Known Issue: Quattro Ultra Vibrations or Binding in Tight Turns
TSB 2059057 Fluid Part Number G 055 515 A2

Quattro Ultra all-wheel drive systems are starting to show a common issue — vibrations or binding during tight turns.
One of the big culprits? The AWD clutch fluid. And of course, Audi never recommends changing it (shocking, right?).
We strongly suggest replacing this fluid when your S-Tronic or automatic transmission service is due — usually every 30,000 to 40,000 miles.
This 2018 Audi A4 Allroad came in with 115,000 miles — and had never had the AWD clutch fluid changed. We just did it for the first time, and the fluid was filthy. No surprise this system was starting to act up.
If your Audi has the Quattro Ultra system, don’t wait until it starts binding — be proactive and service it before it becomes a major issue.
Here is a copy of the TSB that can be found on the NHTSA website:
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