Haldex Clutch Pump

[Yety]

Thanks for the clarification. So off road mode is disabling electronics like ABS, EDL, ESP and limits throttle to 2500 rpm? But the key requirement for traction over rough terrain is still handled automatically through the Haldex unit? With due allowance for tyre and wheel size differences, will a Yeti 4X4 and its Haldex power sharing off road come close to older Landrovers with 4WD drive engaged and diff lock? Sometimes, I see automatic control as a way of idiot proofing which can get in the way of an experienced  driver using their skills.

 

I agree on the need for a warning. But a warning that puts on MIL lights and gets the car into 'limp home' or' take to garage' mode is not something I would want. One day cars will have inbuilt diagnostics output that can show on the mfd. Then the buying public will really see how reliable their cars are.

 

 

No. I think you may have misread EJStubbs above.

 

The electronic gizmos are not disabled, actually the ABS acts more aggressively when the off road button is pressed to control wayward spinning wheels.

 

Old S1/2/3 Series had a solid drive when selected, but no diff-locks. More modern sorts, eg LR90 etc, have a centre diff which runs open most of the time , but can be locked up. Both axles have open diffs.

 

The Yeti can't really be compared to a LR product as it hasn't got the ground clearance, but it contains the elements of a software package similar to a modern JLR product.

 

I don't know if anyone has jacked a Yeti up and fitted MT tyres, but why would you.

The Yeti is a very clever 4x4 shopping car - that's all. Just drive it and enjoy.

I drive both sorts in different circumstances :wonder:  There's no real point in trying to make comparisons.

[Llanigraham]

If I remember rightly there is an excellent description of what the ORB does in the Handbook.

[ejstubbs]

Indeed there is: pages 129 to 131 in the November 2015 edition (available to download here).  It includes the warning: "But even with OFF ROAD mode activated, your vehicle is never a true SUV."  Whatever a 'true SUV' might be supposed to be - I assume they mean something like a LR Defender, or a Toyota Landcruiser.

 

Off Road is meaning when you go down steep hills, it keeps the brake pressure on the pedal for you to stop the car running away with itself, i.e. it will release brakes per wheel to get down a steep hill safely (human cannot do this)

 

That is but one of the functions enabled by the ORB - although, along with the start off assist, it is one of the easiest ones for the owner to 'verify'.  It's also quite a good trick to be able to make the car speed up by pressing the accelerator when the gearbox is in neutral!

 

Sometimes, I see automatic control as a way of idiot proofing which can get in the way of an experienced  driver using their skills.

 

Anyone who wants to exercise their off-road skills can buy a more appropriately-equipped car.  As Yety said, the Yeti isn't meant to be a full-on, go-absolutely-anywhere off-roader, although for a reasonably refined and civilised day to day car it has a significantly greater capacity to deal with difficult conditions 'under foot' than the majority of normal road cars.

 

Which reminds me: I wonder if my dashcam still has the video it must have shot of the Audi that I followed (at a judicious distance) up my street on Saturday just after a snow flurry - with his front wheels spinning like crazy, he left astonishing zig-zag patterns in the snow as he struggled for grip and just managed to make forward progress at approximately the pace of an asthmatic ant with a load of heavy shopping.    (Did I feel at all smug, trundling along happily behind without a care, on my winter tyres?  Too bl**dy right I did!)  A few minutes later I looked out of the front window and saw a BMW struggling similarly, rear wheels a-blur.

[ejstubbs]

P.S. Graham: I assume that is you also posting on the "Serious accident" thread in the RailUK forums?  (I've not been posting there myself, but I have been reading with a mixture of interest and sadness.)

[Ryeman]

In Australia there are 'roads' and 4WD 'tracks' and there are very few tracks in our 'High Country' that you would take a Yeti on unless you were wealthy, careless and had a backup vehicle to get you back to civilisation.

It just doesn't have enough ground clearance.

