2013 Mercedes-Benz CLS 2.1L Diesel · OU63 VPR

The most recent MOT test on 2026-07-15 resulted in a failure due to the offside rear upper shock absorber being insecurely attached, which is a critical structural integrity issue under DVSA standards. This failure contrasts sharply with the preceding three MOTs, which were all passed without defects, indicating a sudden and significant maintenance lapse. While the vehicle has not been retested since the failure, the presence of this major defect—particularly in a suspension component—suggests either a lack of proper servicing or a failure to address a previous issue that may have been overlooked. The advisory failures from previous years, particularly the corrosion on the brake pipes, further imply a pattern of deferred maintenance, which could exacerbate issues over time if not rectified promptly. The recorded mileage of 76,803 miles for a vehicle aged approximately 13 years represents an annual usage rate of around 5,908 miles, which is notably low for its age. Such low mileage can stem from either infrequent driving or prolonged periods of the vehicle being stationary, both of which introduce distinct wear and corrosion risks. If the vehicle has been left unused for extended periods, particularly in a damp or coastal environment, corrosion can accelerate in the brake systems, suspension components, and underbody areas. Conversely, if the mileage is genuinely low due to regular but light use, the wear on consumables like brake pads, tyres, and fluids may be more conservative. However, the combination of low mileage with a history of MOT advisories—particularly the corrosion advisories—suggests that the vehicle may have been subjected to conditions that promote rust and degradation, even if driving activity is minimal. Given the recent MOT failure and the recurring advisories, the prospective buyer should prioritise a thorough inspection of the suspension and brake systems. The insecure offside rear upper shock absorber is a red flag that requires immediate attention, as loose or failing suspension components can compromise steering stability, handling, and structural integrity. During a test drive, listen for unusual clunking or knocking noises from the rear suspension, particularly when cornering or over bumps, which may indicate further suspension bush or spring wear. Inspect the rear suspension for any signs of excessive play or misalignment, and verify that the shock absorbers are securely mounted to the vehicle’s frame and subframe. Additionally, the corroded brake pipes—both near and offside—pose a risk of brake fluid leakage, which could lead to reduced braking performance or even a complete loss of hydraulic pressure. Check for any fluid leaks around the brake lines, and ensure that the brake fluid level is consistent and that there are no unusual noises or vibrations during braking, which could signal binding calipers or warped discs. For the buyer’s immediate inspection, focus on the following areas: the brake system should be thoroughly examined for signs of corrosion on the discs, pads, and calipers, particularly if the vehicle has been stationary for extended periods. Binding calipers or discs can cause uneven wear, brake shudder, or a grinding noise when braking, which should be confirmed during a test drive. The tyre condition is critical, especially given the vehicle’s age and potential standing periods. Check for sidewall cracking or perishing, which can compromise tyre integrity and safety, even if the tread depth appears adequate. The 12V battery should be tested for voltage output when the engine is off and while the ignition is on, as prolonged inactivity can lead to sulphation or terminal corrosion. Fluid levels—particularly the engine oil, brake fluid, and coolant—should be checked for consistency and signs of degradation, as fluids can break down over time even with low mileage. Finally, verify that the service book or maintenance records are up to date, particularly for the timing belt, which in this case should have been replaced at around 100,000–120,000 miles or every 60 months, whichever comes first. If the vehicle has not been serviced in accordance with Mercedes-Benz’s recommendations, this is a significant risk, and the buyer should insist on a full pre-purchase inspection by a qualified mechanic to address the outstanding issues before proceeding.