XDS, or EDL, or XDL+ electronic differential lock - is it supplied at all in the UK?

[nickcoll]

My current 2013 Octavia SE 4x4 estate is a great handling car, and one of the things which makes it so is the combination of 4 wheel drive and the XDS (as it was called at the time) electronic diff lock. You can actively feel the way in which it reduces understeer and as a result you can drive the car enthusiastically (but always within the law!) and it grips, in combination with the 4x4, fantastically well.

 

I am sure it is also part of what has made other models handle well - I know that with the Mk 3 models it was fitted to many models at various times. I have assumed that it was always a standard fitment on the Mk 3 VRS, but also to some other models.

 

I was however REALLY shocked to read the new Autocar review of the VRS TDi with its 197bhp engine which says multiple times through the review that this model was almost ruined by its lack of "any form of limited-slip differential". This is surely craziness on Skoda's part - how can a car with a highly torquey front-wheel-drive engine ever hope to be sporty without some form of LSD?

 

The article also says that the 4x4 model doesn't need a LSD - well, maybe it doesn't need it, but from my experience with my car it definitely benefits from it by very effectively reducing understeer.

 

This may be a total showstopper for me in getting a Mk4 - this would be a very big backward step in driving enjoyment for me. As a result I have carefully examined the brochure and there is no mention at all of whether any models get the current version of LSD - called either EDL or XDL+ (two different levels of effectiveness?) according to the Octavia Mk4 owners manual - which also gives nothing away about which cars get it fitted. I have also gone through the "Build Your Own" system and in there I have not seen any mention of it either. I have tried Googling EDL and XDL+ and nothing comes up apart from links to the owners manual.

 

Does anyone know what the situation is with regard to this? The MQB platform obviously still has an electronic LSD available, since it's mentioned in the manual. Has it been de-selected for all UK models by Skoda UK, or do some models get it but not others, and, if so, which models get it and which don't?

 

Does anyone who has a Mk 4 VRS know if their car has XDL+ fitted?

[parsey83]

Mk4 vrs Tsi 245 has the electronically controlled mechanical lsd. I think the other vrs models get the e-lsd which uses brake pulsing to simulate the effects of a mechanical lsd

[Schtum]

3 hours ago, parsey83 said:

Mk4 vrs Tsi 245 has the electronically controlled mechanical lsd. I think the other vrs models get the e-lsd which uses brake pulsing to simulate the effects of a mechanical lsd

 

The Autocar test of the FWD vRS diesel stresses that the car doesn't have any electronic differential aids.  I wonder if it's a case of the software being in the ECU but not enabled.  This is certainly the case on several models of earlier cars such as my 2016 Yeti 150 TDI 4x4 which like all Yetis didn't have XDS enabled from the factory.  However, it's a relatively simple matter to enable it with VCDS.  

 

It would only take someone with a recent VCDS cable and a bit of knowledge to have a look to see if XDL can be enabled on the MK4 vRS Octavia. 

[DuncanW]

My understanding is that the petrol has a 'proper' mechanical LSD whereas the rest of the range have the 'pseudo' one that applies the brakes on the inside wheel to minimise slippage and possibly does some power shifting (I have the XDS on my Leon - not sure how much effect it has and whether the plus version is move effective.) Presumably the 4x4 does torque vectoring anyway so braking the inside wheel (done in software) is sufficient?

[nidza]

@nickcoll, you haven't really understood an article, so please let me explain.

 

First of all, each generation of Octavia has better driving assists, not worst or less. If you had before 4x4 TDI, current 4x4 TDI will perform better, in its electronic assist systems. 

 

Since Octavia 2, and ASR+ESP, all Octavias have some level of wheel anti-slip regulation, better in each generation - we were proud owners of O2, O3, O4.

 

What this article is stating, 4x4 doesn't have a mechanical LSD (called VAQ, electronically controlled), like it never had. Only front driven vRS petrol engine cars, in some versions, were equipped with VAQ (like Cupra, like GTI Performance) Other system previous generation had most definitely exist, plus they are, without exception improved. 

 

Now, after we clarified that you are not going to have backward step, but quite the opposite, let's talk hypothetically:

Would mechanical LSD be beneficial for 4x4 car? Yes , it absolutely would, much better then electronical, but to be honest, 99% of owners couldn't tell the difference, therefore, it doesn't make much sense.

 

Good luck with your purchase. 

[nickcoll]

Certainly the 'pseudo' one works very effectively with my 4x4 to reduce understeer so that it practically doesn't exist, with the car sliding sideways if it gets to that point (very wet or icy weather). I am reluctant to buy a new Octavia if it doesn't have that feature. Why fit it in the ECU and not enable it?

