2003 Mitsubishi Shogun 3.5L Petrol · WM03 BYB

A serious structural corrosion concern dominates the early MOT history of this 23-year-old Mitsubishi Shogun. In April 2019 the vehicle was issued a failed test with two dangerous defects, both flagging that the nearside and offside rear suspension component mounting prescribed areas on the inner sills were corroded to the extent that control of the vehicle was likely to be adversely affected. The same test also recorded major defects for both rear seat belt anchorages on the inner sills showing significantly reduced strength or continuity. That combination of dangerous suspension mount corrosion and compromised seat belt anchorage integrity on the same structural member is a red flag for any prospective buyer, even though the car passed its next recorded test in 2020 with no defects noted and has since passed each subsequent annual examination, including September 2022 when advisories were raised for a non-excessive rear differential oil leak, light oil misting on the offside front shock absorber, and corrosion within 30cm of a mounting on the offside integral body structure. The trajectory of advisories suggests progressive structural surface corrosion that has not yet reached dangerous proportions but is clearly present on a ladder-chassis vehicle now over two decades old, and the jump from a clean 2020 and 2021 pass to multiple advisories by 2022 indicates this deterioration is still ongoing rather than arrested. The usage profile is broadly typical for the vehicle's age, with 142,534 recorded miles accumulated over roughly 23 years at an average of around 6,200 miles per year, so neither long-term storage nor exceptionally heavy use is evident in the mileage curve. The testing cadence shows a regular annual pattern from 2017 through 2022 with no multi-year gaps, which means there are no extended periods off the road that would raise concerns about seized brakes, perished fuel lines, or deteriorated coolant hoses from standing. The 2019 test entries are particularly significant because they confirm the vehicle was in active use at that time, yet the inner sill condition had already deteriorated to dangerous and major failure levels, indicating that the structural corrosion progressed under normal operating conditions rather than as a consequence of neglect during storage. A buyer should treat the inner sill rear suspension mounting areas and the rear seat belt anchorage zones as priority inspection points, because while these areas passed in 2020, there is no recorded evidence in the MOT history of any remedial welding, section repair, or structural intervention between the 2019 failure and the subsequent passes. On examination, press firmly on the lower sill panels behind the rear wheels and look for any signs of aftermarket plating, fresh paint, filler, or underseal applied over corrosion, as MOT testers will pass surface corrosion that does not seriously affect security even where the underlying metal is thinning. Pay close attention to the offside front shock absorber for any worsening of the oil misting noted in 2022, checking for a damp residue on the lower body of the unit and listening for a dull thud rather than a crisp rebound over speed bumps. The rear differential oil leak should be inspected from below for active dripping onto the underbody or rear cover, and the front brake pads flagged as wearing thin back in 2017 should be physically inspected for remaining friction material thickness, as they will have covered around 70,000 miles since that advisory was issued. On a test drive, listen and feel specifically for any clonking or knocking from the rear suspension over uneven surfaces, which would suggest the mounting areas flagged in 2019 have deteriorated further despite the subsequent passes, and check for any lateral wander or instability under braking that could indicate compromised structural rigidity around the inner sills. Examine the front brake pedal for judder under firm application, which on a vehicle of this age and mileage would suggest warped front discs rather than pad wear alone. Finally, inspect the exhaust system from the manifold rearwards for blue smoke on overrun indicative of turbo seal wear or valve guide issues common to diesel Shoguns of this era, and verify that all rear seat belts anchor firmly to the body without any lateral play, as the 2019 record demonstrates this is a known weakness point on this particular chassis that warrants direct verification rather than assumption.