2007 Citroen C4 2.0L Diesel · GL57 WDZ

The defining mechanical story of this 2007 Citroen C4 is one of front-end wear and a single but significant safety failure, with the most recent test on 2022-03-07 resulting in a pass but carrying forward the registration plate lamp defect that had appeared a week earlier. The headline event in the recorded history is the 2022-02-28 failure, where the front inner brake discs on both sides were classified as dangerously weakened, accompanied by an advisory that the front brake pads were wearing thin across both sides. This sits alongside a recurring pattern of constant velocity boot deterioration on the drive shafts, flagged in both 2019 and 2021, and a 2018 advisory for pitted front brake discs. The overall trajectory is therefore one of a vehicle that has accumulated wear on its braking and drivetrain hardware, with the discs deteriorating from an advisory condition in 2018 to a dangerous level by early 2022, indicating that interim replacement may not have been carried out or that wear accelerated in the final period of testing. Against a 19-year age span, the recorded mileage of 126,559 miles averages out to approximately 6,661 miles per year, which is broadly typical for a car of this vintage. However, the testing history is notably thin and uneven, with a substantial gap between the 2017-10-30 test and the 2019-11-27 test, and a further gap before the 2022 entries. Such intervals can mask intermediate deterioration, and the absence of recorded tests between 2010 and 2015 in the visible data means the full mechanical history cannot be reconstructed. The jump from a clean 2017 pass to brake disc and CV boot advisories by 2018, followed by worsening through 2019 and 2021, suggests progressive wear consistent with regular road use rather than prolonged standing. For a prospective buyer, the front braking system should be the primary area of physical inspection, as the record documents a clear progression from pitted discs in 2018 to dangerously weakened inner discs by early 2022. On a test drive, listen for any grinding or scraping from the front wheels, check for pulsation through the brake pedal under firm application, and inspect the discs visually for deep lipping, blueing, or cracking around the inner circumference. The constant velocity boot defects on both sides, first noted on the nearside front in 2019 and then both sides in 2021, are a known weak point on C4s of this era; with the car now over four years past that 2021 advisory, the boots will require close examination for splits, grease loss around the joint, and any clicking or vibration under sharp steering lock that would indicate a failing joint rather than just perished rubber. Beyond the documented items, the age of the vehicle and the lack of recent MOT data mean that a thorough pre-purchase inspection should pay particular attention to areas not covered by the visible test record, including the rear brake components, suspension bushes and coil springs, exhaust integrity, and any structural corrosion around the subframe and wheel arches. On the road, the C4 is known for its hydropneumatic suspension, so any sagging at the rear, slow self-levelling on startup, or uneven ride height warrants immediate investigation. Under the bonnet, check for oil leaks from the cam cover and sump, condition of the timing belt if it has not been replaced, and ensure the engine management warning light does not illuminate, given the 2022 MIL-inoperative failure. Finally, verify whether the dangerous brake disc defect and the MIL issue were professionally rectified between the February 2022 failure and the March 2022 pass, as the rapid retest suggests remedial work was carried out but its quality and longevity deserve direct confirmation.