 

Andy why, for that matter, did Skoda submit a car for a road test that was so inadequate in this respect? Why not submit the 4x4 model which doesn't suffer from such embarrassing behaviour? What a missed opportunity - I can only assume that the people in their PR department don't know anything about their cars.

 

And finally, all of this speculation on what is fitted and to which models is very interesting, but why is there no way of knowing exactly what is fitted and to which models? The information seems to have been dumbed-down below an acceptable level.

[PetrolDave]

Or did the Autocar article refer only to there not being a physical limited slip differential without checking whether there was an electronic pseudo limited-slip differential?

 

Most magazine reviews cannot be relied upon to be completely accurate about the spec of the vehicle they are reviewing.

[Ootohere]

The systems fitted as standard work at UK NSL's, & at faster speeds than NSL's, but can not actually change the traction / friction available with the interface of the tyre to the road surface and if crap tyres or tyres not suitable for the conditions might be having to displace lots of water, drive on ice / black ice, on snow etc.

[nickcoll]

9 minutes ago, nidza said:

What this article is stating, 4x4 doesn't have a mechanical LSD (called VAQ, electronically controlled), like it never had. Only front driven vRS petrol engine cars, in some versions, were equipped with VAQ (like Cupra, like GTI Performance) Other system previous generation had most definitely exist, plus they are, without exception improved. 

 

I don't know why you are getting so worked up about this - it is pretty clear from my posts that I am entirely happy with the electronic LSD that my 4x4 has fitted. It doesn't need any more than that, but it definitely does improve its handling a lot. What I am frustrated about is the lack of information and what the Autocar article says is that the model they tested is not fitted with any form of LSD, which is why it comes over so badly with very poor traction off the line. If Skoda can do that with the VRS FWD, and omit any mention of it from their literature, it is surely valid to ask the question whether it has been deleted from the 4x4?

 

Your faith that the new model will be better in every respect is admirable, but before buying one I would like some evidence. What's wrong with that?

Edited 24 February, 2021 by nickcoll

[Ootohere]

If you go to the EV section and read about the Hyundai Ioniq 5 there is a link to an Autocar link yesterday.

 

What a load of guff written in the article by some journalist with not an actual clue what they read someplace then wrote about.

That is what you get from Haymarket Media Group publications and their journalists and editors.  A lack of understanding about vehicles and motor engineering and tech quite often.

[nickcoll]

5 minutes ago, PetrolDave said:

Or did the Autocar article refer only to there not being a physical limited slip differential without checking whether there was an electronic pseudo limited-slip differential?

 

Most magazine reviews cannot be relied upon to be completely accurate about the spec of the vehicle they are reviewing.

That could be the case. If so, once again I do wonder why Skoda submitted the FWD model for review rather than the 4x4. They should have known that it would be criticised for lack of traction given the level of torque the engine produces.

 

There is no clarity about what the two forms of LSD consist of that I have found anywhere. Presumably EDL = Electronic Diff Lock and XDL+ is the VAQ mechanical diff lock. Why not say it then, and be more explicit about which is used in which model?

[PetrolDave]

6 minutes ago, PetrolDave said:

Or did the Autocar article refer only to there not being a physical limited slip differential without checking whether there was an electronic pseudo limited-slip differential?

 

Most magazine reviews cannot be relied upon to be completely accurate about the spec of the vehicle they are reviewing.

 

1 minute ago, e-Roottoot said:

If you go to the EV section and read about the Hyundai Ioniq 5 there is a link to an Autocar link yesterday.

 

What a load of guff written in the article by some journalist with not an actual clue what they read someplace then wrote about.

That is what you get from Haymarket Media Group publications and their journalists and editors.  A lack of understanding about vehicles and motor engineering and tech quite often.

Seems that replying on an Autocar article (any magazine article?) might not be the best way forward - @nickcollwhy not ask either a Skoda dealer or Skoda UK the direct question about LSD or electronic alternatives that may or may not be fitted to Octavia IV models?

[Ootohere]

The systems have moved on.

There was ASR / TC and still is, that could come with XDS (EDL),  then there was XDS+ (EDL) then we get to VAQ.

 

As for the big power of the TSI's, TSI's with Hybrid or the TDI's.   What you often get is if wheelspin is detected and not controlled by the systems then you have what you have.

The simplest of the system was nipping brakes and maybe also cutting power / drive, and this still exists.

