2020 Audi S4 TDI Quattro Auto 3.0L Diesel · KN20 EBO

Structural corrosion of the rear suspension mountings is the primary mechanical concern in this vehicle's history, despite a generally stable roadworthiness trend. A failure on 14 March 2025 identified a seriously weakened offside rear coil spring mounting and corrosion on the nearside mounting, which were addressed to secure a pass on the same day. The vehicle has since remained clear of defects, concluding with a clean pass on 20 March 2026. The recorded mileage of 88,768 miles is high for a six-year-old vehicle, averaging roughly 14,795 miles per year. This usage pattern indicates a high-intensity operational life, which typically accelerates the wear of consumables and critical mechanical components. Prospective buyers should expect more advanced wear on suspension bushes, brake discs, and drivetrain linkages than would be found on a vehicle with average annual mileage. Inspection should focus on the rear suspension area to verify the quality of the repairs made to the coil spring mountings and to check for any further signs of corrosion on the subframe. During the test drive, pay close attention to any knocking or creaking sounds when traversing speed bumps or uneven road surfaces, as these can be symptoms of failing suspension components or lingering structural issues in the rear axle assembly. Previous advisories from April 2024 regarding cuts to the inner sidewalls of both front tyres suggest a history of alignment issues or impact damage. A thorough check of the current tyre wear is required to ensure the inner edges are not scrubbing, which would indicate a persistent tracking problem. Any steering pull or vibration felt at higher speeds during the test drive should be noted as a potential sign of ongoing alignment or suspension geometry faults.