2012 Mercedes-Benz G-Class 3.0L Diesel · NA04 ADA

The most recent DVSA examination on 15 January 2026 resulted in a pass, although five advisories were issued, the most notable being a brake pipe at the nearside front that was recorded as corroded and covered in grease or other material after the flexible section leading into the caliper. A prior test attempt on 12 January 2026 failed on a major defect for an inoperative nearside front position lamp, alongside the same four tyre protrusion advisories that appeared on the subsequent pass. Reviewing the trajectory across the recorded tests, there is a discernible downward trend in maintenance condition. The 2022 test recorded no advisories, but from 2023 onwards, brake disc wear, pad wear, an oil leak, deteriorated position lamp output, and tyre wear advisories began accumulating, culminating in the 2026 advisories covering all four tyres protruding beyond the wheel arches and the now flagged brake pipe corrosion. This pattern suggests a vehicle that has been less rigorously attended to in recent years, with several issues either persisting unresolved or developing into more serious concerns. With a recorded mileage of 48,090 miles over approximately 14 years, the G-Class averages around 3,435 miles annually, which is substantially below typical usage for a vehicle of this type and age. Such low annual mileage raises the prospect of extended standing periods, which can produce their own characteristic mechanical issues distinct from those caused by wear through use. It is worth scrutinising the MOT records for any gaps or unusually low increments between tests, as large standing periods can accelerate corrosion on ferrous components, allow brake discs to develop surface rust and potentially cause calipers to bind, and degrade rubber and fluid components through age rather than mileage. Given the advisory history, particular attention should be paid to the braking system during a physical inspection and test drive. The recurring brake disc wear advisories from 2023 onwards, particularly the pitted and scored inner faces noted on the rear discs in 2024, warrant a close examination of disc thickness and run-out, as uneven disc wear can cause brake shudder under deceleration. The flagged brake pipe corrosion at the nearside front is a more pressing concern; this type of advisory often indicates the flexible hose or its metal union is compromised by corrosion, and failure of such a component under hydraulic pressure would result in a total loss of braking on that corner. On a test drive, listen for any clonking or knocking from the front suspension, feel for pulling under braking which might indicate a binding caliper, and check for any warning lights related to the braking system. The oil leak advisory from 2024 should also be revisited; inspecting the underside for fresh oil residue around the engine sump, front crank seal, or oil filter housing will help determine whether this has progressed. Beyond the recorded defects, the combination of low mileage and 14 years of age introduces several age-related concerns that may not be captured in the MOT record. Tyre sidewalls should be examined closely for perishing and cracking, particularly on the G-Class given the heavy nature of the vehicle and the load placed on sidewalls during cornering, and note that all four tyres were flagged for protruding beyond the wheel arches in 2026, which may indicate non-standard wheel and tyre combinations or suspension geometry issues. The 12-volt battery should be load-tested, as a battery that has been subjected to frequent short trips and long standing periods is prone to sulphation and premature failure. Brake calipers that have been sitting can develop piston seizure, so confirm the vehicle rolls freely on a flat surface and that each wheel rotates without resistance when jacked. Finally, verify the timing of fluid services; brake fluid, coolant, transmission fluid, and differential oils degrade through age and require replacement on a calendar basis rather than purely by mileage, so a comprehensive service history documenting these renewals is essential for confidence in the vehicle's mechanical integrity.