Limited Slip Differential - Seat Leon 2.0TSI FR

[Razoo]

The later Leon 2.0TSI FR has a LSD (Limited Slip Differential). It seems this is an electronic LSD that works in conjunction with the ABS. I haven't found a comprehensive description of how the LSD works, but I assume it applies the brake to the wheel that has lost grip, thereby transferring the power to the other wheel. If this is correct, where does the LSD get the hydraulic pressure from to apply the brake? Is there a pressurised reservoir of brake fluid somewhere, and if so, how is it pressurised? Electric high-pressure pump?

Does anyone know how the Leon FR electronic LSD system works?

Does anyone know how effective the electronic LSD is? Is it worth having?

Thanks,

Razoo

 

[SEATLEONUK]

Definitive

The later Leon 2.0TSI FR has a LSD (Limited Slip Differential). It seems this is an electronic LSD that works in conjunction with the ABS. I haven't found a comprehensive description of how the LSD works, but I assume it applies the brake to the wheel that has lost grip, thereby transferring the power to the other wheel. If this is correct, where does the LSD get the hydraulic pressure from to apply the brake? Is there a pressurised reservoir of brake fluid somewhere, and if so, how is it pressurised? Electric high-pressure pump?

Does anyone know how the Leon FR electronic LSD system works?

Does anyone know how effective the electronic LSD is? Is it worth having?

Thanks,

Razoo

I think you already know the answer, mate. SEAT refer to as XDS, its an Electronic Differential Lock system. It gets the pressure from the braking system, there is no additional brake fluid reservoir.
The system is not as good as a mechanical LSD as most people on here will tell you. You can barely feel it working when the car is pushed...

I know my answer my not be as 'comprehensive' as you would like but, it is absolutely definitive.

 

[AndrewJB]

When i was at Seat UK Media day i spent a fair few hours in the Cupra R


My Leon has Eibach Suspension so corners better than standard but the Cupra R Felt far superior and more stable in the corners i put that down to the XDS


Of course the XDS will be pants compared to a Mechanical LSD but compared to not having XDS its good

 

[jezyg]

The later Leon 2.0TSI FR has a LSD (Limited Slip Differential). It seems this is an electronic LSD that works in conjunction with the ABS. I haven't found a comprehensive description of how the LSD works, but I assume it applies the brake to the wheel that has lost grip, thereby transferring the power to the other wheel. If this is correct, where does the LSD get the hydraulic pressure from to apply the brake? Is there a pressurised reservoir of brake fluid somewhere, and if so, how is it pressurised? Electric high-pressure pump?

Does anyone know how the Leon FR electronic LSD system works?

Does anyone know how effective the electronic LSD is? Is it worth having?

Thanks,

Razoo

XDS is an advanced electronic differential lock, linked to the Electronic Stabilisation Programme (ESP). The Idea is to mimic a mechanical LSD and it is very nearly there BMW use a similar system on there 135i Coupe.

In moments of fast cornering the XDS gives out exactly the right amount of power, providing brake pressure on the inside wheel to prevent wheel spinning. The result is better traction and a reduction of any tendency to under steer.

Simply gives a more agile, precise drive with better traction out of bends and reduced understeer and works very well IMO.I have never been able to actually detect it is working.

 

[Cuprarob112]

What I have experienced so for is that the electronic lsd on an R works quite good in road conditions (without becoming too traceable. On track it makes the car slower in bends (compared to a normal cupra but espacially compared to a mechanic version).
Personally I don't like these electronic safety measures too much but I guess in difficult situations they might be the difference between coming home safe and hitting something.

 

[tehguy]

It's not an LSD. As said it's an open differential with a clever traction control system which slightly brakes the inside wheel during hard, high speed cornering.

You can see/feel it work if you have one front wheel on a high traction surface and the other front wheel on a very low traction surface and try to drive. The wheel with no grip will spin for a bit and then the TC will apply the brake on that wheel, thus forcing the wheel with good grip to spin.

It's similar to left foot braking but the advantages are 1) the car does it for you and 2) it can apply the brakes individually.

 

[GrahamFR]

does anyone know if when the xds is working, does the traction control light flash, cos i have no idea if i have ever experienced it, i know my CR handles better than my PD, but not by much and i have a better ARB on this one, so how do i know if its working? (without launching into a corner at full speed and assuming its going to work...)

 

[dukebox9reg]

surely if doing track time with this kinda diff its going to cook the brakes pretty quickly?

 

[tehguy]

Try it yourself, just do what I suggested above. I found the warning light is a bit hit and miss really, back in the winter snow I had it kick in quite a lot of times, sometimes you can have one wheel spinning for ages before it flashes the light, other times it will flash before I even realised it lost traction.

 

[Al]

I have it in my FL Cupra, and have to say it feels no different to my Pre-FL Cupra with no XDS. Also have to say that mechanical LSD's are probably over-rated too (talking from experience), but on a car like the Cupra/Cupra R, SEAT should have fitted a mechanical LSD as standard.

 

[GrahamFR]

yes but isnt that just the traction control system?

 

[Razoo]

XDS (Limited Slip Differential) - Seat Leon 2.0TSI FR

You can see/feel it work if you have one front wheel on a high traction surface and the other front wheel on a very low traction surface and try to drive. The wheel with no grip will spin for a bit and then the TC will apply the brake on that wheel, thus forcing the wheel with good grip to spin.

How well will the XDS perform on snow or ice? If both driven wheels are struggling for grip, will the XDS be still be effective?

Thanks,

Razoo

 

[Al]

It's not any more effective in the snow and ice than it is any of the rest of the time. My car got stuck in half an inch of snow in the winter.

 

[GrahamFR]

lol every leon i have owned has been rubbish in the snow, my old megane was loads better, no matter how many 3 letter acrynoms we have

 

[Razoo]

lol every leon i have owned has been rubbish in the snow, my old megane was loads better...

My RWD (Rear Wheel Drive ) automatic Mercedes really is rubbish in the snow. It stranded me on a very gentle slope last year. I've never been stuck in snow in a FWD (Front Wheel Drive - not to be confused with Four Wheel Drive, which is written 4WD! ) car. I stopped using the Mercedes when there was snow around and nicked Mrs Razoo's 1.8 Ford Focus instead. The Focus performed very well.

Why are Leons rubbish in the snow? Tyres too wide? I would have expected a FWD Leon to be at least as good in the snow as a FWD Focus. That said, my (briefly owned) Focus ST with its wide tyres and high power wasn't very good.

However, I would expect a 'Torvill & Dean' performance from a Leon FR with XDS!

... no matter how many 3 letter acrynoms we have

Surely you mean "...no matter how many TLAs we have."

Maybe this forum should have a searchable index of common acronyms 'cos not everyone who searches for information will have a degree in 'nerd-speak'.

Razoo

 

[jezyg]

Only one decent answer to snow/ice and that is fitting winter tyres. Wide low profile tyres are going to be pretty poor in winter conditions anyhow as they don't cut through the snow as well as narrow profile tyres.

 

[Cuprarob112]

My Cupra on Vredestein Wintrac performs absolutely perfect in snowy conditions and give all the control you may expect from a front wheel driven car.... everything else is up to the skills and the common sense of the driver.