1994 Mercedes-Benz 609 D 4.0L Diesel · L78 MWJ

The vehicle presents a stable roadworthiness profile following a period of significant mechanical and structural concern. The most recent MOT on 11 June 2026 at 208,136 miles shows a clean pass, with the tester noting the underside is covered in underseal. This indicates a proactive approach to corrosion management, which is essential for a vehicle of this age. The maintenance trend has improved significantly since the mid-2010s, moving from a history of frequent failures and advisories to several consecutive years of defect-free results between 2017 and 2025. The mileage accumulation is consistent with a vehicle of this age, averaging approximately 6,500 miles per year. The record shows a notable period of lower usage between 2019 and 2024, where the mileage only increased from 200,051 to 206,170. This suggests the vehicle may have been used for seasonal or intermittent trips rather than heavy daily commuting. The recent jump of roughly 2,000 miles between the 2025 and 2026 tests indicates a return to more regular usage. A prospective buyer should focus their physical inspection on the structural integrity and the braking system. While the 2026 record mentions underseal, the history shows a recurring pattern of corrosion in brake pipes, hoses, and power steering lines, particularly between 2005 and 2016. The 2007 failure for a chassis crack near the body mountings and the 2005 report of body displacement relative to the chassis are serious historical issues that warrant a close inspection of the mounting points and frame. The steering and exhaust systems also require scrutiny. The drag link ball joints and exhaust mounting issues appeared frequently in tests between 2008 and 2016. Although these issues seem to have been resolved given the clean passes in recent years, the mechanical components should be checked for play or leaks. The recent clean history is encouraging, but the long-term reliability of a 32-year-old diesel engine and its supporting chassis remains the primary technical consideration.