WARNING: This page is about a different car, the 2023 Audi SQ8, 2023 Audi RS Q8, and 2023 Audi Q8. However, it is still accessible from the selected car via links, so may be relevant.
-- Check the torque converter hub -arrow- for wear grooves.
Fig 1: Checking Torque Converter
Courtesy of AUDI
The torque converter must be replaced if it is damaged or faulty.