Nobody has posted about this but as it's a known problem ant there is a TSB in various parts of the world about it I thought I'd post my experience. It may be better in another part of the site as it's relevant to all Quattro Ultra.

I drive briskly but not hard so I don't know how often the rear differential engages. I was waiting to turn right at traffic lights. a sharp 90 degree turn. Somebody waved me across so I had to go quickly with steering on full lock and the car juddered as if it was a worn clutch but coming from the rear. I booked the car in and discovered it only happened when I'd driven at least 6 miles and I was able to replicate the fault easily by pulling away reasonably quickly with steering on half to full lock.

So over a period of 10 weeks

Visit 1 Software update 1 day not fixed

Visit 2 Clutch adaptation (driving round in figures of eight while plugged into a laptop fixing the clutches in place) apparently to wear down any rough surfaces on the clutch pack. 3 days not fixed.

Visit 3 as above 6 days not fixed. They may have also  something with the propshaft coupling.

Visit 4 1 day not fixed. Took Master tech out to again demonstrate the fault. I made sure the car was warmed up and I didn't even need to live the car park to show him. I left the car with him.

Visit 5 5 days may be fixed but early days. I've been told to drive 200 miles for the transmission to adapt to my driving style. 

"The technician carried out an adaption drive on the clutch pack for the prop shaft and also changed the 4 wheel coupling oil"

So I'll let you know how I get on in a week or so but I'm glad I wasn't paying. I also had a puncture so I replaced both tyres on the same axle with the same tyres as the car came with so I avoided any complications with mismatched tyres.

 

 

Please let me know. I have the same thing in my brand new 2025 SQ5 with less than 1k miles.

Edited August 19, 2025Aug 19 by Magnet
Adding please

Afraid I can't help much. There are several different Quattros (3 that I know of) Torsen, Haldex and Ultra. Mine is Ultra but yours being an SQ5 has I believe the Torsen set up due to the vast torque being too much for Ultra. I had an almost new 2023 SQ5 for a while and never noticed that problem but it may turn out to be normal. 

If I'd specced air suspension I'd still have mine because I loved everything except the ride. Oh. and the sound activator on the bulkhead that I disconnected!

There are other Audis with the same transmission who's owners might be able to help but I can only suggest get on to the dealer.

Good luck.

 

Edited August 20, 2025Aug 20 by kevin8661

As an update on the fault with my car it seems the fluid change has so far cured the problem.

Does that mean it should be a service requirement along with DSG oil change? I don't know. My car had only done 27k miles.

Mine seems to only do it when its extremely hot outside. I don't know if its just the tires being sticky or what. But thanks for the reply. I'm new to Audi's, still trying to learn all I can about these. I still love it so far. She's been getting washed weekly and getting a Graphene Spray Coating weekly to protect it until my ceramic coating in October.