Volkswagen Golf IV electronic differential.

[Parnelli Bone]

I'm reading about Mk. IV Golfs lately when i found this interesting tidbit at www.nctd.com (a review site for cars).



GLS and GTI models come with Volkswagen's Anti-Slip Regulation system (ASR), which detects wheel slippage and applies braking force to that particular wheel. Working with an Electronic Differential Lock at speeds below 25 mph, ASR controls throttle response to maximize traction and minimize slipping for enhanced driver control in tight cornering situations. Pressing a button in the center of the dash turns ASR off.

Okay, ignore the ASR stuff.

I thought the "electronic differential lock" was interesting. I notice in GT4 these Golfs exit corners with extreme grip and hardly any wheelspin. Certainly, no inner-tire wheelspin is present while the car is powered anywhere less than 250 horses. It makes me think PD took this diff into consideration when they modeled the Golf.

The thing is, i haven't been able to find any other sites that talk about it at all. Anyone familiar with it?

 

[Leonidae]

try googling VW 4Motion.. that should bring up some answers since as far as I know, that diff is part of the system.

 

[Parnelli Bone]

try googling VW 4Motion.. that should bring up some answers since as far as I know, that diff is part of the system.

Ah. Cool, thanks.

 

[Rotary Junkie]

This EDL is not - as the name suggests - a differential lock. Sensors monitor wheel speeds, and if one is rotating 100 rpms or more than the other (i.e. slipping) the EDL system momentarily brakes it. This effectively transfers all the power to the other wheel,[1] but still employs the open differential, which is the same as on cars without the EDL option.


~From Wiki.

 

[Philly]

Does this do similar things to the current ESP system in the MKVs?

 

[Keef]

Or they could just use a relatively cheap and simple limited slip differential. Ahhh, German engineering, answering questions nobody asked...

 

[Parnelli Bone]

This EDL is not - as the name suggests - a differential lock. Sensors monitor wheel speeds, and if one is rotating 100 rpms or more than the other (i.e. slipping) the EDL system momentarily brakes it. This effectively transfers all the power to the other wheel,[1] but still employs the open differential, which is the same as on cars without the EDL option.


~From Wiki.

So you're saying that nctd website quote is wrong? There is not an electronic differential? Weird. I wonder why they would call it an EDL, then.

I read somewhere that the new Challenger is supposed to have an electronic differential as well (if i remember correct) rather than an old-fashioned but predictable mechanical limited-slip. 👎

 

[FoolKiller]

Does this do similar things to the current ESP system in the MKVs?

This is my only problem with Volkswagen. We have ESP and ASR. They give these huge descriptions of what they are and what they do with fancy sensors and whatnot.

At the end of the day one is just stability management and the other is traction control. The icon ion my Rabbit that flashes when I get wheel spin is the same traction control icon that is on all cars, but they give it a fancy name.

My dealer was going over it and he actually said, "That's just VWs stability management and traction control systems."

So you're saying that nctd website quote is wrong? There is not an electronic differential? Weird. I wonder why they would call it an EDL, then.

VW loves their electronic systems and names them electric <whatever it does>. Like, I do not have power steering, I have Electronic steering assist, or something like that. And I have something like electrical assist brake management (it reads how urgently I am pushing the brake pedal and reacts before I have fully extended my leg/ankle).

Here are their fancy explanations for these diffrent stability systems, straight from the Das Auto magazine (free magazine for VW ownesr) site.
http://www.dasautomagazine.com/2008/v46n02/winter.aspx

ESPecially important

ESP®, or Electronic Stability Program, uses sensor inputs from the Antilock Brake System (ABS), which combines inputs with other sensors throughout the vehicle to apply precise, individual braking pressures to each wheel. Doing this helps make sure the vehicle stays on its intended path &#8211; that is, &#8220;where you&#8217;re steering it.&#8221; It&#8217;s a good thing to have, especially in inclement weather.

The Insurance Institute for Highway Safety (IIHS) has stated that electronic stability could prevent nearly one-third of all fatal crashes and reduce rollover risk by as much as 80%. To this end, Volkswagen gives a big thumbs-up, having already equipped all its 2009 model-year vehicles with ESP standard. Volkswagen is the only make in the U.S. to offer ABS and ESP standard, brand-wide for the 2009 model year.

The sum of das parts

It&#8217;s the little things, or so it&#8217;s been said. Volkswagen models feature numerous standard and available features to help keep you safe, cozy and in control&#8212;starting with knowing how cold it actually is with an outside temperature indicator and a snowflake symbol on your driver information display to indicate icy road conditions. How warm it gets inside is up to you, with features like heated seats and automatic climate control.

A differential you can feel

Electronic Differential Lock (or EDL) is a system that monitors the rotation of the driven wheels below speeds of 25 mph. If one of the wheels begins to slip&#8212;which can happen on icy, snowy roads&#8212;the system synchronizes the rotation of both wheels, thereby maximizing traction for accelerating.

Anti-Slip Regulation (ASR) also monitors rotation of the driven wheels, but at all speeds. When wheel slippage occurs during acceleration, ASR regulates throttle input and applies brake pressure to the slipping wheel to minimize the loss of traction. EDL and ASR are available on all Volkswagen models.

See, they could use standard terms, but no.

EDIT: all that said, it must work because my insurance company, Liberty Mutual, has special discounts for VW owners.

 

[///M-Spec]

So you're saying that nctd website quote is wrong? There is not an electronic differential? Weird. I wonder why they would call it an EDL, then.

I read somewhere that the new Challenger is supposed to have an electronic differential as well (if i remember correct) rather than an old-fashioned but predictable mechanical limited-slip. 👎

No, what Rotary Junkie is saying is the EDL name is something of a misnomer.

EDL uses individual wheel braking to allow an OPEN differential to behave in a manner similar to a LIMITED-SLIP differential (which are more complex and costly). The reason it is a misnomer is because EDL does not actually "lock" the differential in a traditional, mechanical sense. It slows a spinning wheel by applying the brakes, thus driving more torque to the other wheel, which hopefully is not spinning. But some wheel torque is still being wasted. A "true" LSD uses mechanical clutch plates or gears to couple the driven wheels and can bias torque from one side to the other.

EDL is a cost effective solution that works fine for most situations, whereas a true LSD is money no object performance solution. For example, a 'plain' Porsche 911 Carrera has an open rear diff, whereas the GT3 has an LSD.


M