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

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

Post by Avantgarde » Sat Mar 27, 2021 7:22 am

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

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RS4John
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS4John » Sat Mar 27, 2021 9:11 pm

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

Image
2020 F3 RSQ3 Std, 400PS, Daytona Grey/black Ara blue interior, Pano, C&S pack, Red calipers, HBA, TP monitoring, 5yr Warranty, Cete AVC, EBC Redstuffs
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Avantgarde
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by Avantgarde » Sun Mar 28, 2021 9:38 am

RS4John wrote:
Sat Mar 27, 2021 9:11 pm
Doesn't look like it in this diagram - RS4 is identical.

Image
How so?

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RS4John
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS4John » Sun Mar 28, 2021 6:21 pm

This so:
Image
2020 F3 RSQ3 Std, 400PS, Daytona Grey/black Ara blue interior, Pano, C&S pack, Red calipers, HBA, TP monitoring, 5yr Warranty, Cete AVC, EBC Redstuffs
Gone, 2016 8U RSQ3 Performance
Gone, 2018 B9 RS4
Gone, 2015 8U RSQ3

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RS Owner
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS Owner » Sun Mar 28, 2021 6:27 pm

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)
Current : 2018 F5 RS5 (Let's Fire Up the Quattro)
Gone : 2017 M3 CP
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS Owner » Sun Mar 28, 2021 6:38 pm

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?
Current : 2018 F5 RS5 (Let's Fire Up the Quattro)
Gone : 2017 M3 CP
Gone : 2007 B7 RS4 ( :kissmyrings: )

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RS4John
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS4John » 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?
2020 F3 RSQ3 Std, 400PS, Daytona Grey/black Ara blue interior, Pano, C&S pack, Red calipers, HBA, TP monitoring, 5yr Warranty, Cete AVC, EBC Redstuffs
Gone, 2016 8U RSQ3 Performance
Gone, 2018 B9 RS4
Gone, 2015 8U RSQ3

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

Post by Jools » Sun Mar 28, 2021 9:40 pm

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

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RS4John
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS4John » Sun Mar 28, 2021 10:26 pm

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.
2020 F3 RSQ3 Std, 400PS, Daytona Grey/black Ara blue interior, Pano, C&S pack, Red calipers, HBA, TP monitoring, 5yr Warranty, Cete AVC, EBC Redstuffs
Gone, 2016 8U RSQ3 Performance
Gone, 2018 B9 RS4
Gone, 2015 8U RSQ3

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

Post by RS Owner » Sun Mar 28, 2021 11:02 pm

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.
Last edited by RS Owner on Sun Mar 28, 2021 11:33 pm, edited 1 time in total.
Current : 2018 F5 RS5 (Let's Fire Up the Quattro)
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RS4John
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Re: Does the B9 RS4/RS5 still use the Crown Gear center differential?

Post by RS4John » Sun Mar 28, 2021 11:33 pm

Centre diff...was expecting something...well in the middle! Thanks. J
2020 F3 RSQ3 Std, 400PS, Daytona Grey/black Ara blue interior, Pano, C&S pack, Red calipers, HBA, TP monitoring, 5yr Warranty, Cete AVC, EBC Redstuffs
Gone, 2016 8U RSQ3 Performance
Gone, 2018 B9 RS4
Gone, 2015 8U RSQ3

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

Post by Avantgarde » Mon Mar 29, 2021 1:19 am

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.
Image
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AD3FC129-28BA-450F-B5B5-D7FC37FE972B.jpeg

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

Post by diuleiloumou » Thu Mar 31, 2022 4:00 am

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

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

Post by diuleiloumou » Wed Apr 06, 2022 1:46 pm

Nope, it should be Torsen C type.

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