2015 Infiniti Q50 2.1L Diesel · RF15 KVL

The 2015 Infiniti Q50 presents a mixed mechanical picture. It passed its most recent MOT on 29 January 2026 at 110,443 miles, but the maintenance trend is clearly worsening. The tester flagged corrosion on both the front and rear sub-frames, noting the condition as not seriously weakened at that time. This is a new defect compared to the clean bills of health recorded in 2023 and 2021. The same sub-frame corrosion advisory first appeared in the January 2025 test at 100,583 miles, meaning the problem has persisted and been formally documented across two consecutive annual inspections. The vehicle remains roadworthy, but the emerging structural corrosion demands attention. The mileage record contains a significant anomaly. Between the January 2023 test at 77,871 miles and the January 2024 test at 146,067 miles, the odometer jumped by 68,196 miles in exactly one year. That is an extraordinary annual accumulation, far exceeding the typical 10,000 miles per year suggested by the vehicle's age. Such rapid accumulation implies sustained high-speed or long-distance driving, which accelerates wear on suspension bushes, brake discs, drivetrain mounts, and cooling components. The subsequent tests in 2025 and 2026 show the mileage stabilising around 100,000 to 110,000 miles, though the 2024 figure remains a clear outlier that warrants scrutiny for potential odometer tampering or a data entry error. Prospective buyers must inspect the sub-frame corrosion in person. Surface rust on structural components is common on older vehicles, but the tester's repeated flagging of both front and rear sub-frames suggests the corrosion is progressive. A thorough underbody examination is essential to verify whether the metal has thinned or weakened beyond advisory levels. Suspension mounting points, jacking points, and inner wing seams should also be checked for perforation or scaling. Given the mileage spike in 2024, the condition of consumable items like brake discs, pads, tyres, and suspension bushes should be assessed for accelerated wear. A pre-purchase inspection by a qualified technician, including a lift check of the underbody, is strongly recommended before committing to this vehicle.