[Llanigraham]

P.S. Graham: I assume that is you also posting on the "Serious accident" thread in the RailUK forums?  (I've not been posting there myself, but I have been reading with a mixture of interest and sadness.)

 

I use the same name on lots of forums, so yes, although for how much longer I'll be on there is a different manner.

Too many people on there who know naff all about the railway, using it as an excuse to knock the railway all the time.

[voxmagna]

Hi, I'm posting my simple question here for help because this is a current Haldex thread:

 

I want to know what oil to put in my Haldex unit, if it has a filter (non is on the Yeti parts list) and where to get a filter and oil at a fair price. The parts are different across Haldex generations.

 

I need to confirm which Haldex unit is fitted on MY2012, either Gen IV or Gen V. Can I tell from a vcds scan? Is there anything on the unit itself, VIN plate or visual that confirms its generation?

 

There are Haldex oil and filter kits sold and a special crank spanner (is this for my unit?). I've found some Borg Warner exploded views showing a filter in various places. But first I need to know what is relevant to my generation unit. I have read that oil pump pressure and d.c motor current rises if the internal filter gets blocked, causing pump motor failure. Therefore if a filter is fitted, changing it must be an important maintenance operation (every 20K?). If there is a nylon gauze type filter, does it only need to be removed and cleaned explaining why it is not a normal service replacement? I have met manufacturer claims of 'fitted for life, not a service item before' and I am always sceptical.

Edited 18 February, 2016 by voxmagna

[muddyboots]

Hi, I'm posting my simple question here for help because this is a current Haldex thread:

 

I want to know what oil to put in my Haldex unit, if it has a filter (non is on the Yeti parts list) and where to get a filter and oil at a fair price. The parts are different across Haldex generations.

 

I need to confirm which Haldex unit is fitted on MY2012, either Gen IV or Gen V. Can I tell from a vcds scan? Is there anything on the unit itself, VIN plate or visual that confirms its generation?

 

There are Haldex oil and filter kits sold and a special crank spanner (is this for my unit?). I've found some Borg Warner exploded views showing a filter in various places. But first I need to know what is relevant to my generation unit. I have read that oil pump pressure and d.c motor current rises if the internal filter gets blocked, causing pump motor failure. Therefore if a filter is fitted, changing it must be an important maintenance operation (every 20K?). If there is a nylon gauze type filter, does it only need to be removed and cleaned explaining why it is not a normal service replacement? I have met manufacturer claims of 'fitted for life, not a service item before' and I am always sceptical.

It's Gen 4.

You can get the oil from your dealer or - like I did - from TPS (probably cheaper). Can't remember the part number but have the bottle at home somewhere.

Be careful you (or whoever does the change) changes the right oil - the Haldex clutch and the rear diff use separate oil, of different types, but are in the same housing. So make sure the right drain/fill holes get used

I used a large syringe and some plastic tubing to suck new oil from the bottles then squirt it into the fill point.

Yes there is a filter but it's a pain to get to and not scheduled for replacement. I set out with the idea of changing it, but decided not to in the end - just replaced the oil. Would be interested to see if you do change it. I was worried about buggering something up trying to get the filter out, and not being able to reassemble.

This thread has some excellent photos of the drain/fill points:

http://forums.vwvortex.com/showthread.php?5692616-VW-Tiguan-2009-Changing-Haldex-Differential-Manual-Transmission-and-Engine-Fluids

Edited 18 February, 2016 by muddyboots

[dbg400]

Just got back from the dealers. The haldex clutch pump has failed - having ruled out wiring & other issues. So it's going back at the end of the month to be replaced under warranty. It's a 3-4 hour job, so with the parts I think that will come to more than the extended warranty cost.

 

One other side effect of not having the rear wheel drive is having to brake harder. I've obviously got used to the rate it slows down in-gear before applying the brakes (coming up to junctions or slowdown in traffic) and I'm finding I've got too much momentum!

[voxmagna]

It's Gen 4.

