2014 Mercedes-Benz CLS 2.1L Diesel · SL14 XDP

The most recent MOT, conducted on 18 February 2026, was a pass but returned three advisories – the off‑side rear tyre is close to the legal tread limit and has a nail embedded, the rear sub‑frame shows corrosion though not structurally compromised, and the same nail is noted again. Over the past twelve‑month period the vehicle moved from a failed result in December 2025 (with major faults on the parking brake, rear fog lamp and windscreen obstruction, plus a worn front brake disc) to a clean pass in November 2024 and a pass with only minor advisories in 2023 and 2022. The trend is therefore improving, having corrected the major safety items that caused the failure, but a number of lingering wear items remain and should be monitored closely. At 107,768 miles recorded for a 2014 model the average annual mileage works out at just under 9,000 miles per year, which sits comfortably within the normal UK usage envelope. There is no evidence of a sudden mileage surge that would suggest severe component fatigue, nor are there large gaps that would indicate prolonged periods of inactivity. Consequently the wear on high‑usage items such as the brake discs, pads and tyres is likely to be in line with the mileage rather than being accelerated by abnormal use. The recurring rear‑tyre nail must be removed and the tyre inspected for internal damage; a bulge or loss of air pressure on a test drive would point to a compromised carcass and would merit replacement. The rear sub‑frame corrosion, while not yet critical, should be examined for any thinning of metal at mounting points – any creaking or clunk when applying torque to the rear suspension could indicate progression toward a structural issue. The front brake disc was flagged as pitted and scored in the 2025 failure; if the disc is still near the minimum thickness it will need resurfacing or replacement, and you may notice brake pedal pulsation or a shudder under hard braking. The parking brake was recorded as inefficient, so verify that it holds the vehicle firmly on a hill and that the rear drum or caliper mechanism is not seized; a dragging sensation or uneven wear on the rear pads would be a warning sign. The rear fog lamp and windscreen obstruction are simple electrical and visibility items but should be rectified before the next test. Finally, the corroded brake pipe under the trays, noted in 2024, should be inspected for rust penetration and proper sealing – any loss of brake pedal firmness or a spongy feel could be symptomatic of a leak. Given the car’s age, beyond the specific MOT items you should check the condition of all tyres for side‑wall cracking or perishing, especially if they have been stored for long periods; tread depth should be well above the legal 1.6 mm limit and even wear across the tread surface is desirable. The 12‑volt battery, now twelve years old, may have diminished cranking power; a load test or a voltage check at idle and after a short run will reveal its health. Time‑based fluids – engine oil, coolant, brake fluid and power‑steering fluid – should be replaced if service stamps are missing or if the last change exceeds 24 months, as degradation can lead to corrosion, reduced braking efficiency and overheating. Inspect suspension bushes, ball joints and coil springs for any signs of looseness, leaking grease or excessive play, which would manifest as clunking over bumps. Finally, verify that the service book contains regular oil changes and any major service intervals (such as timing‑chain or transmission fluid) have been observed; a well‑documented history will give you confidence that the vehicle’s mechanical components have been cared for in line with its mileage and age.