2015 Mercedes-Benz S-Class 3.0L Diesel · YB15 WGD

The vehicle’s most recent MOT history reveals a concerning inconsistency in testing, with a failed test on 2026-03-18 followed by a pass just five days later on 2026-03-23—both at the same mileage of 53,846. No defects were recorded in either instance, which suggests either an administrative oversight or a test centre error rather than genuine mechanical issues. The preceding MOTs, all passing without fail, indicate a stable pattern of compliance with roadworthiness standards over the past two years. However, the abrupt retesting at identical mileage warrants scrutiny, particularly if the vehicle has been stationary or used infrequently since. The recorded mileage of 53,846 miles over approximately 11 years equates to an average of around 4,895 miles annually, which is unusually low for a vehicle of this class and age. The gaps between tests—particularly the 13-month interval between the 2024 and 2025 MOTs—suggest prolonged periods of inactivity or very light use. Such low mileage can mask underlying issues, as components like suspension bushes, coil springs, and brake calipers may degrade passively over time without regular movement. The lack of advisories or defects in any test implies no immediate mechanical concerns were detected, but the static conditions could have allowed for subtle corrosion or seal degradation in areas like wheel bearings, exhaust mounts, or underbody panels. Given the clean MOT record, a buyer should prioritise a thorough inspection of high-wear items that may not have been stressed by low mileage. Focus on the suspension system—particularly the condition of rear coil springs and bushes, as these are prone to fatigue even with minimal use—and verify there is no binding or excessive play in the steering or rear brakes. Examine the brake discs and pads for uneven wear or corrosion, as static conditions can accelerate rusting. Underbody inspection is critical to check for corrosion on the subframe, exhaust system, and wheel arches, which may have developed despite the vehicle’s limited movement. The recent retesting also justifies a review of service records for oil changes, timing belt (if applicable), and fluid levels, as neglect in these areas could have gone unnoticed during MOT testing.