2004 Jaguar XJ 3.6L Petrol · YJ53 AAD

The Jaguar XJ passed its most recent MOT test on 21 January 2026 with no major or dangerous defects recorded, although two advisories were noted concerning corrosion to both the front and rear sub-frames. While a pass is clearly a positive outcome, it should be viewed in the context of the immediately prior test on 8 January 2026, which resulted in a failure with three major defects relating to the parking brake system and a non-functioning nearside headlamp dipped beam. The presence of a failure so close to the pass suggests either that remedial work was carried out between the two tests or that the parking brake and lighting issues were borderline on the first attempt. Overall, the maintenance trend appears broadly stable rather than actively worsening, though the recurring advisories regarding sub-frame corrosion across consecutive tests indicate an ongoing deterioration that will require monitoring and eventual rectification. With 248,265 miles recorded over approximately 22 years of service, the vehicle has covered an average of around 11,285 miles annually, which is broadly typical for its age and not unusually high or low for a premium saloon of this era. There are no significant gaps in the recorded mileage progression that would suggest the car has been laid up for extended periods, nor are there any indicators of abnormally rapid accumulation. That said, the recorded mileage alone does not tell the complete story, as a high-reading XJ of this vintage will have experienced considerable wear to mechanical components such as the automatic transmission, suspension bushes, engine mounts, and interior trim. Prospective buyers should be aware that at this mileage level, consumables and major drivetrain components will have been replaced on multiple occasions, and verification of the service history to evidence these renewals is essential. Given the recurring parking brake defects, particular attention should be paid to the rear brake calipers, handbrake mechanism, and rear brake cables or actuators. The nearside parking brake inoperative on one side failure followed by a parking brake efficiency below requirements failure suggests either seized rear caliper mechanisms, stretched or seized handbrake cables, or excessive wear in the caliper handbrake mechanism. On a test drive, listen for any scraping or grinding noises from the rear brakes, check that the handbrake holds the vehicle firmly on an incline, and inspect the rear pads and discs for even wear. Additionally, the headlamp failure noted on the previous test should prompt a careful check of the nearside headlamp operation, including the dipped beam function, bulb condition, and any wiring or connector issues, as Jaguar headlamp assemblies of this era are known to suffer from condensation and connector corrosion. The persistent advisories concerning front and rear sub-frame corrosion are a more serious concern that warrants close physical inspection. Although the corrosion has not yet been categorised as seriously weakened, its recurrence across multiple tests indicates progressive deterioration, and on a Jaguar XJ of this age, sub-frame corrosion can advance rapidly due to the design and the exposure of structural components to road salt and moisture. The vehicle should be placed on a ramp for a thorough inspection of the sub-frames, suspension mounting points, and any structural members for signs of advanced corrosion, perforation, or repair. Furthermore, given the high mileage and age, a comprehensive assessment of the cooling system, including the radiator, water pump, and expansion tank, is advisable as Jaguar XJs of this generation are known for cooling system vulnerabilities, and verification of recent timing chain or auxiliary belt replacement along with confirmation of fluid services for the transmission, brake fluid, and coolant would provide additional confidence in the vehicle's mechanical condition.