2014 Mercedes-Benz C 2.1L Diesel · WM63 RYH

The latest MOT test in September 2025 resulted in a pass, continuing a trend of compliance since the previous year’s failure was rectified. The overall maintenance picture shows a mixed but manageable trajectory, with the 2024 failure addressing deteriorating anti-roll bar linkage ball joint dust covers—a recurring theme that first appeared as a minor advisory in 2023. The persistent oil leak advisory, noted in every test since 2023, suggests a long-standing but non-critical seepage, likely from a deteriorating gasket or seal. While the vehicle has not suffered structural or safety-critical failures, the pattern indicates that suspension and fluid integrity require close attention. At 113,834 miles over 12 years, the annual average of roughly 9,500 miles aligns with typical usage for a vehicle of this age, neither excessively low nor high. This mileage suggests moderate wear on consumables such as brakes, suspension bushes, and drivetrain components, but not the extreme fatigue seen in high-mileage examples. There are no indications of prolonged inactivity, which reduces the risk of standing-related issues like seized calipers or corroded brake discs, though age-related degradation of rubber and fluid systems remains a consideration. The recurring oil leak advisory warrants a thorough inspection of the engine bay, particularly around the valve cover gasket, sump, and oil cooler seals, as these are common sources on this model. Look for fresh oil deposits on the underside of the engine and check the dipstick for signs of overfilling or metallic particles. The anti-roll bar linkage ball joints, previously flagged for deteriorated dust covers, should be examined for play or binding, as compromised seals accelerate wear and can lead to clunking noises over rough surfaces or uneven tyre wear. On the test drive, listen for knocks from the front suspension when cornering or braking, which could indicate worn joints or bushes. Given the vehicle’s age, also assess the condition of the tyres for sidewall cracking or perishing, as rubber degrades over time regardless of mileage. Verify the 12V battery health, as original units often require replacement after 5-7 years, and check for corrosion on brake discs or binding calipers, which can occur even with regular use. Finally, confirm the service history aligns with the mileage, paying particular attention to timely oil changes and fluid replacements, as the persistent oil leak may have been masked by infrequent servicing. A pre-purchase inspection focusing on these areas will provide clarity on the extent of any underlying wear.