyre combinations for all Skoda vehicles from Skoda Germany. Find your model and engine code (build sticker in the service book or boot floor) on the list and you will have the rim and tyre combinations and specifications that will fit.

My link

Regards,

TP

My mileage is only 27,000 so well below the time for a fluid change.

I've just been reading through the owners manual and with the EDL & TCS working in conjunction with the ABS all under the umbrella of ESP (just love all the abbreviations) I cannot understand how it is possible to have the wheels spinning in the way that mine were. The TCS/ESP light did come on when the wheels were spinning but didn't appear to have any effect, perhaps my car was built at 5 to 5 on a Friday and all they installed was the ESP button & the warning light & didn't bother with all the fancy bits.....

Regards

David

Hi

handbook only gives rim and tyre size but not rating or load index. Fortunately magic62 from Germany came up with a PDF list on rim and tyre combinations for all Skoda vehicles from Skoda Germany. Find your model and engine code (build sticker in the service book or boot floor) on the list and you will have the rim and tyre combinations and specifications that will fit.

My link

Regards,

TP

So if I'm reading the list correctly, apart from the wheel/tyre combination that you currently have fitted you could also have the same as I currently have - 225/50 R17 94W?

Are your steel wheels from Skoda or a third party? I assume that if I was to get a set of tyres/steel wheels from some of the suggested vendors on the web I would require a different set of wheel bolts to what I currently have fitted with my alloys?

Regards

David

My mileage is only 27,000 so well below the time for a fluid change.

I've just been reading through the owners manual and with the EDL & TCS working in conjunction with the ABS all under the umbrella of ESP (just love all the abbreviations) I cannot understand how it is possible to have the wheels spinning in the way that mine were. The TCS/ESP light did come on when the wheels were spinning but didn't appear to have any effect, perhaps my car was built at 5 to 5 on a Friday and all they installed was the ESP button & the warning light & didn't bother with all the fancy bits.....

Regards

David

Hi David. I have an 07 Scout, and yes the 4x4 definitely does work in reverse. I had to reverse out of a snow drift this week and and the rear wheels are the ones that got be out of it. Performance on snow has been superb for me (I have all season tyres on).

Hi i have a 57 scout tdi and in will spin the rear wheels in reverse it engages drive to the rear very quickly.

So if I'm reading the list correctly, apart from the wheel/tyre combination that you currently have fitted you could also have the same as I currently have - 225/50 R17 94W?

Are your steel wheels from Skoda or a third party? I assume that if I was to get a set of tyres/steel wheels from some of the suggested vendors on the web I would require a different set of wheel bolts to what I currently have fitted with my alloys?

Regards

David

Hi David,

Yes my Yeti as standard has 17" Dolomite rim's with in my case Goodyear Excellence 225/50 R17 94W. Found these to be very poor in cold and wintry conditions, compared to my previous Octavia I 4x4 & Golf V 4motion that ran on 205/55 R16 91V.

Switched to winters Christmas week after coming close to an accident trying to descend a hill road in fairly heavy snow at low speed; back over took front, engine cut out and we slid several yards backwards before coming to rest in a grass bank.

Rim's ordered through the dealer @ £147 for set (Yeti = 7J 16) and tyres from mytyres My link. Assembled and fitted locally for £30. Fully assembled tyre and rims are available from mytyres but at the time it worked out cheaper to get things separate.

VAG wheel bolts are designed to fit both VAG alloys an steel rims, so only need to change if you used non VAG parts maybe. Not sure if mytyres use official rims or third party. I know some look at ebay for second hand VAG steel rims.

Decided for me anyway new genuine parts was the way forward, and the Nokians were recommend to me and so far yes they are very good. Plus unlike from some manufactures they are available in the required minimum 94 load index.

Regards,

TP