2020 Audi S4 TDI Quattro Auto 3.0L Diesel · 72 DEB

A pattern of progressive brake wear advisories across consecutive MOT tests forms the defining mechanical theme of this Audi S4 TDI Quattro, supported by three straight pass certificates on the 2023, 2024, and 2025 tests. The most recent examination on 17 October 2025 flagged front brake discs as worn but not excessively, alongside wearing thin front and rear brake pads. This follows a 2024 advisory noting rear brake pad wear, indicating that friction material is steadily approaching the replacement threshold and that the discs are now also showing measurable wear. The braking system's trajectory suggests a vehicle that is approaching a brake service cycle, with pad replacement now overdue or imminent depending on driving style and route profile. There are no recorded structural corrosion advisories, suspension component failures, exhaust integrity issues, or lighting defects across the three tests, and the lone 2023 emission advisory reflects a diagnostic sampling issue rather than a tailpipe compliance failure. Annual mileage accumulation of roughly 14,100 miles places this car well above the average for a 2020-plate vehicle of its age, signalling consistent and reasonably heavy use rather than periods of standing or seasonal-only running. The MOT cadence is annual without any recorded gaps, meaning the vehicle has been actively maintained on the road throughout its life, and mileage progression between tests has been smooth and continuous. Mechanically, sustained higher mileage on a quattro diesel of this type concentrates wear on drivetrain, suspension, and braking components rather than on corrosion-prone areas, and this is consistent with the advisory profile showing brake wear but no structural or underbody advisories. The diesel powertrain and automatic transmission will have logged substantial real-world use, so drivetrain fluids, transfer box and rear differential oil, and dual-mass flywheel condition warrant closer attention than the MOT record alone can confirm. A prospective buyer should prioritise a thorough brake inspection beyond what the advisories convey, as the combined front disc wear and thin pads on both axles indicate a full brake refurbishment is now likely required. On a test drive, listen for any binding caliper symptoms such as a persistent dragging sensation, uneven pedal feel, or pulling to one side under braking, and inspect the discs for lipping, hot spots, or surface scoring. Given the mileage and the quattro drivetrain, pay particular attention to suspension bushes, anti-roll bar drop links, and control arm wear, listening for clonks or knocks over uneven surfaces and feeling for vagueness or wandering in the steering. Road test under load for any signs of turbo lag, transmission hesitation, or unusual vibration through the drivetrain, and verify that all quattro system fluids, including transfer box and rear differential oil, have been serviced to schedule. Finally, request evidence of recent cambelt or timing chain inspection history specific to the 3.0 TDI engine, as these components are critical service items on high-mileage diesel units regardless of MOT outcome.