electronic differential lock test

electronic differential lock (edl)

The following videos show how Electronic Differential Lock (also known as Traction Control, Vehicle Dynamic Control, and so on) works on different vehicles.


This video shows Audi's EDL (Electronic Differential Lock) in action. Both left wheels are placed on the rollers, which simulate slippery surface (ice, mud). Both right wheels are on a dry surface. To get the car moving in these conditions, a front or rear differential lock is needed to transfer torque from left to right. This Audi has open (non-lockable) differentials front and rear, but EDL imitates a locking differential. The system must brake the wheel that spins (the left wheel) and transfer torque to the wheel with traction (the right wheel). However, as seen on the video, Audi's EDL is not as effective as a real mechanically locking differential. The system is not capable of bringing the spinning wheels to a full stop and transferring most of the torque to the right. If there was a real differential lock installed in either front or rear axle, the vehicle would have moved with little or no wheelspin. So EDL is a differential lock imitation.

Then, when wheel speed increases, the car finally takes off the rollers. EDL is defenetly a helpful traction device, but for on-road conditions only. If the vehicle was on a slope, it is doubtful EDL would make the vehicle move.


The next video shows the Volkswagen's EDL (Electronic Differential Lock) in action. This is a Volkswagen Bora/Jetta with Haldex Generation I automatic all wheel drive. On this model, the EDL is installed on the front wheels only. EDL helps some, but it is not a full replacement for a real differential lock.

Subaru Legacy Outback

This video shows a Subaru Legacy Outback 2.5 4AT VTD hill climbing with VDC off and VDC on. VDC is Subaru's electronic stability and traction control system that works on all four wheels. You can see that when VDC is turned on, the wheelspin is minimized.

Subaru Forester

The following video shows how VDC works on 2009 Forester 2.5XT. When wheels start spinning and it seems like the car won't move any further, do not release the throttle pedal. VDC will engage when excessive wheelspin is detected and brake the spinning wheel.

Subaru XV

The following video shows how Subaru XV all wheel drive and traction control system work.

Suzuki Grand Vitara, Mitsubishi Outlander XL, Toyota RAV4, Nissan X-Trail, Hyundai ix35

Suzuki Grand Vitara is much more capable off-road thanks to its very aggressive electronic differential lock imitation, which breaks the wheel to a full stop.

This is a Wiki, so feel free to correct any factual or grammatical error. Test here before posting.

There are 4 comments
Ron Thomas
August 16, 2015 - 19:03

Got a 97 Subaru Forester Legacy with 2.5L
It seems to stay in 4x4 drive making it difficult to turn into tight places. Put fuse in tow
circuit and now it drives fine and easier to turn. Any suggestion on fixing this issue. Checked entire front end and fluid levels. Replaced all axles,Ball joints,Ty=Rods (Inner and Outer} Checked rack in pinion run out. Not sure where to go from there..


December 23, 2013 - 03:43

Trully amazing!do all 2005 GV models have that sort of LSD?

December 31, 2008 - 04:30
This is great!

I have been looking for videos like this for years. Are you going to be adding more?
Where did you get the rollers? I'd like to try this with my car.

Reply to JonathanC
January 01, 2009 - 22:08
Re: This is great!

Hi, this is a video I found on youtube, it's not mine. I will be adding more of these soon.

Leave a Comment

? ?

Powered by TalkBack