2001 Citroen Relay 2.4L Diesel · ML51 BZX

A quarter-century-old panel van carrying the mechanical signature of age-related corrosion, this 2001 Citroen Relay passed its most recent MOT on 5 December 2025, though it carries an honest collection of advisories and one minor defect that together describe a chassis slowly succumbing to its environment. The pattern across recent tests is one of gradual deterioration rather than sudden failure, with corrosion-related advisories first appearing on 23 November 2023 alongside a major defect for an offside front service brake binding excessively, before the subsequent test on 24 November 2023 cleared the brake issue and left only the corrosion advisory. By the November 2024 examination the tester had noted subframe mounting corrosion on the offside front, radiator support corrosion, a non-excessive oil leak, a worn and pitted offside front brake disc, and inadequately secured under-bonnet wiring. The December 2025 test added age-related corrosion as a standing advisory, non-excessive transmission oil leak, perished sidewalls on both rear tyres, and a severely deteriorated nearside front outer CV gaiter, which was logged as a minor defect rather than a failure. The overall trajectory is stable in roadworthiness terms but trending towards increasing structural and component attention. Against a 25-year lifespan, the recorded 58,069 miles equates to approximately 2,323 miles annually, a notably low figure consistent with either light commercial use, long stationary periods, or intermittent deployment rather than sustained daily work. Mechanically, low annual accumulation on a vehicle of this vintage tends to favour the engine internals and transmission in terms of wear, but works against it where rubber components, brake discs, subframe fixings, and corrosion protection are concerned. Long periods of standing allow moisture to settle on ferrous surfaces, encourage under-bonnet condensation that affects wiring and connectors, and cause brake discs to pit and corrode from lack of regular sweeping action, all of which align precisely with the advisories on record. The lack of any large year-on-year mileage jumps in the visible test history suggests no sudden change in duty cycle, though the buyer should be alert to how the vehicle has actually been used between tests. For a prospective buyer, the live concerns on this Relay centre on the corrosion footprint already documented and the components that historically follow once chassis rust takes hold. The age-related and subframe mounting corrosion flagged at recent tests should prompt a close inspection of the offside front subframe leg, its captive bolts, and the surrounding floorpan, inner wings, and jacking points for any perforation or structural weakness that the MOT visual check would not necessarily have classified as excessive at this stage. The nearside front outer CV boot deterioration recorded in December 2025 is the next item to inspect; a torn gaiter will rapidly contaminate the joint with grease loss and road grit, so listen for a rhythmic clicking or CV knock when turning at full lock during a test drive, and inspect the boot itself for fresh grease flung onto the surrounding suspension. The offside front brake disc previously noted as pitted and scored, combined with the earlier binding service brake episode, warrants a cold start test drive to feel for any residual binding, judder under braking, or pulling to the nearside, and a check that the caliper slide pins and piston retract freely without the wheel becoming hot to the touch after a short drive. The transmission oil leak and the earlier general oil leak, both classed as not excessive, together with perished rear tyres and deteriorated under-bonnet wiring, complete the practical checklist. With the engine warm, inspect the transmission bell housing area and sump for fresh seepage or drips onto the subframe, since transmission fluid on a hot exhaust or subframe creates a long-term risk that the current not-excessive classification could easily tip into a future failure. Examine the rear tyres for cracking not only on the tread face but in the sidewalls and at the bead, and budget for replacement given that perished rubber is a common cause of MOT failure on older commercials. The insecure under-bonnet wiring advisory should be traced and properly clipped or rerouted, as chafed loom against a corroded rad support can develop into intermittent electrical faults that are difficult to diagnose. A final note on the binding brake history: confirm the handbrake holds firmly on an incline and that the offside front wheel spins freely by hand when jacked, as binding calipers on a 25-year-old Relay frequently return once the slider mechanism begins to seize, and this is one defect that has already escalated to a major failure on this vehicle's record.