 

http://briskoda.net/forums/topic/329193-vrs-esc-tcs-edl-xds-dsr-asr-wtf

http://briskoda.net/forums/topic/214776-wtf-is-abs-edl-asr-esp-hhcetc

http://briskoda.net/forums/topic/289561-confuced-with-traction-control

 

 

 

Edited 24 February, 2021 by e-Roottoot

[nickcoll]

7 minutes ago, PetrolDave said:

 

@nickcollwhy not ask either a Skoda dealer or Skoda UK the direct question about LSD or electronic alternatives that may or may not be fitted to Octavia IV models?

Yes, I suppose I could do, although my experience with dealer salespeople is that they know very little to nothing about the technical aspects of the vehicles. Their eyes glaze over if I ask a question like this and they want to move on quickly to the next customer who doesn't ask what they consider to be difficult questions for which they don't know the answer!

 

Skoda UK - although I don't really know why it should be necessary to ask them about information that should be readily available, how would I go about contacting them about this?

[nickcoll]

6 minutes ago, e-Roottoot said:

As for the big power of the TSI's, TSI's with Hybrid or the TDI's.   What you often get is if wheelspin is detected and not controlled by the systems then you have what you have.

The simplest of the system was nipping brakes and maybe also cutting power / drive, and this still exists.

Yes, it is obvious that without 4x4 the electronic systems are inadequate for a torquey FWD-engined car.

[Ootohere]

There is a reason Salespeople know little, & that is because they are salespeople and some Sales Executive get invited to Launches of new models abroad or in the UK and Sales People from VW / Skoda / Haymarket Media Group (who launch vehicles for VW Group) who know little introduce them to the vehicles, as they do with Journalists.

 

Nobody taking and driving away cars checks the tyres pressures before road testing or knows if the cars are running 95 or 99 ron fuel.

They do not even know if cars are running a factory map.

(Some roadtest cars and the Tyre Pressure was as for being transporter on a transporter and still a 50psi as they might be from a PDI having been done as many new owners get when collecting a new car.)

Edited 24 February, 2021 by e-Roottoot

[PetrolDave]

3 minutes ago, nickcoll said:

Yes, I suppose I could do, although my experience with dealer salespeople is that they know very little to nothing about the technical aspects of the vehicles. Their eyes glaze over if I ask a question like this and they want to move on quickly to the next customer who doesn't ask what they consider to be difficult questions for which they don't know the answer!

 

Skoda UK - although I don't really know why it should be necessary to ask them about information that should be readily available, how would I go about contacting them about this?

I've never found any dealer sales person with decent product knowledge in the 40+ years I've been buying cars.

 

Skoda UK contact? see Skoda UK - Contact Us

[PetrolDave]

2 minutes ago, e-Roottoot said:

They do not even know if cars are funning a factory map.

When I worked for a car manufacturer it was well known within the engineering teams that the demonstrator of their new model definitely did NOT have a factory engine map, but all the reviews by journalists never asked the question or commented on how the demonstrator was so much quicker than their long term test cars?

Edited 24 February, 2021 by PetrolDave

[nickcoll]

3 minutes ago, PetrolDave said:

I've never found any dealer sales person with decent product knowledge in the 40+ years I've been buying cars.

 

Skoda UK contact? see Skoda UK - Contact Us

Quite!

 

Thanks!

[Ootohere]

@PetrolDave

They never drive to a public weigh bridge or get the car on corner weights.

 

Autocar testers used to do that though.  They did good Hot Hatch Comparisons back about 6 years ago with the likes of Focus ST, SEAT Cupra & VW Golf and caught out the fiction spec of VW compared to SEAT.

Edited 24 February, 2021 by e-Roottoot

[nickcoll]

For interest, here is the only text from the owners manual which talks about the diff locks:

 

Electronic Differential Lock (EDL)
EDL helps to stabilize the vehicle when driving on road surfaces with different grip under the individual wheels. EDL brakes a spinning wheel and transmits power to a different drive wheel.
Electronic Differential Lock (XDL+)
XDL+ helps to stabilize the vehicle during fast cornering by braking the inside wheel of the driven axle.

 

So much clearer now! That is all, no indication of which models either option is fitted to. Both seem to be electronic in nature, no mention of a mechanical diff lock.

 

As before I haven't found any references anywhere else at all (not on the website, not in the brochure, and not by Googling) to diff locks on any Octavia models. I have emailed Skoda UK and it will be interesting to see if they come back with anything.

[langers2k]

Things get confusing as there are many things at play here...

