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Does the B9 RS4/RS5 still use the Crown Gear center differential?

Doesn't look like it in this diagram - RS4 is identical.

RS4John wrote: ↑

Sat Mar 27, 2021 9:11 pm

Doesn't look like it in this diagram - RS4 is identical.

How so?

This so:

RS4John ? What is the point your trying to convey in this image?
Do you believe you can see the internals of the centre diff in the image you have posted? (and now reposted)

Avantgarde wrote: ↑

Sat Mar 27, 2021 7:22 am

Does the B9 RS4/RS5 still use the Crown Gear center differential?

Almost certainly yes.
Crown gear in my 2018 car and I don't believe Audi would change Quattro system mid model (especially when there is no need to).
What else do you think it could be?

It just looks like a conventional prop-shaft centre coupling - agree with you I thought the B9s had full-fat Quattro - perhaps the illustration is incorrect?

Avantgarde
I don't know what you are really aiming at with your question. How else would you turn a rotating shaft through 90 degrees and transfer that much torgue at the same time?

I found this by doing a Google search
https://www.audi-technology-portal.de/e ... fferential.

It shows the sport diff and how it works, just remove the clever limited slip stuff for the standard one I guess. I can't guarantee as to the age of the info. If it is out of date I can think they will have only improved on it.

Jools

The Sport Diff is something else. In the original Quattro design there was a Torsen (Torque sensing) coupling in the centre of the car that could shift torque to whichever axle had the most grip - the original system was 100% mechanical, no electronics at all. The Sports Diff takes that one step further and shifts torque to whichever rear wheel has the most grip.

Over time Audi evolved the Quattro system so they could determine just how much torque was sent to the respective axles as a rear-wheel drive bias makes for a more driver orientated experience.

Audi have also taken the Quattro logo and applied it to drivetrains that don't have a centre coupling of any kind at all but rather use a Haldex (electro hydraulic clutch) ahead of the rear diff that is activated when the system senses that the front wheels are starting to rotate faster than the rears, in the latest F3 RSQ3 the Haldex can be activated as a setting in Drive Select too.

RS4John wrote: ↑

Sun Mar 28, 2021 8:35 pm

It just looks like a conventional prop-shaft centre coupling - agree with you I thought the B9s had full-fat Quattro - perhaps the illustration is incorrect?

B9 do have full fat Quattro. Your illustration looks OK but it doesn't show if the centre diff is crown wheel or of another type. In fact it barely shows the centre diff at all. Someone would need to remove the outer casing to determine the type.

Centre diff...was expecting something...well in the middle! Thanks. J

The center differential, be it Torsen or Crown Gear, is located where I’ve circled in the image below. My question is whether the B9 RS4 is a Torsen or a Crown Gear type. The B8 RS4 was a Crown Gear. I suspect that the B9 is back to Torsen. Hence my question from the original post, seeking information from those in the know.

Torsen (gen ?? forgot). fitted with zf8.

Nope, it should be Torsen C type.