You can get the oil from your dealer or - like I did - from TPS (probably cheaper). Can't remember the part number but have the bottle at home somewhere.

Be careful you (or whoever does the change) changes the right oil - the Haldex clutch and the rear diff use separate oil, of different types, but are in the same housing. So make sure the right drain/fill holes get used

I used a large syringe and some plastic tubing to suck new oil from the bottles then squirt it into the fill point.

Yes there is a filter but it's a pain to get to and not scheduled for replacement. I set out with the idea of changing it, but decided not to in the end - just replaced the oil. Would be interested to see if you do change it. I was worried about buggering something up trying to get the filter out, and not being able to reassemble.

This thread has some excellent photos of the drain/fill points:

http://forums.vwvortex.com/showthread.php?5692616-VW-Tiguan-2009-Changing-Haldex-Differential-Manual-Transmission-and-Engine-Fluids

Thanks that link is excellent, It should be in the sticky data for the Haldex. The requirement for different oils in the Diff and Haldex now explains why their parts lists different oils and capacities, from memory one was 1litre the other nearly 1/2 litre. I have had experience of expensive BMW motorcycle ABS pump motors failing. The problem is these hydraulic pumps can be extremely small and hard worked, often with puny d.c (model!!) motors which run at high rpm and current for their size. The high current takes its toll on the poor brush design and commutator. Any increased stress load and current can significantly reduce motor life. If there is a route open for ventilation, water and road grit can penetrate. High pressure fuel pump motors can fail the same way.

 

I found a good suggestion to monitor current feeding the Haldex unit through the fuse. Apparently, the fuse is a much higher value than the pump mean running current. I haven't studied the wiring diagram yet, but I have a suspicion of the problem: The fuse feeding the Haldex pump is shared with other items - probably those on FWD Yetis. Therefore they rate the fuse for the combined amperage load connected to it. This is really bad electrical design for motors, because when they stall or get too much load, their load current rises very fast and burns the motor first before the fuse. If their fuse is exclusive to the Haldex unit and rated just above the mean pump current, any filter blockage or motor stall would blow the fuse saving the motor. It will take me some time to work out the physical wiring, But if I can put the Haldex pump on an unused fuse, easily or fit a lower rating in-line fuse or poly cut out fuse I will.

 

I am definitely up for having a go at removing the filter in Spring on the basis that if the pump motor fails, it would probably have to be looked at anyway and the motor replaced. I found a Volvo filter part which might be the one. I was really hoping somebody had found an identification tag on the Haldex unit carrying the part number. Even on Gen 4 units there are variations.

 

If your vehicle is under warranty, then it is only logical to have the dealer sort it out. The problem could be the same thing happens again when there is no warranty. As MT2012 Yeti is outside of warranty, I will be looking at the motor current, the filter and fluid changes whilst it is on the ramps. Better safe now than sorry later.

[dbg400]

I took the car in this morning and collected it late afternoon. It's had a new haldex clutch pump, all done under warranty. I've not had a chance to test it yet, as the traffic back from Harrogate was the usual slow crawl, but I should find out tomorrow. Judging from the amount of wheelspin I've had at junctions & roundabouts I've obviously relied a lot on the 4x4 system without realising it.

[Yety]

I took the car in this morning and collected it late afternoon. It's had a new haldex clutch pump, all done under warranty. I've not had a chance to test it yet, as the traffic back from Harrogate was the usual slow crawl, but I should find out tomorrow. Judging from the amount of wheelspin I've had at junctions & roundabouts I've obviously relied a lot on the 4x4 system without realising it.

 

Good news then.

 

I'm not being funny, but wheel spin at junctions and roundabouts? To get any sort of wheel spin you normally have to have wet roads and diesel spillage . I can sometimes get a little wheel spin in my MG on wet roads, but only if I "drive like I stole it". 

 

To comment on the Haldex fluid, I changed mine myself recently as it fell between Skoda service intervals. The fluid came out very clear, very nearly the same colour as the new fluid but with a few black blobs. Closer inspection showed that the blobs were like jelly, and mushed up when crushed between your fingers. I thought about a filter, but they seem very expensive strangely.

