1990 Jaguar XJS 5.3L Petrol · G414 DVC

A consistent thread running through the MOT history of this 36-year-old Jaguar XJS is progressive structural and underbody corrosion, with corrosion-related advisories appearing in every test from 2018 onwards. The most recent test on 2025-11-28 was a pass, but the accompanying advisory list again flagged a corroded lower radiator mount, corroded rear coil springs at all four locations, and a minor exhaust gas leak. Earlier tests traced an expanding pattern: the 2018 entry first raised rear subframe corrosion and corroded brake pipes, the 2023 test escalated the rear suspension picture with corroded fuel pipes and corroded rear spring mountings on both sides, and the 2024 test added underseal-covered rear suspension mounting repairs. Across seven recorded tests there has been no outright failure, but the advisories describe a steady accumulation of age-related underbody deterioration rather than a stable or improving trend. The recorded mileage of 134,378 miles over 36 years equates to an average annual accumulation of roughly 3,733 miles, which is low for a vehicle of this age. Testing history begins in 2018, leaving the first 28 years of the car's life undocumented in MOT terms, and the gap between the earliest recorded mileages and the most recent cannot be precisely verified from the available data. Low annual mileage of this nature on an XJS typically reflects periods of limited use or extended standing rather than continuous light driving, and the mechanical consequences are visible in the record itself: oil leaks were noted in both 2022 and 2021, wheel bearing play has appeared on multiple occasions, and corroded fuel pipes near the tank have been flagged in three consecutive tests from 2020 to 2023. A prospective buyer should prioritise a physical inspection of every underbody component referenced in the advisories. With the rear subframe first flagged in 2018 and rear spring mountings repeatedly noted as corroded or repaired, the car should be raised on a ramp to check the rear subframe rails, spring seats, shock absorber mounts, and trailing arm bushes for any perforation or distortion that has moved beyond surface corrosion. The brake pipes, which were flagged as corroded in 2018, need close examination along their full length, particularly at unions and bends, because brake line corrosion on a chassis of this age can progress between tests. Front wheel bearings were noted with slight play on both sides in 2024, so a test drive should include steady cornering on a smooth road to listen for any hum or drone that would indicate the play has worsened, and the fronts should be rocked with the wheel raised to confirm bearing condition. On the road, attention should be paid to suspension behaviour over uneven surfaces, as corroded rear coil springs can lead to sharp knocks, sagging ride height, or audible creaks from the rear when traversing speed bumps. The oil leak advisories from 2021 and 2022 warrant a check for fresh oil residue on the sump, rocker cover, and gearbox bellhousing during inspection. The exhaust leak flagged in 2025 should be located precisely, listening for ticking under acceleration or a change in engine note, as exhaust gases entering the engine bay or cabin area is a safety concern. Finally, fuel smell at the rear of the vehicle would suggest the corroded rear fuel pipes noted since 2020 have deteriorated further, and any strong petrol odour should prompt immediate withdrawal from purchase until the lines are professionally inspected.