2015 Audi A4 2.0L Diesel · ST64 SZO

The December 2025 MOT failure and subsequent pass at 137,198 miles reveals a deteriorating maintenance trajectory on this 2015 Audi A4. The initial failure centred on an excessively worn offside front suspension arm ball joint, a serious safety-critical defect that compromises steering geometry and wheel control. The same test flagged worn front and rear brake discs, light oil misting on the nearside rear shock absorber, and corrosion to the rear sub-frame. While the ball joint was evidently rectified for the immediate re-test, the concentration of faults across braking, suspension, and structural components points to escalating mechanical neglect rather than isolated wear. Mileage accumulation has been exceptionally steep. Between January 2024 and December 2025, the vehicle covered approximately 24,870 miles, pushing the total to 137,198 miles against an eleven-year average of roughly 12,473 miles annually. The January 2025 test at 124,328 miles already showed degraded front shock absorbers on both sides. Prior to that, a twelve-month gap separates the 2023 and 2024 records, with no MOT data visible for 2024, suggesting possible SORN status, missed testing, or incomplete records during a period of intensive use. The 2022 test at 99,797 miles was clean, indicating the subsequent three years introduced disproportionate wear. Recurring suspension faults demand particular scrutiny. The January 2025 test identified reduced damping effect on both front shock absorbers, and by December 2025 the nearside rear unit showed oil misting indicative of seal failure. The December 2025 offside front ball joint failure and the 2023 worn lower suspension arm bush on the same corner suggest concentrated stress or possible collision damage to that corner. A prospective purchaser should inspect all four damper units, verify ball joint and bush condition across the front axle, and check for alignment deviations or subtle chassis distortion. Brake and structural integrity concerns compound the assessment. Front and rear brake discs were flagged as worn, pitted and scored in December 2025, consistent with high-mileage use without timely replacement. The rear sub-frame corrosion, whilst judged not seriously weakened, indicates advancing rust in a structurally significant component exposed to road grime and salt over eleven winters. An in-person inspection should include pad and disc thickness measurements, caliper slide function, and detailed examination of sub-frame coating integrity and mounting point security. The oil level noted just above minimum at failure also raises questions about consumption rates and servicing regularity under sustained high-mileage operation.