Whilst on the subject of Haldex, I'm now convinced the lurch, particularly on pulling/reversing away from rest on lock is down to a "rough" action of the clutches. I've had all four wheels jacked up in the air and an onlooker watching, tried it on the recent snow/ice etc. I think the software is less refined that in say a JLR product, but still works just the same. Might well be a cost saving?

[dbg400]

It's been very wet, and this morning icy. The worst is the build up of road salt making junctions quite slippery places.

 

It was no problem in the little 60bhp Citigo I had a courtesy car, but there is a lot of torque to be pushed through just the front wheels on the Yeti, and I have got used to using it. I had the same problem in winter, at the same junctions & roundabouts, with my old Octy when the tyres were worn, but that was with half the power of the Yeti.

[freedie]

Yes. I can easily induce the ESP light at junctions and roundabouts with a brisk skoda entry. Thank God for 4x4 working. Really glad yours is OK again dbg400 and at no cost.

[muddyboots]

The fluid came out very clear, very nearly the same colour as the new fluid but with a few black blobs. Closer inspection showed that the blobs were like jelly, and mushed up when crushed between your fingers.

Mine was exactly the same, I had the mushy blobs too

 

I'm not being funny, but wheel spin at junctions and roundabouts? To get any sort of wheel spin you normally have to have wet roads and diesel spillage .

It's quite easy in a remapped CR170

The great thing about 4x4 is that you *can* pull away more quickly without fear of wheelspin, and you get used to it.

Roads have been really slippy recently, being cold and covered in salty grime. Couple that with the unexpected loss of 4wd...wheelspin aplenty!

Edited 1 March, 2016 by muddyboots

[dbg400]

Normal service has been resumed Wet & muddy roads abound today, and no wheelspin or traction light flicker.

[freedie]

Excellent and exacto...

[zar]

Thanks that link is excellent, It should be in the sticky data for the Haldex. The requirement for different oils in the Diff and Haldex now explains why their parts lists different oils and capacities, from memory one was 1litre the other nearly 1/2 litre. I have had experience of expensive BMW motorcycle ABS pump motors failing. The problem is these hydraulic pumps can be extremely small and hard worked, often with puny d.c (model!!) motors which run at high rpm and current for their size. The high current takes its toll on the poor brush design and commutator. Any increased stress load and current can significantly reduce motor life. If there is a route open for ventilation, water and road grit can penetrate. High pressure fuel pump motors can fail the same way.

 

I found a good suggestion to monitor current feeding the Haldex unit through the fuse. Apparently, the fuse is a much higher value than the pump mean running current. I haven't studied the wiring diagram yet, but I have a suspicion of the problem: The fuse feeding the Haldex pump is shared with other items - probably those on FWD Yetis. Therefore they rate the fuse for the combined amperage load connected to it. This is really bad electrical design for motors, because when they stall or get too much load, their load current rises very fast and burns the motor first before the fuse. If their fuse is exclusive to the Haldex unit and rated just above the mean pump current, any filter blockage or motor stall would blow the fuse saving the motor. It will take me some time to work out the physical wiring, But if I can put the Haldex pump on an unused fuse, easily or fit a lower rating in-line fuse or poly cut out fuse I will.

 

I am definitely up for having a go at removing the filter in Spring on the basis that if the pump motor fails, it would probably have to be looked at anyway and the motor replaced. I found a Volvo filter part which might be the one. I was really hoping somebody had found an identification tag on the Haldex unit carrying the part number. Even on Gen 4 units there are variations.

 

If your vehicle is under warranty, then it is only logical to have the dealer sort it out. The problem could be the same thing happens again when there is no warranty. As MT2012 Yeti is outside of warranty, I will be looking at the motor current, the filter and fluid changes whilst it is on the ramps. Better safe now than sorry later.

