2018 Mazda 3 2.2L Diesel · DN18 TYZ

The defining mechanical story of this 2018 Mazda 3 is one of clean and consistent roadworthiness rather than a pattern of failures. Across six recorded MOT tests spanning 2021 through February 2026, the vehicle has passed every examination without a single advisory related to corrosion, suspension, braking system integrity, exhaust, or structural components. The only flagged items over an eight-year history are a small cluster of tyre wear advisories and a minor oil leak, all of which were recorded as advisories rather than failures. The most recent test on 2026-02-20 was a clean pass with no defects recorded, reinforcing a stable and improving trend in the latter portion of the record. The front tyres which were flagged in 2024 do not appear as a recurring issue in the 2025 or 2026 results, suggesting they were addressed. With 99,778 miles recorded against an age of approximately eight years, this vehicle has accumulated around 12,472 miles annually, which is a notably high usage rate for a car of this vintage. There are no unusual gaps in the testing history, with annual tests consistently recorded from 2021 onwards, and the mileage progression between tests appears steady and proportionate. This level of sustained road use means that consumable wear items such as brake pads, discs, tyres, and suspension components will have been working consistently hard, and the absence of any brake-related advisories on the most recent two tests suggests those components are currently in serviceable condition. However, the higher-than-average mileage places greater demand on the entire drivetrain, so items that the MOT does not directly cover, such as the clutch, gearbox internals, and engine ancillaries, deserve proportionate attention. For a prospective buyer, the minor oil leak advisory from February 2024 is the most specific mechanical thread to follow up on. Although the examiner recorded it as not excessive, the source should be identified by inspecting underneath the engine for any signs of fresh oil accumulation on the sump, cam cover gasket, or oil filter housing, and it would be prudent to check the current oil level on the dipstick. Given the consistent high-mileage usage, particular attention should be paid to the front suspension during a test drive: listen for knocking or clonking over uneven surfaces and speed humps, which would indicate worn wishbone bushes, anti-roll bar drop links, or top mounts. Steering should feel precise without excess play or vibration, and the front tyres should be examined closely for uneven inner or outer edge wear, which on this record has previously been the most consistent advisory. The braking system should be evaluated with the vehicle warm, as the rear brake pads were noted as wearing thin in 2021 and higher-mileage use can accelerate pad and disc wear disproportionately. During a test drive, the pedal should feel firm and progressive without excessive travel or judder under hard application, and the vehicle should pull up in a straight line without steering deviation. Given the mileage, it is also sensible to inspect the exhaust system visually for any corrosion at the mounting points and joints, and to check for any blue smoke from the exhaust on start-up or under load which could indicate valve stem seal wear. The Mazda 3 platform is mechanically robust, but with nearly 100,000 miles covered, a full inspection of the timing chain area, coolant, and transmission fluid condition would be a sensible precaution alongside the documented MOT findings.