 

There are a multitude of technologies implemented by the ABS module including (but not limited to) ASR (Anti-Slip Regulation), EDL (Electronic Diff Lock), ESP (Electronic Stability Program) and XDS ("X" Cross Differential System). They all work to achieve slightly different things:

- ASR aka traction control, reduces engine power to control wheel spin

- EDL uses the brakes to transfer power to wheels with grip (brakes the spinning wheel to transfer power to the non-spinning wheel)

- ESP has acceleration sensors to compare the expected and actual car movement, it will use both power modulation and brakes to get the car back on the expected path

- XDS (torque vectoring) is an extension of the EDL+ESP systems, it'll use the inside brakes while turning to reduce wheel spin and maximise control/drive through and out of the corner

 

In short, these systems can modulate power and brakes (and haldex where fitted) to maximise grip and control. I would expect these fitted to all models of the MK3 and MK4 Octavia (some MK2 models did not get ESP as standard). Therefore, I'd expect the MK4 4x4 to handle things in a very similar fashion to your MK3 4x4, even more so as the MQB platform hasn't changed much between the two versions.

 

Now on to an LSD, as it turns out, no stock Octavia gets a 'true' LSD fitted...

 

The closest thing to a 'true' mechanical LSD is the VAQ (Vorderachsquersperre) which is an e-LSD. This is a open diff with a clutch pack on one the side to apply various amounts of lock. It's basically the haldex system which is normally used to adjust front/rear power ratios being used between the front wheels instead. It's only been fitted to higher power petrol engines so far.

 

Hopefully that's helped explain some of the technologies and acronyms...

 

Back to the article, I think it's just badly explained. As the TDi vRS 'only' has EDL/ESP/XDS, it's technically correct as it's not an LSD or even e-LSD. The fact that EDL is designed to achieve a similar result, namely transferring power to the wheel with grip, is beside the point

[nickcoll]

34 minutes ago, PetrolDave said:

When I worked for a car manufacturer it was well known within the engineering teams that the demonstrator of their new model definitely did NOT have a factory engine map, but all the reviews by journalists never asked the question or commented on how the demonstrator was so much quicker than their long term test cars?

Would any VAG company dare to risk that now? If it is true, then it is even more stupid to do it to a FWD car which would just increase the traction problems.

[nickcoll]

1 minute ago, langers2k said:

There are a multitude of technologies implemented by the ABS module including (but not limited to) ASR (Anti-Slip Regulation), EDL (Electronic Diff Lock), ESP (Electronic Stability Program) and XDS ("X" Cross Differential System). They all work to achieve slightly different things:

- ASR aka traction control, reduces engine power to control wheel spin

- EDL uses the brakes to transfer power to wheels with grip (brakes the spinning wheel to transfer power to the non-spinning wheel)

- ESP has acceleration sensors to compare the expected and actual car movement, it will use both power modulation and brakes to get the car back on the expected path

- XDS (torque vectoring) is an extension of the EDL+ESP systems, it'll use the inside brakes while turning to reduce wheel spin and maximise control/drive through and out of the corner

 

In short, these systems can modulate power and brakes (and haldex where fitted) to maximise grip and control. I would expect these fitted to all models of the MK3 and MK4 Octavia (some MK2 models did not get ESP as standard). Therefore, I'd expect the MK4 4x4 to handle things in a very similar fashion to your MK3 4x4, even more so as the MQB platform hasn't changed much between the two versions.

 

Quote

Now on to an LSD, as it turns out, no stock Octavia gets a 'true' LSD fitted...

 

The closest thing to a 'true' mechanical LSD is the VAQ (Vorderachsquersperre) which is an e-LSD. This is a open diff with a clutch pack on one the side to apply various amounts of lock. It's basically the haldex system which is normally used to adjust front/rear power ratios being used between the front wheels instead. It's only been fitted to higher power petrol engines so far.

 

 

That's really helpful although we still don't know which models are fitted with what. And if the TSi VRS gets the VAQ, why don't Skoda publicise the fact? And I still wonder why they sacrificed the TDi VRS FWD-only in that way!

[langers2k]

6 minutes ago, nickcoll said:

That's really helpful although we still don't know which models are fitted with what. And if the TSi VRS gets the VAQ, why don't Skoda publicise the fact? And I still wonder why they sacrificed the TDi VRS FWD-only in that way!

 

I would assume that all MK3 and MK4's have the electronic aids I mentioned given ESP is mandatory. I have no idea why they aren't publicised more clearly.

 

As for the VAQ and the TDi, it seems to be the current VAG plan...

 

AFAIK, the higher powered TDi Golf and Leon also don't get a VAQ option. VAG probably decided there is a minimum power requirement to benefit from the VAQ and the TDi's don't make the cut. It could be purely cost related as the TDi's are already more expensive. Otherwise, it could be that the TDi's aren't considered true performance versions (no offense intended!)