Locking diffs how do they work?

[wildoliver]

Pretty much as title, I'm used to torsen and LSD plate type diffs as I've grown up around motorsport and built many cars over the years.

What I don't know yet is how the Audi diff locks work, my t.85 quattro has centre and rear diff locks, has anyone a diagram or explanation as to what happens when that button is pressed, especially within the diff itself.

[Error404]

pretty rudimentary - there is a vacuum diaphragm that actuates a lever to move a locking ring between the output flange shaft and the diff carrier.

[ranz]

It´s not audi, but basically audi has something similar to that:


Audi diffs: http://ranz.planet.ee/villu/torsenid.jpg (torsen, broken torsen and "kemppi" diff)
The right one was originally lockable audi diff, you see the toothed top on it and there is one moving part on the exit shaft, and when you push the lock button, it moves to that toothed part and locks the exit shafts.

[4WheelDrifter]

Unlocked.




Locked.

[wildoliver]

Fantastic thanks! Just what I needed!

[Jersey Paul]

This forum is superb.
Can you get a better answer?

[ranz]

Unlocked.

http://i90.photobucket.com/albums/k2...f-unlocked.jpg

Locked.

http://i90.photobucket.com/albums/k2...iff-locked.jpg

What cars diff is it? because as you can see from my pictures, S2 diff and V8 diff are not similar to that.

[4WheelDrifter]

What cars diff is it? because as you can see from my pictures, S2 diff and V8 diff are not similar to that.

The clue is in the name of this forum.

[terrybullwon]

The clue is in the name of this forum.

Play Nice Mr Drifter

[Le S2 Audi]

This forum is superb.
Can you get a better answer?

Always wondered this too....

But as it's well known on this forum I'm a numpty when it comes to mechanics...

[ranz]

The clue is in the name of this forum.

I don´t understand? it´s not S2 diff...

[4WheelDrifter]

I don´t understand? it´s not S2 diff...

It certainly is. From my original '91 AYV.

[ranz]

It certainly is. From my original '91 AYV.

That is interesting... because my own and my friends S2 (91year) cars have diffs what are on the picuture what I linked before.

The right one.

[4WheelDrifter]

@ Ranz. Looking at your picture the non-TorSen diff's drive gear is missing from the splines on the output.




You can see better in one of AndyP's pictures, with said gear in situ.




The ring is the part that moves to lock and unlock the rear diff. As described by Error404, and shown in my picture. The ring is moved by a pivoting wishbone that is connected to the vacuum actuator.

[s2driveruk]

i remember studying mine when i pulled it from the car with Pete (remember that? ) and was amazed at the simplicity of the solution for locking it