2017 Audi A6 2.0L Diesel · K321 AAL

A pattern of advisory items rather than outright failures defines the roadworthiness profile of this 2017 Audi A6, with the most recent test on 27 May 2026 passing but flagging an offside rear brake pipe noted as corroded yet masked by grease or other material, alongside the standard caveat that engine covers and under-trays obscure certain components from inspection. Across seven recorded tests since 2020, the vehicle has never failed, but advisories have appeared in three of them, suggesting a gradual accrual of wear items rather than acute defects. The 2020 test flagged both front tyres worn close to the legal limit on their edges, the 2024 test recorded all tyres with low tread, and the 2026 test has now drawn attention to a brake pipe that is already showing surface degradation. The intervening years of clean passes do indicate that the vehicle has remained broadly serviceable throughout, though the re-emergence of chassis and consumable advisories at both ends of the testing window points to a car whose lower-order components are beginning to demand attention. With 52,527 miles recorded over nine years, this A6 is averaging roughly 5,800 miles annually, a figure that places it firmly in low-mileage territory for its age and mechanical specification. The testing history shows annual or biennial MOTs from 2020 onwards with no extended gaps, indicating the vehicle has remained in active use rather than laid up for significant periods, which reduces the likelihood of the kind of seized brakes, perished rubber, and stale fluid problems that can afflict long-stored cars. That said, low annual mileage on a vehicle of this type tends to concentrate wear on the components that do work during each journey, namely the front suspension, braking system, and tyres, which is consistent with the advisory pattern observed. The fact that brake pipe corrosion has now been noted at this mileage suggests that age-related environmental exposure, short journeys, and infrequent long runs may be combining to promote surface oxidation of the underbody metalwork. For a prospective buyer, the priorities on a physical inspection and test drive are dictated by the specific advisories on record. The offside rear brake pipe flagged as corroded in May 2026 is the most pressing concern, and it warrants a thorough examination of all underbody brake lines, particularly those running along the chassis rails and near the rear axle, looking for pitting, flaking, or blistering of the pipe coating. On the road, listen for any sponginess or excessive travel in the brake pedal, and under heavy braking check for any pulling to one side that could indicate uneven hydraulic pressure from a weakened or partially blocked pipe. The recurring tyre advisories across 2020 and 2024, including edge wear on both front tyres, should prompt close scrutiny of the wheel alignment, as uneven or feathering on the inner or outer edges of the current tread points toward worn suspension bushes or tired top mounts rather than simple rubber replacement. Given that the engine cover and under-trays were fitted at the most recent test and prevented full inspection of lower components, a pre-purchase evaluation should specifically request their removal so that oil leaks, corrosion on the subframe and engine mounting brackets, and the condition of the steering rack gaiters and drive shaft boots can be assessed directly. On the test drive, particular attention should be paid to any knocking or clonking from the front suspension over uneven roads, which is characteristic of worn control arm bushes and anti-roll bar linkages that are common wear items on A6 chassis of this vintage. Steering should feel precise without vagueness around the straight-ahead, and any clonking when turning at low speed could indicate worn drop links or tie bar bushes. Finally, with the 2026 advisory suggesting brake line corrosion is now active, it is prudent to budget for a professional brake pipe inspection and potential replacement of affected sections, as surface corrosion of this type tends to progress once initiated and would be an expected item on a nine-year-old vehicle regardless of its modest mileage.