Volvo filter is compatible to all Skoda Haldex gen.4 systems.part No. is:Volvo 31325173.Filter is absolutely the same,but aluminium cap is slightly different and better to use the present one also the same is with plastic pad(totally different).

[wibble]

I can tell my 4x4 system is working.

4 new tyres last year and now the rear are at 3mm while the front are at 6mm

So I'm pretty sure my system is doing its work.

[Ryeman]

I can tell my 4x4 system is working.

4 new tyres last year and now the rear are at 3mm while the front are at 6mm

So I'm pretty sure my system is doing its work.

That's certainly not my experience.

The engine/ DSG mass is over the front wheels which do most of everything - braking, steering and accelerating.

[TruckbusUK]

I can tell my 4x4 system is working.

4 new tyres last year and now the rear are at 3mm while the front are at 6mm

So I'm pretty sure my system is doing its work.

Mmmm not sure thats how any version of a Haldex unit works. usually is 1% or 2% to the rear unless slip is detected, then the "gubbins" will move power to the rear until it detects no slip and "normal" service will be resumed ... ie 98% to the front and 1% or 2 % to the rear.

That coupled with little weight over the rear wheels compared to the fronts I think you have another problem if your rears are wearing at that level in normal use.

 

I know its not a Yeti I drive but that's certainly how my Volvo works using a Haldex Gen IV unit, and my tyre wear is only ever 1mm'ish different over the life of the tyres.

 

Hope it helps

Edited 29 April, 2016 by TruckbusUK

[ernieb]

Probably got it wrong but I thought the split was 90:10 front to rear in normal operation??

[Ryeman]

I can tell my 4x4 system is working.

4 new tyres last year and now the rear are at 3mm while the front are at 6mm

So I'm pretty sure my system is doing its work.

Tyre weren't rotated?.

[EvoT]

The sentence below from a previous post on this subject

 

One day cars will have inbuilt diagnostics output that can show on the mfd. Then the buying public will really see how reliable their cars are.

----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

YES ! and when we buy a 4x4 Yeti on the used car market a buyer can check and will know all is well with the car along with all the other gizzmo filled makes !

 

It should have ( the diaognostics ) been installed on the MFD in the first place otherwise you are in great danger of buying a 'lemon' if you do not buy from a dealer with some form of insurance cover on the car and given a printout from the diagnostics in the car to show there are no fault codes before you sign on the dotted line.

 

I wonder how many people ask for this or about it before they buy used ???? ' I'll buy the car but I require a print out first of the fault codes, if there are  any, before I say yes

 

In fact a printout from the diaognostics of every, or any make of vehicle,with any form of ''vehicle electronic management system installed'' should be available to a possible buying  customer.

The printout should be placed in the vehicle for you to inspect before you buy, wether the vehicle is used or new, to show there are no fault codes.They should not be cleared and reset you should have a historic log ( if this is possible ) issued along with the latest printout codes ( If any ).

 

This should be a standard across the industry under 'good trading practice' so people are not unintensionally  misled.

 

Even main dealers now, are not up to speed with all the items fitted to modern cars, very few sales people are vehicle technicians, have you noticed how sales, these days,has become 'leaving the customer alone with the car to make up their mind '??

 

If you are selling private you will need to have a printout produced for the sale, time and dated with miledge, the same as a dealer, maybe this could be done by mot stations or The RAC and AA at home ? to safeguard buyers and sellers.

 

At present I would never buy a Yeti 4x4 from any other source than a Skoda dealer after all I have read on the possible faults with the car and I would never buy one from a private seller as there is just so many items to check before you buy. The same goes for any other make of vehicle I am not just picking on  Skoda !!

[TruckbusUK]

Tyre weren't rotated?.

The wear would be the other way round  .... would it not?  Fronts worn worse than the rears.

I would be very doubtful if any "part-time" all wheel drive/ front wheel drive car wore the rears faster than the fronts.

 

@ Wibble .... is the wear on the rear tyres even?