2016 Mercedes-Benz CLA 2.1L Diesel · FG66 OFU

A fractured rear coil spring recorded as a Major defect at the September 2025 test is the standout mechanical event in this CLA's recent history, and it sets the tone for any prospective evaluation. Although the vehicle subsequently passed on 26 September 2025 with no defects recorded, the fact that a coil spring failed during inspection at this age and mileage warrants close attention. Coil springs do not simply snap without prior fatigue; corrosion, extended static loading, or sustained low‑mileage use can all accelerate metal fatigue, and on a Mercedes‑BENZ of this generation the rear springs sit within a multi‑link suspension assembly where a fractured spring can also distress neighbouring components such as the shock absorber, control arms and subframe mounting points. The 2023 failure, which involved a deep tyre cut exposing ply and an incorrectly coloured rear direction indicator, is a more isolated event and the subsequent clean pass in 2024 suggests those issues were rectified promptly. With 51,473 miles spread across roughly ten years, this CLA has averaged only around 5,147 miles annually, which is well below typical mileage for a vehicle of this age. Such low annual accumulation suggests periods of light use or extended standing, both of which carry specific mechanical consequences. Brake discs and pads can suffer from surface corrosion during prolonged inactivity, even where pad material remains serviceable, and low usage tends to produce glazed pad surfaces that lose initial bite until they are thoroughly re‑bedded. Rubber components throughout the chassis, including the fractured spring itself, can also deteriorate faster in vehicles that sit for long periods, particularly when stored outdoors, as the constant compression of springs and bushes without the damping effect of regular driving accelerates material fatigue. Given the rear coil spring failure, a test drive should concentrate on the rear suspension behaviour. Listen for clonking or knocking noises from the rear over speed humps, uneven road surfaces and driveway entries, and pay particular attention to any sense of the rear settling unevenly when stationary on level ground. A fractured spring typically produces a slightly lower ride height on the affected side, so visually compare the rear wheel arch gaps from nose‑on and from the rear. Steering feel should also be evaluated, as any compromised rear spring can allow the axle to shift slightly under load, producing a vague or wandering sensation at motorway speeds. Inspect the inner wing, suspension turrets and spring seats for any evidence of surface corrosion that might have contributed to the failure, and verify that the replacement spring fitted prior to the September 2025 pass is from a reputable source. The pattern of advisories around the tyres and rear brake pads is also worth pursuing. The 2024 and 2025 tests both flagged rear brake pads as wearing thin, which on a low‑mileage car indicates either infrequent brake use allowing the pads to corrode unevenly, or genuine wear from occasional heavier stops. On the test drive, expect the first few brake applications to feel slightly grabbing or uneven as any surface corrosion is scrubbed away, and listen for any binding or grinding from the rear calipers. The tyre‑related advisories covering sidewall damage, perishing and a deep cut to the ply in 2023 suggest the wheels and tyres have at some point come into contact with kerbs or debris. Check all four sidewalls carefully for bulges, cracks and repaired punctures, and confirm the sidewall construction is undamaged, as Mercedes‑BENZ low‑profile tyres on the CLA have limited sidewall flexibility and any prior impact damage can develop into slow leaks over time.