2021 Mercedes-Benz G 400 AMG Line Prem D 4MATIC A 2.9L Diesel · 48 HJ

A clean, unbroken MOT record across three successive tests positions this G 400 as a strong roadworthiness candidate, with the most recent pass on 13 March 2026 confirming no defects at the point of test. The earlier entries from 7 February 2025 and 6 March 2024 likewise returned clean sheets, suggesting the vehicle has consistently met minimum statutory requirements without the need for advisory commentary on wear items. The absence of any advisories on a vehicle of this age and specification is notable, as even lightly used premium SUVs typically generate some monitoring notes on tyres, brakes, or underbody components within their first MOT cycle. For a buyer, this pattern points towards either genuine mechanical integrity or a history of pre-test rectification, and it underscores the importance of a physical inspection to verify that the absence of advisories reflects underlying condition rather than recent preparation. The odometer reads 12,223 miles against an age of approximately five years, equating to an annual accumulation of around 2,445 miles, which is markedly below the typical mileage profile for a luxury off-roader. Such a low trajectory is consistent with a second-car role, weekend use, or extended periods of storage, and it warrants specific mechanical scrutiny rather than reassurance. Long static intervals can accelerate degradation of certain components, particularly the 12V battery, brake discs and callipers from corrosion due to infrequent use, and the various rubber seals and flexible boots across the driveline. Conversely, the powertrain, clutch, and major wear surfaces will have seen minimal cumulative load, which is generally favourable for longevity of the OM656 diesel engine and nine-speed automatic transmission. Any gaps between test entries appear proportionate and there is no evidence of odometer discontinuity, though confirmation of stored mileage should form part of any pre-purchase due diligence. From a buyer inspection standpoint, the lack of flagged components means attention must focus on items that may not yet have reached advisory thresholds but are nonetheless relevant given the usage profile. On a test drive, listen for any clonks or knocks from the front suspension over uneven surfaces, as the double-wishbone arrangement on the G-Class can develop play in the lower control arm bushings and anti-roll bar links over time. Check for any pulling under braking or uneven pedal feel, as low-mileage brake discs are prone to surface corrosion that may not have been recorded as an advisory but can still manifest as pedal judder. Inspect the underside carefully for any signs of fluid seepage from the diesel fuel system, AdBlue injector, or front and rear differential units, all of which would warrant mechanical investigation before purchase. Tyres should be examined for age-related cracking as well as tread depth, given that low-mileage vehicles often retain original fitments beyond their recommended service life despite showing ample tread. The G-Class is a complex vehicle with extensive electronics, air suspension components on related variants, and a sophisticated 4MATIC transfer case system that should be evaluated functionally rather than purely visually. Confirm that the low-range transfer case engages smoothly, that any ride-height adjustment operates without hesitation or warning messages, and that the centre console displays show no stored fault codes requiring diagnostic clearing. Verify that the diesel particulate filter has not triggered any recent regeneration failures and that the AdBlue system is functioning within its normal operating range, as these are common cost-of-ownership concerns on modern Mercedes diesel applications. A pre-purchase inspection by a specialist familiar with the G-Class platform, combined with a full HPI provenance check, would be a prudent complement to the clean MOT history presented here. Overall, the documented test record supports confidence in the vehicle, provided that the mechanical and electronic systems are independently validated to confirm the absence of advisories reflects true condition rather than recent rectification ahead of test.